Mohawk Dave
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updated cheat sheet for CUCV
I am making this for myself (and you guys) to carry in my OH9. It's not perfect, but I hope it helps. (I'd say copy and paste from here below) and if you make changes/additions, repost please. Thanks.
This Infornation was obtained from the SteelSoldiers Website
BELTS:
All W/O AC
· Driver side alt- Gates# 7575; Dayco# 15580
· Passenger side alt- Gates# 7483; Dayco# 15490, Goodyear "Gatorback" - 15485
· Power Steering- Gates# 7448; Dayco#15455
AIR CLEANER:
· Any standard filter designated for use in a K5/K30 will work. FRAM# CA3492; NAPA# FIL2096.
HOSES:
NAPA - Upper: NBH7995 Lower:NBH7996
ALTERNATOR:
DRIVERS Side Alternator #7157
Off the shelf replacement alternator for drivers side ONLY.
1975 Caddy Commercial Alternator
100 amps
Ultima - Alternator
Part Number: 01-0136
Our resident CUCV wiring expert, Warthog, assembled my M1009 out of 3 or 4 donors. The wires were all cut off for the alternators and the alternators were not on the truck. One of the reasons I got the truck was that he had new or rebuilt ones on it. I get it home and realize ALT 2 isn't charging.
Now, having read about 20 post a day for the past 5 years about CUCV alternators. I "knew" if the red ALT 2 light wasn't coming on before engine start, the bulb must be burned up which causes the alternator to not work. Mine wasn't coming on, ever, so that must be the problem. I got the truck with no dash or cover on it. I of course didn't figure out the alternator wasn't working until I installed all that stuff.
I called up Joe. He told me to do what I would have done with any other vehicle besides a CUCV. Check voltage at the alternator with the key off and with the key on.
Each alternator is a 12 Volt unit. The big red wire that is bolted on has 12 volts from the battery. The little white plug has 2 wires on it. The thicker is the voltage out of the alternator back to the battery. The smaller wire is the exciter wire.
With the engine off, the big red wire should have battery voltage, so should the bigger wire on the plug and with the plug off, key off, the exciter wire should have nothing.
Turn the key on and the plug off, the exciter wire will have battery voltage along with the other 2.
The above should be your first check of a suspected bad alternator. This tells you if the problem is in the alternator or in the truck. After making sure all wires are hooked up and not grounding out somewhere that is.
My truck side was working properly. I had a problem in the alternator. I called Joe up and asked about the red ALT 2 light. I "knew" it had to be part of the problem because I had read about it here on SS for so long. He kept telling me to ignore the red light. I kept telling him I couldn't, even though it didn't make sense. He told me to look up the -30 procedures for testing the alternator inards and to replace what is bad.
I pulled the alternator off, looked up stuff in the -34 and was lost. They wanted me to build a variable voltage machine just to check out the voltage regulator. I don't have a variable voltage source, so I just threw in a known good regulator and put it back on the truck. I didn't turn the page in the manual to check out all the other components. I took care of the first thing listed in the manual.
The alternator didn't work and the silly ALT 2 light still wasn't coming on. I just knew that ALT 2 light was part of the problem in some way. I still drove the truck though.
Maybe I should cover how you can drive a truck around with a bad alternator and it not be a problem. CUCV's are 12 volt Chevy trucks at heart. The wire for the engine to run, the lights, the blinkers and all that are all 12 volt. The drivers side alternator, ALT1, runs that part of the truck along with the front battery. As long as ALT 1 is good, the truck will drive until you run out of fuel.
The passenger side alternator, ALT 2, only has to charge the rear battery up after the truck has been started. The starter is the only part of the truck that uses the rear battery. I had probably 30 starts on the truck without the battery getting charged. The volt meter was at the top of the yellow zone and the starter turned over at the same speed every time. That was 2 weeks of in town driving without ALT 2.
Since I didn't have the variable voltage thingy machine to test out the alternator, I broke down and paid $44.50 for a complete 27si rebuild kit. All new everything inside the alternator. I put it on and turned on the key. The ALT 2 light lit up. I fired up the engine and the voltage gauge was in the green for the first time since I bought the truck. A volt meter at each battery showed 14.4 and 28.8 across both. It was working.
But, what was wrong? I still had a suspicion that I had hit the dash or something making the light come on and therefore the entire system work. Even though Joe and my test showed the trouble was in the alternator.
I put all the parts I pulled off in a bag and went looking on the Delco Remy site for their version of a test. I posted a thread about the manuals there. They word the test different and I actually turned the page. The Diode Trio and the rectifier bridge can both be tested with a simple Ohm meter. I put new of each in the alternator.
I got out an Ohm meter and tested the Diode Trio I had removed from the alternator. Very simple instructions. Put one lead on the long leg and the other lead on any of the 3 shorter legs. Look at what you get and then switch the leads. One way should be high and the other low. If they are the same, the Diode Trio is bad. My just removed Diode Trio had the same value on all 3 legs with the leads reversed. Bad Diode Trio.
The test for the rectifier bridge is the exact same thing on it. Mine was good.
If you have read this far, you get the summary.
If you are not getting voltage out of an alternator, no light before start up or during running, the exciter wire is exciting and all the other wires are correct. Then I would suggest you spend the $4.00 or so for a new Diode Trio for a 27-si alternator, put it in and go find something else to work on. Or at least read all the pages about testing the alternator parts, test them and then figure out what is bad.
I would look for loose or grounding wires if you have an intermittant fault. The Diode Trio is a solid state component and it pretty much a good or bad. Not a sometimes.
Does your volt meter move up or down with the light showing up or not?
I ask because the si alternators just need the exciter wire to work at start up. Which means as long as they get "turned on", and the engine stays running. They will continue to charge until you turn off the engine. Yours are working, so something somewhere on the truck side is probably either shorting out or not staying connected.
Do the test with the plug on the back of the alternator checking voltage key on and key off. That will tell you to look at the truck wiring or the insides of the alternator. I suspect you will have a loose wire somewhere in the truck harness.
1.Bad belts
2. Misaligned/damaged/dirty pulleys
3. Bad batteries
Bad batteries was my first thought as well. What kind of voltage do they have with the engine off? Check that, then start it and see how far they drop while starting. The 1/2-1 second it takes to start a 6.2 should not drop them down much below 12.0 volts. Anything below 11.0 volts while cranking means you have a battery that can't handle any load.
With the pulleys, look and see if they are shiny all the way down inside the groove. The pulleys are just stamped steel pressed together. As they get old, they sometimes flatten out and the sides of the V on the belts don't make contact anymore. The skinny bottom of the belt is what is turning the alternator. Not near as much surface area, you will get slippage and a belt that stretches and wears out fast.
STARTER:
starter bracket PN GM 22502557
I have ordered from www.gmpartsdirect.com before. Shipping is a little high.
The gear reduction bracket is 23502557 - $15.28 list
The direct drive bracket is 14028931 - $3.32 list
The Starter bolts - 15544950 - $2.80 ea (must buy a box of 5)
The bolt for the braket to block - 14060613 which is a M8 x 1.25 x 20
Gear reduction on the left, direct drive on the right
The part number for the new style gear reduction bracket is 23502557.
It has been listed in 12 differnt treads. Here are a few.
Starter bracket by Gm Discontinued once stock depleted
Broken starter both problem
where can i get a m1009 starter in or near dallas tx.
Starter Support Bracket
The Diode/Rectifier that is used in the Starter Relay circuit and the Gen2 circuit,
is GM Part Number 12006377. Since GM doesn't stock it anymore, Keith_J found a Radio Shack part that works. #276-1144
I would rate this as the third most common problem, but probably the most expensive one if you don't know what to do when it happens.
CUCVs have an extra starter relay under the dash. It is known to either rust and not work making the truck not start or to stick in the on position letting the starter run until the wiring harness or the starter itself burns up and is permanently damaged. You should read the two links below and the links mentioned in them before you even put batteries in the truck. This is probably the most important thing to know and to think about so you will know what to do should it happen to you.
The relay is mounted to the plate that the big plug is mounted to under the edge of the dash next to the 4WD lever. It is the bigger silver relay next to two black relays. Its purpose is to switch the 12v single from the ignition switch to 24v to trigger the 24volt starter. It has four wires plugged into it, The red wire is 24 volt feed. Solid purple goes to the starter. Black is ground. Purple with white stripe is the ignition feed. You can unplug these and jump the red to the purple and start the truck in an emergency. There is a post further down with the part numbers.
GLOW PLUGS:
NAPA - ST85
Or
Ford Powerstroke relay
NAPA - ECHGPR110
Good discussion about the differences between the GPRs
http://www.steelsoldiers.com/index.p...ic&t=21485
The main problems with CUCVs are charging issues and glow plug issues. The original glow plug relay was defective and should have been replaced before the truck left the service. If you have one that looks like the one in last two pictures, you should replace it. Most come out of the service with one like in the third picture. Some of the dealers here have had them in the past. The first picture shows one I got at NAPA. I used ECH GPR109 for $28.49. It looks just like the ECH GPR110 but it is $85.49.
The ST85 looks like what the military went to and is $54.49 at NAPA online or 45.20 at the local store. It also shows one way to bypass the voltage dropping resister. Here is a link to some pictures I took when I replaced my last relay with a ST-85. The old one is what came with the truck from the military.
http://1plant4u.smugmug.com/gallery/...94046840_RAMog
Glowplug relay comparsion - Michael's Photos
The 109 and 110 relays will bolt up with the same holes as the original relay. They don't come with nuts on the posts and they aren't the same size as the original so you will need to get some while you are at the store.
The bid red wire goes on one big post and the two big orange go on the other.
The small blue is on the top small post and the small pink is on the bottom.
I don't think it makes any difference if you get them backwards since the two small wire energize an electromagnet which closes a connection to connect the two big wires. The above pictures was from a truck as it was released from the military.
In the pictures titled NAPA relay, I have run a large white wire to the 12 volt buss to bypass the voltage step-down resistor.
Do not buy AC13G glow plugs. They are obsolete.
The correct direct replacement plug for the cucv is Wellman 070
I prefer AC60G which is what GM recommends for all civilian 6.2 and 6.5 engines
One of the threads above references the NAPA GPR109 glow plug relay. This part is meant for pre-Powerstroke Ford diesels. It is $25 or so while the GPR110 which is very similar costs around $85. We're not sure what the difference is between the two but even the local NAPA couldn't tell me other than to say "$60 more". I used the 109 and so far, so good.
There are two small issues with using the NAPA Ford GPR109 relay, both of which are perfectly fixable.
1. The brackets on the stock relay are of a "north and south" orientation with one on the top and one on the bottom. The 109 has them in a sort of "north and west" orientation. All I did was put the north bracket in the stock hole and then drill a new hole below the stock lower hole to mount the west bracket with. I just couldn't turn it enough to use the stock lower hole without hitting the brake system stuff there to the right of it. Some people have reported they were able to get theirs to line up with the stock holes without trouble but I was unable to do that with mine. Might just be me.
2. The 109's larger studs use different threads than the stock relay's larger studs do. You will have to go out and find new nuts because of this. Minor but it is something to take care of before you're kneeling on the radiator shroud, stretched across the engine cussing.
The two smaller stock studs use the same thread as the 109's smaller studs so their nuts can be reused on the 109.
Note that this is for the original style relay these trucks came with from the factory. I do not know if the updated relay the military used was different.
The wiring diagram for the CUCV glow plug system are incorrect. If you are replacing a missing Glow Plug Relay, the small orange wire goes to the glow plug side of the relay, not the resistor side as shown on the wiring diagram. If it is on the resistor side, the controller will light up the wait light, but will not activate the relay.
LIGHTS/BLACKOUT LIGHTS:
· The right toggle switch moves power to the service lights, horn, dash, etc. or to the blackout lights. Pull it out and flip it up or down.
· The left switch turns on the blackout drive light. Flip it up or down; it will return to center position.
BATTERIES:
· Group 31 or 6TLs
OIL:
· Oil is 15W40 for diesel. Rotella is available in gallon jugs and quarts at just about any convenience store or truck stop. Engine capacity is 7 quarts.
· Oil filter is FRAM# PH13; NAPA# FIL1092; ACDELCO# PF1218CL; K&N# HP-3002
· Oil and filter change recommended every 3 months/3,000 miles
TRANSMISSION:
(TH400, 3-Speed)
· Transmission fluid was indicated as Dexron II. This has been replaced with Dexron III.
· Transmission filter is NAPA# ATP14558 (or 19701 w/gasket); FRAM# FT1020A (w/gasket)
· Capacity is 4 quarts. But this may vary. Fill as needed to reach level.
· Drain/Fill and replace filter every 2 years. Do more frequently if regularly using off-road or for towing
Transfer Case (205 & 20
· Fluid is Dexron III
· Capacity is 5 quarts.
· Level should be approx. 1/4” below edge of filler plug hole
· Drain and fill every 2 years/24,000 miles, or annually if under heavy use
Front/Rear Differential
· Valvoline 80w90 is preferred
· Front capacity is 4.5 pints.
· Rear capacity is 5.4 pints.
FUEL INJECTION:
Fuel filter is NAPA# FIL3136; FRAM#P3940A
The IP is a Stanadyne Roosa Master DB2
If you decide to do a spin-on fuel filer conversion, you can use a hand operated vacuum pump (the same kind for bleeding brakes) to draw fuel from the tank and through the new element. Just hook the hand pump to the filter's output fitting to the IP and pump it a couple dozen times until you get a clear stream of fuel, then reattach the IP/filter line. It only takes a minute and gets rid of all of the trapped air.
If you would like to add an electric fuel pump to make fuel filter changes, water draining, priming after repairs, etc... easier, then you can use a 12v electric pump from a late 80's 6.2L civi truck. I wired it with an inline fuse to an ign. on circuit on the fuse block and used GM weather-pack connectors to make it look factory. I used it like that for 8 years without a problem. Just make sure to use an inline filter before the pump to catch any trash. Change it when you change your primary filter can. Also mount the pump on the frame close to the fuel tank so the fuel with keep the pump cool and it will also be less likely to suck air through a pinhole in the line. It's always easier to find a hole in your fuel line with a drip.
prob want to put this in the sticky in the hmmwv and Cucv threads but you can get them from about any parts store. I called Napa, Autozone, Advance, and orielly. they could all get it.
Dorman 904-101
it was $9.52
This is the kit that will get you all the little rubber flex lines that go on the injectors and the clamps that hold them on. Does not come with the caps for #7 and #8
when replacing the fuel lift pump on the cucv the little mettle rod that actuates the pump must be inserted fully into its little hole to get it to stay up in place put a little wheel bearign grease on the end that slides in
KEYS:
Key "B" blank 73Y2 cut
WATER/THERMOSTAT:
The Hockey Puck thermostat for the CUCVS are available at NAPA, Autozone and Oreilly's (and others of course).
NAPA - 381190
Autozone and Oreilly's - Murray 42995
Thermostat housing gasket - Felpro 35271, Murray 2140
Thermostat Housing (Water Outlet) - Murray 84987
ELECTRICAL:
If you are troubleshooting the CUCV electrical system, the wiring diagrams are in the Appendix of the Tech Manuals. Appendix F of TM 9-2320-289-20 and Appendix E of the TM 9-2320-289-34.
Also if you need instructions or a refresher on how to read the diagrams, read the first few pages of the TroubleShooting section of the above manuals.
They cover how to read the diagrams, wire labeling, wire sizes, colors, etc.....
I have cut and pasted each of the diagrams, and saved them on my hard drive. When I am troubleshooting a system, I open the diagram up in MS Paint and color the wires to make the diagram easier to read.
CDR-PCV VALVE:
GM - 25042462
NAPA CRB229143 is the incorrect valve...
This is a good discussion about the replacement valve.
http://www.steelsoldiers.com/index.p...ic&t=21492
CDR valves are important but unfortunately not supported in the aftermarket and GM wants an arm, a leg, and something else (or two) for them.
These should be replaced every 50k according to GM (correct me if I'm wrong) but the diesel gurus seem to agree that much more frequent intervals are better. However it seems like they aren't common in the aftermarket as a replacement part. Pretty much the GM/AC Delco route is the only one any of us could find in my CDR thread.
The correct GM part number for the military spec'd part is 25042462 with AC Delco calling the same part the CV871. The part listed for a 1986 Chevy K30 6.2L civilian truck is a 25042248 in the GM parts book and a CV870 according to AC Delco. GM and EVERYONE else list the military spec part as obsolete and it's a dead end. The civilian part could not be located at NAPA, Advanced Auto (Kragen/Schucks/Shumers), Auto Zone, CarQuest, and two local places here in Traverse City, MI. The only locations I personally could find them were my local GM dealers at $71 each and www.Rock-Auto.com for about $41 delivered.
I have a feeling these are becoming a rare part as the box I received is definitely old having the older AC label on it and the date code on the box being from 1997. Others have alluded to getting the part from different suppliers but I haven't tracked this down. I'd definitely consider mine NOS.
The civilian part bolts right to the CUCV's mount and the hoses hook right up to it. Mine had a slightly different angle on the pipe that curves out and away towards the front of the truck but it might just be a manufacturing deviation and didn't pose any sort of problem.
HEATER:
The heater blower motor from NAPA is the heavy duty one. The blower motor part # from NAPA is 655-1076
POWER STEERING:
Power Steering Pump bracket part number is
GM# 14033879
VIN #:
Does your vin number contain HD in it?
Like this, 1GCHD34J0HF311237 (should have front locker)
or is it like this, 1GCGD34J2FF439536 (does not usually have front locker) There's only 1 exception to the 4th digit being a "H" and that applies to the M1010 which has the "H" because of weight but does NOT have the "Trac-Lok" front D60. All others with the "H" came with the "Trac-Lok".
TROUBLESHOOTING:
In order to properly troubleshoot a Stanadyne DB2 application, you must insure the following conditions are met:
1) Voltage – You must have the correct voltage to the shut off solenoid and to the cold start advance solenoid.
2) You should also have the pump properly timed. Please refer to the manufacturers timing information for complete timing instructions in the tech manuals.
3) You should also have a solid stream of return before the pump can achieve starting capacity. Return can be measured here. You can also attach a clear line to check the return for air bubbles here.
4) You should also have a minimum of 150-200 cranking RPMs. If your batteries are weak and you are not attaining the minimum cranking, your vehicle will not start.
INJECTION PUMP BLEEDING
Once you have satisfied these four requirements, the injection pump should be bleed. This is best done by attaching and properly tightening the lines at the head of the injection pump, and loosely attaching them at the injectors. As you are turning the vehicle over, you will begin to get a fuel foam, a mixture of air and fuel, coming out at the line connection, at that time go ahead and lock down the line nut to the injector. Repeat procedure until all lines are bleed completely.
If after doing this procedure the vehicle does not start, please do the following:
1) Attach a clear line to the return side of the injection pump and inspect for air bubbles. If you have air getting into the system, correct the problem before proceeding.
2) Attach a hose directly from the injection pump to an alternate source of fuel. You will need approximately 2-5 gallons for this test. You will need to bypass the entire fuel system, including the lift pump, for this test to be done properly. The injection pump has an internal supply pump that will pull fuel from the source.
GENERAL:
CUCVs use metric bolts so you will need metric tools to work on them.
You can find all the GM part numbers you will ever need in the Technical Manual Parts listings.
TM 9-2320-289-20p and TM 9-2320-289-34p
if your expieriencing vibrations at low speeds try rotating your rear driveshaft 180* on the pinion.
Unless the engine is in rough mechanical shape or on it's last legs, it should see a redline of 3600rpm... but after about 2400-2500rpm, you're losing power & wasting fuel. IIRC, max torque occurs in 1800-2200rpm range on a 6.2 -
I am making this for myself (and you guys) to carry in my OH9. It's not perfect, but I hope it helps. (I'd say copy and paste from here below) and if you make changes/additions, repost please. Thanks.
This Infornation was obtained from the SteelSoldiers Website
BELTS:
All W/O AC
· Driver side alt- Gates# 7575; Dayco# 15580
· Passenger side alt- Gates# 7483; Dayco# 15490, Goodyear "Gatorback" - 15485
· Power Steering- Gates# 7448; Dayco#15455
AIR CLEANER:
· Any standard filter designated for use in a K5/K30 will work. FRAM# CA3492; NAPA# FIL2096.
HOSES:
NAPA - Upper: NBH7995 Lower:NBH7996
ALTERNATOR:
DRIVERS Side Alternator #7157
Off the shelf replacement alternator for drivers side ONLY.
1975 Caddy Commercial Alternator
100 amps
Ultima - Alternator
Part Number: 01-0136
Our resident CUCV wiring expert, Warthog, assembled my M1009 out of 3 or 4 donors. The wires were all cut off for the alternators and the alternators were not on the truck. One of the reasons I got the truck was that he had new or rebuilt ones on it. I get it home and realize ALT 2 isn't charging.
Now, having read about 20 post a day for the past 5 years about CUCV alternators. I "knew" if the red ALT 2 light wasn't coming on before engine start, the bulb must be burned up which causes the alternator to not work. Mine wasn't coming on, ever, so that must be the problem. I got the truck with no dash or cover on it. I of course didn't figure out the alternator wasn't working until I installed all that stuff.
I called up Joe. He told me to do what I would have done with any other vehicle besides a CUCV. Check voltage at the alternator with the key off and with the key on.
Each alternator is a 12 Volt unit. The big red wire that is bolted on has 12 volts from the battery. The little white plug has 2 wires on it. The thicker is the voltage out of the alternator back to the battery. The smaller wire is the exciter wire.
With the engine off, the big red wire should have battery voltage, so should the bigger wire on the plug and with the plug off, key off, the exciter wire should have nothing.
Turn the key on and the plug off, the exciter wire will have battery voltage along with the other 2.
The above should be your first check of a suspected bad alternator. This tells you if the problem is in the alternator or in the truck. After making sure all wires are hooked up and not grounding out somewhere that is.
My truck side was working properly. I had a problem in the alternator. I called Joe up and asked about the red ALT 2 light. I "knew" it had to be part of the problem because I had read about it here on SS for so long. He kept telling me to ignore the red light. I kept telling him I couldn't, even though it didn't make sense. He told me to look up the -30 procedures for testing the alternator inards and to replace what is bad.
I pulled the alternator off, looked up stuff in the -34 and was lost. They wanted me to build a variable voltage machine just to check out the voltage regulator. I don't have a variable voltage source, so I just threw in a known good regulator and put it back on the truck. I didn't turn the page in the manual to check out all the other components. I took care of the first thing listed in the manual.
The alternator didn't work and the silly ALT 2 light still wasn't coming on. I just knew that ALT 2 light was part of the problem in some way. I still drove the truck though.
Maybe I should cover how you can drive a truck around with a bad alternator and it not be a problem. CUCV's are 12 volt Chevy trucks at heart. The wire for the engine to run, the lights, the blinkers and all that are all 12 volt. The drivers side alternator, ALT1, runs that part of the truck along with the front battery. As long as ALT 1 is good, the truck will drive until you run out of fuel.
The passenger side alternator, ALT 2, only has to charge the rear battery up after the truck has been started. The starter is the only part of the truck that uses the rear battery. I had probably 30 starts on the truck without the battery getting charged. The volt meter was at the top of the yellow zone and the starter turned over at the same speed every time. That was 2 weeks of in town driving without ALT 2.
Since I didn't have the variable voltage thingy machine to test out the alternator, I broke down and paid $44.50 for a complete 27si rebuild kit. All new everything inside the alternator. I put it on and turned on the key. The ALT 2 light lit up. I fired up the engine and the voltage gauge was in the green for the first time since I bought the truck. A volt meter at each battery showed 14.4 and 28.8 across both. It was working.
But, what was wrong? I still had a suspicion that I had hit the dash or something making the light come on and therefore the entire system work. Even though Joe and my test showed the trouble was in the alternator.
I put all the parts I pulled off in a bag and went looking on the Delco Remy site for their version of a test. I posted a thread about the manuals there. They word the test different and I actually turned the page. The Diode Trio and the rectifier bridge can both be tested with a simple Ohm meter. I put new of each in the alternator.
I got out an Ohm meter and tested the Diode Trio I had removed from the alternator. Very simple instructions. Put one lead on the long leg and the other lead on any of the 3 shorter legs. Look at what you get and then switch the leads. One way should be high and the other low. If they are the same, the Diode Trio is bad. My just removed Diode Trio had the same value on all 3 legs with the leads reversed. Bad Diode Trio.
The test for the rectifier bridge is the exact same thing on it. Mine was good.
If you have read this far, you get the summary.
If you are not getting voltage out of an alternator, no light before start up or during running, the exciter wire is exciting and all the other wires are correct. Then I would suggest you spend the $4.00 or so for a new Diode Trio for a 27-si alternator, put it in and go find something else to work on. Or at least read all the pages about testing the alternator parts, test them and then figure out what is bad.
I would look for loose or grounding wires if you have an intermittant fault. The Diode Trio is a solid state component and it pretty much a good or bad. Not a sometimes.
Does your volt meter move up or down with the light showing up or not?
I ask because the si alternators just need the exciter wire to work at start up. Which means as long as they get "turned on", and the engine stays running. They will continue to charge until you turn off the engine. Yours are working, so something somewhere on the truck side is probably either shorting out or not staying connected.
Do the test with the plug on the back of the alternator checking voltage key on and key off. That will tell you to look at the truck wiring or the insides of the alternator. I suspect you will have a loose wire somewhere in the truck harness.
1.Bad belts
2. Misaligned/damaged/dirty pulleys
3. Bad batteries
Bad batteries was my first thought as well. What kind of voltage do they have with the engine off? Check that, then start it and see how far they drop while starting. The 1/2-1 second it takes to start a 6.2 should not drop them down much below 12.0 volts. Anything below 11.0 volts while cranking means you have a battery that can't handle any load.
With the pulleys, look and see if they are shiny all the way down inside the groove. The pulleys are just stamped steel pressed together. As they get old, they sometimes flatten out and the sides of the V on the belts don't make contact anymore. The skinny bottom of the belt is what is turning the alternator. Not near as much surface area, you will get slippage and a belt that stretches and wears out fast.
STARTER:
starter bracket PN GM 22502557
I have ordered from www.gmpartsdirect.com before. Shipping is a little high.
The gear reduction bracket is 23502557 - $15.28 list
The direct drive bracket is 14028931 - $3.32 list
The Starter bolts - 15544950 - $2.80 ea (must buy a box of 5)
The bolt for the braket to block - 14060613 which is a M8 x 1.25 x 20
Gear reduction on the left, direct drive on the right
The part number for the new style gear reduction bracket is 23502557.
It has been listed in 12 differnt treads. Here are a few.
Starter bracket by Gm Discontinued once stock depleted
Broken starter both problem
where can i get a m1009 starter in or near dallas tx.
Starter Support Bracket
The Diode/Rectifier that is used in the Starter Relay circuit and the Gen2 circuit,
is GM Part Number 12006377. Since GM doesn't stock it anymore, Keith_J found a Radio Shack part that works. #276-1144
I would rate this as the third most common problem, but probably the most expensive one if you don't know what to do when it happens.
CUCVs have an extra starter relay under the dash. It is known to either rust and not work making the truck not start or to stick in the on position letting the starter run until the wiring harness or the starter itself burns up and is permanently damaged. You should read the two links below and the links mentioned in them before you even put batteries in the truck. This is probably the most important thing to know and to think about so you will know what to do should it happen to you.
The relay is mounted to the plate that the big plug is mounted to under the edge of the dash next to the 4WD lever. It is the bigger silver relay next to two black relays. Its purpose is to switch the 12v single from the ignition switch to 24v to trigger the 24volt starter. It has four wires plugged into it, The red wire is 24 volt feed. Solid purple goes to the starter. Black is ground. Purple with white stripe is the ignition feed. You can unplug these and jump the red to the purple and start the truck in an emergency. There is a post further down with the part numbers.
GLOW PLUGS:
NAPA - ST85
Or
Ford Powerstroke relay
NAPA - ECHGPR110
Good discussion about the differences between the GPRs
http://www.steelsoldiers.com/index.p...ic&t=21485
The main problems with CUCVs are charging issues and glow plug issues. The original glow plug relay was defective and should have been replaced before the truck left the service. If you have one that looks like the one in last two pictures, you should replace it. Most come out of the service with one like in the third picture. Some of the dealers here have had them in the past. The first picture shows one I got at NAPA. I used ECH GPR109 for $28.49. It looks just like the ECH GPR110 but it is $85.49.
The ST85 looks like what the military went to and is $54.49 at NAPA online or 45.20 at the local store. It also shows one way to bypass the voltage dropping resister. Here is a link to some pictures I took when I replaced my last relay with a ST-85. The old one is what came with the truck from the military.
http://1plant4u.smugmug.com/gallery/...94046840_RAMog
Glowplug relay comparsion - Michael's Photos
The 109 and 110 relays will bolt up with the same holes as the original relay. They don't come with nuts on the posts and they aren't the same size as the original so you will need to get some while you are at the store.
The bid red wire goes on one big post and the two big orange go on the other.
The small blue is on the top small post and the small pink is on the bottom.
I don't think it makes any difference if you get them backwards since the two small wire energize an electromagnet which closes a connection to connect the two big wires. The above pictures was from a truck as it was released from the military.
In the pictures titled NAPA relay, I have run a large white wire to the 12 volt buss to bypass the voltage step-down resistor.
Do not buy AC13G glow plugs. They are obsolete.
The correct direct replacement plug for the cucv is Wellman 070
I prefer AC60G which is what GM recommends for all civilian 6.2 and 6.5 engines
One of the threads above references the NAPA GPR109 glow plug relay. This part is meant for pre-Powerstroke Ford diesels. It is $25 or so while the GPR110 which is very similar costs around $85. We're not sure what the difference is between the two but even the local NAPA couldn't tell me other than to say "$60 more". I used the 109 and so far, so good.
There are two small issues with using the NAPA Ford GPR109 relay, both of which are perfectly fixable.
1. The brackets on the stock relay are of a "north and south" orientation with one on the top and one on the bottom. The 109 has them in a sort of "north and west" orientation. All I did was put the north bracket in the stock hole and then drill a new hole below the stock lower hole to mount the west bracket with. I just couldn't turn it enough to use the stock lower hole without hitting the brake system stuff there to the right of it. Some people have reported they were able to get theirs to line up with the stock holes without trouble but I was unable to do that with mine. Might just be me.
2. The 109's larger studs use different threads than the stock relay's larger studs do. You will have to go out and find new nuts because of this. Minor but it is something to take care of before you're kneeling on the radiator shroud, stretched across the engine cussing.
The two smaller stock studs use the same thread as the 109's smaller studs so their nuts can be reused on the 109.
Note that this is for the original style relay these trucks came with from the factory. I do not know if the updated relay the military used was different.
The wiring diagram for the CUCV glow plug system are incorrect. If you are replacing a missing Glow Plug Relay, the small orange wire goes to the glow plug side of the relay, not the resistor side as shown on the wiring diagram. If it is on the resistor side, the controller will light up the wait light, but will not activate the relay.
LIGHTS/BLACKOUT LIGHTS:
· The right toggle switch moves power to the service lights, horn, dash, etc. or to the blackout lights. Pull it out and flip it up or down.
· The left switch turns on the blackout drive light. Flip it up or down; it will return to center position.
BATTERIES:
· Group 31 or 6TLs
OIL:
· Oil is 15W40 for diesel. Rotella is available in gallon jugs and quarts at just about any convenience store or truck stop. Engine capacity is 7 quarts.
· Oil filter is FRAM# PH13; NAPA# FIL1092; ACDELCO# PF1218CL; K&N# HP-3002
· Oil and filter change recommended every 3 months/3,000 miles
TRANSMISSION:
(TH400, 3-Speed)
· Transmission fluid was indicated as Dexron II. This has been replaced with Dexron III.
· Transmission filter is NAPA# ATP14558 (or 19701 w/gasket); FRAM# FT1020A (w/gasket)
· Capacity is 4 quarts. But this may vary. Fill as needed to reach level.
· Drain/Fill and replace filter every 2 years. Do more frequently if regularly using off-road or for towing
Transfer Case (205 & 20
· Fluid is Dexron III
· Capacity is 5 quarts.
· Level should be approx. 1/4” below edge of filler plug hole
· Drain and fill every 2 years/24,000 miles, or annually if under heavy use
Front/Rear Differential
· Valvoline 80w90 is preferred
· Front capacity is 4.5 pints.
· Rear capacity is 5.4 pints.
FUEL INJECTION:
Fuel filter is NAPA# FIL3136; FRAM#P3940A
The IP is a Stanadyne Roosa Master DB2
If you decide to do a spin-on fuel filer conversion, you can use a hand operated vacuum pump (the same kind for bleeding brakes) to draw fuel from the tank and through the new element. Just hook the hand pump to the filter's output fitting to the IP and pump it a couple dozen times until you get a clear stream of fuel, then reattach the IP/filter line. It only takes a minute and gets rid of all of the trapped air.
If you would like to add an electric fuel pump to make fuel filter changes, water draining, priming after repairs, etc... easier, then you can use a 12v electric pump from a late 80's 6.2L civi truck. I wired it with an inline fuse to an ign. on circuit on the fuse block and used GM weather-pack connectors to make it look factory. I used it like that for 8 years without a problem. Just make sure to use an inline filter before the pump to catch any trash. Change it when you change your primary filter can. Also mount the pump on the frame close to the fuel tank so the fuel with keep the pump cool and it will also be less likely to suck air through a pinhole in the line. It's always easier to find a hole in your fuel line with a drip.
prob want to put this in the sticky in the hmmwv and Cucv threads but you can get them from about any parts store. I called Napa, Autozone, Advance, and orielly. they could all get it.
Dorman 904-101
it was $9.52
This is the kit that will get you all the little rubber flex lines that go on the injectors and the clamps that hold them on. Does not come with the caps for #7 and #8
when replacing the fuel lift pump on the cucv the little mettle rod that actuates the pump must be inserted fully into its little hole to get it to stay up in place put a little wheel bearign grease on the end that slides in
KEYS:
Key "B" blank 73Y2 cut
WATER/THERMOSTAT:
The Hockey Puck thermostat for the CUCVS are available at NAPA, Autozone and Oreilly's (and others of course).
NAPA - 381190
Autozone and Oreilly's - Murray 42995
Thermostat housing gasket - Felpro 35271, Murray 2140
Thermostat Housing (Water Outlet) - Murray 84987
ELECTRICAL:
If you are troubleshooting the CUCV electrical system, the wiring diagrams are in the Appendix of the Tech Manuals. Appendix F of TM 9-2320-289-20 and Appendix E of the TM 9-2320-289-34.
Also if you need instructions or a refresher on how to read the diagrams, read the first few pages of the TroubleShooting section of the above manuals.
They cover how to read the diagrams, wire labeling, wire sizes, colors, etc.....
I have cut and pasted each of the diagrams, and saved them on my hard drive. When I am troubleshooting a system, I open the diagram up in MS Paint and color the wires to make the diagram easier to read.
CDR-PCV VALVE:
GM - 25042462
NAPA CRB229143 is the incorrect valve...
This is a good discussion about the replacement valve.
http://www.steelsoldiers.com/index.p...ic&t=21492
CDR valves are important but unfortunately not supported in the aftermarket and GM wants an arm, a leg, and something else (or two) for them.
These should be replaced every 50k according to GM (correct me if I'm wrong) but the diesel gurus seem to agree that much more frequent intervals are better. However it seems like they aren't common in the aftermarket as a replacement part. Pretty much the GM/AC Delco route is the only one any of us could find in my CDR thread.
The correct GM part number for the military spec'd part is 25042462 with AC Delco calling the same part the CV871. The part listed for a 1986 Chevy K30 6.2L civilian truck is a 25042248 in the GM parts book and a CV870 according to AC Delco. GM and EVERYONE else list the military spec part as obsolete and it's a dead end. The civilian part could not be located at NAPA, Advanced Auto (Kragen/Schucks/Shumers), Auto Zone, CarQuest, and two local places here in Traverse City, MI. The only locations I personally could find them were my local GM dealers at $71 each and www.Rock-Auto.com for about $41 delivered.
I have a feeling these are becoming a rare part as the box I received is definitely old having the older AC label on it and the date code on the box being from 1997. Others have alluded to getting the part from different suppliers but I haven't tracked this down. I'd definitely consider mine NOS.
The civilian part bolts right to the CUCV's mount and the hoses hook right up to it. Mine had a slightly different angle on the pipe that curves out and away towards the front of the truck but it might just be a manufacturing deviation and didn't pose any sort of problem.
HEATER:
The heater blower motor from NAPA is the heavy duty one. The blower motor part # from NAPA is 655-1076
POWER STEERING:
Power Steering Pump bracket part number is
GM# 14033879
VIN #:
Does your vin number contain HD in it?
Like this, 1GCHD34J0HF311237 (should have front locker)
or is it like this, 1GCGD34J2FF439536 (does not usually have front locker) There's only 1 exception to the 4th digit being a "H" and that applies to the M1010 which has the "H" because of weight but does NOT have the "Trac-Lok" front D60. All others with the "H" came with the "Trac-Lok".
TROUBLESHOOTING:
In order to properly troubleshoot a Stanadyne DB2 application, you must insure the following conditions are met:
1) Voltage – You must have the correct voltage to the shut off solenoid and to the cold start advance solenoid.
2) You should also have the pump properly timed. Please refer to the manufacturers timing information for complete timing instructions in the tech manuals.
3) You should also have a solid stream of return before the pump can achieve starting capacity. Return can be measured here. You can also attach a clear line to check the return for air bubbles here.
4) You should also have a minimum of 150-200 cranking RPMs. If your batteries are weak and you are not attaining the minimum cranking, your vehicle will not start.
INJECTION PUMP BLEEDING
Once you have satisfied these four requirements, the injection pump should be bleed. This is best done by attaching and properly tightening the lines at the head of the injection pump, and loosely attaching them at the injectors. As you are turning the vehicle over, you will begin to get a fuel foam, a mixture of air and fuel, coming out at the line connection, at that time go ahead and lock down the line nut to the injector. Repeat procedure until all lines are bleed completely.
If after doing this procedure the vehicle does not start, please do the following:
1) Attach a clear line to the return side of the injection pump and inspect for air bubbles. If you have air getting into the system, correct the problem before proceeding.
2) Attach a hose directly from the injection pump to an alternate source of fuel. You will need approximately 2-5 gallons for this test. You will need to bypass the entire fuel system, including the lift pump, for this test to be done properly. The injection pump has an internal supply pump that will pull fuel from the source.
GENERAL:
CUCVs use metric bolts so you will need metric tools to work on them.
You can find all the GM part numbers you will ever need in the Technical Manual Parts listings.
TM 9-2320-289-20p and TM 9-2320-289-34p
if your expieriencing vibrations at low speeds try rotating your rear driveshaft 180* on the pinion.
Unless the engine is in rough mechanical shape or on it's last legs, it should see a redline of 3600rpm... but after about 2400-2500rpm, you're losing power & wasting fuel. IIRC, max torque occurs in 1800-2200rpm range on a 6.2 -
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