MEP-005 Fuel Injection Pump

[epitts]

If you don't mind me asking, what type and model is the pump?

 

[Isaac-1]

If you do take it apart all the way at least invest in a $25 rebuild kit with all new rubber parts, you can find them on ebay, etc.

 

[Rickety Bones]

the pump is a stanadyne DBMFC-633 1LK,

 

[leedawg]

Here is a rebuilt unit on ebay right now, little bit insane of a price if you ask me.

Stanadyne Generator Fuel Injection Pump DBMFC633-1LK | eBay

 

[timbosama]

I have the same issue: fuel to IP; solenoid works; lever inside was sticky, but is free now; no fuel to injector lines.

What does the solenoid do, anyway? I don't see what the "hook" thing on the end of the solenoid is supposed to engage with inside the pump. All mine seems to be doing is rubbing against the axle that the shut-off lever turns.

Thanks for any help.

 

[M35A2-AZ]

I have had my MEP-005a for a number of mouths now and I finely got around to trying to start it, and it does not start.
Has all the same problems listed in this thread.
I have gotten the fuel to the IP pump.
I will keep you updated and hopefully not ask to many (dumb) questions.

I do have one right now, well two.
1. On the fault lights when I turn the gen. to run I get a oil pressure fault. see that right?
2. The lever on the ip pump should it be move back toward the bell house on the motor?
Thanks!!

 

[timbosama]

On the oil light, I think this is normal for the non-running situation. The low oil pressure light will come on when the start-run-stop switch is in the run position, and the engine is not running: the oil pressure sensor is energized, but there is no oil pressure because the engine isn't running. If the light stays on once the engine is running, and the oil pressure gauge shows no pressure, then you have a problem.

On the pump lever, it is either all the way clockwise, or all the way CCW. see leedawg's posts #31 and 32 on page 4 of this thread. I think he is saying all the way CW.

 

[leedawg]

On the oil light, I think this is normal for the non-running situation. The low oil pressure light will come on when the start-run-stop switch is in the run position, and the engine is not running: the oil pressure sensor is energized, but there is no oil pressure because the engine isn't running. If the light stays on once the engine is running, and the oil pressure gauge shows no pressure, then you have a problem.

On the pump lever, it is either all the way clockwise, or all the way CCW. see leedawg's posts #31 and 32 on page 4 of this thread. I think he is saying all the way CW.

The lever is all the way back toward the bell housing as was mentioned above which would be CCW.

The solenoid is responsible for shutting the fuel off to the injector pump so the motor stops and can be controlled by the electrical system on the set instead of having to go over there and manually pull the shut off valve which is that lever.

The hook engages the fuel valve inside the injection pump. The way it works is its a spring loaded off position so if there is no power to the solenoid then the fuel pump is off and not pumping fuel. When the solenoid is energized it pulls the hook forward allowing the fuel cut off lever to move to the governor preset position and thus allow fuel to flow through the pump. However Alot of these pumps the fuel shut off has been in the off position for so long with old fuel in the pump that this lever inside the pump is seized up and in this position. Seems bout 50 percent will work if your free this lever up and the others require rebuild. Almost all the ones ive seen however the flex ring is deteriorating and putting out what looks like coffee grounds into the internals of the pump which flow around the fuel system. SO a rebuild is not a bad idea.

 

[timbosama]

OK, thank you.

I had the cover off last night, and the hook didn't seem to be hooked into anything. The strong side of the hook just seemed to be lightly pressed against the radiator side of the shut-off lever arm, with the hook side even closer to the radiator and connected to nothing. I'll look again tonight, but did I miss an obvious connection in there?

The cutoff lever was sticky, but I got it freed up, so it moves when the outside lever is moved now.

I tested the solenoid by connecting it directly to the batteries, and it worked, but I didn't hear it click after it was reinstalled. Maybe the leads are backwards?

I checked for and did not find any debris in the pump or check valve when I had the cover off.

 

[M35A2-AZ]

Thanks guys for the help!!! I went to open up the IP and I do not have the right size Trox Tamperpoof driver to remove it.
Off to town on Monday I guess...

I did a little more testing and I have fuel coming out of the return, but none coming out of the lines to the injectors. I put power to the pump and I can hear it click. Will take it apart when I get the trox driver.

 

[leedawg]

OK, thank you.

I had the cover off last night, and the hook didn't seem to be hooked into anything. The strong side of the hook just seemed to be lightly pressed against the radiator side of the shut-off lever arm, with the hook side even closer to the radiator and connected to nothing. I'll look again tonight, but did I miss an obvious connection in there?

The cutoff lever was sticky, but I got it freed up, so it moves when the outside lever is moved now.

I tested the solenoid by connecting it directly to the batteries, and it worked, but I didn't hear it click after it was reinstalled. Maybe the leads are backwards?

I checked for and did not find any debris in the pump or check valve when I had the cover off.

It does not hook onto anything it just pushes that shut off lever into the position you found it when you opened the pump up by a spring loaded device in the solenoid. WHen the solenoid activate it moves that lever thing forward and if the fuel shut off lever is free i follows moving away from the radiator toward the bell housing of the motor.

Wiring does not matter on any electromagnet (which the solenoid is) Power across it is power across it.

Thanks guys for the help!!! I went to open up the IP and I do not have the right size Trox Tamperpoof driver to remove it.
Off to town on Monday I guess...

I did a little more testing and I have fuel coming out of the return, but none coming out of the lines to the injectors. I put power to the pump and I can hear it click. Will take it apart when I get the trox driver.

Most likely your shut off valve is also siezed up from sitting for to long with old fuel in it in the off position. No fuel out of the injector lines means the motor wont run..

Mine both had standard hex drives on the bolts holding my pump together guess they had tamper torx on some of them what a pain... Good luck

Lee

 

[timbosama]

Thank you, Lee.

Before I read your response this evening, I got a better look inside the pump cover and saw the part of the fuel shut-off lever that it pushes against. I also wired the solenoid both ways, and it sure does work either way you hook it up

But it still isn't sending fuel to the injectors, so I reckon I'll have to pull it off and see what else is hung up in there. I'll post if I find anything interesting.

Thanks again.

Tim

 

[M35A2-AZ]

Well I got my Trox tamper-poof bits today fro the top of the IP pump cover. But I did not notice last week that the bolts are 5 point and Trox are 6 point. Have to get more bits now.

 

[M35A2-AZ]

I got the cover off the pump and it looked like old diesel in it.
I cleaned it the best I could, all the parts looked liked they were moving ok but still no fuel to the injectors.

I guess the only thing left is to take it to get rebuilt.

Any ideas?

 

[M35A2-AZ]

I got the Pump pulled, but I could not figure how to get the pump shaft off of the timing/drive pulley.

FYI, I took the pump in and the shop does not need the shaft to rebuild it. They have shafts to use for testing.

 

[leedawg]

I got the Pump pulled, but I could not figure how to get the pump shaft off of the timing/drive pulley.

FYI, I took the pump in and the shop does not need the shaft to rebuild it. They have shafts to use for testing.

Yup that is what I did. However when I got the pump back after it had been rebuilt I was unable to get it in time properly with where the shaft was set in the timing gear hopefully you do not run into this problem otherwise you will have to take the shaft out of the timing gear to set it to the proper spot so the pump is timed right to the flywheel marks.

Here is how I got my shaft out everybody said I could hammer it out did not work for me that thing is really in there its a tapered shaft so its practically cold welded into that timing gear. I basically two pieces of angle iron and drilled two holes in each of them the right distance for the bolt holes of the inspection cover to line up with them. I then put the bolts through the two pieces of angle iron and then that gave me a ledge that I could get the bearing puller arms to catch against. I then used the bearing puller to press the shaft out of the taper. It was super tight then the shaft popped out of the timing gear sounded like a gun shot when it went then I was able to put the pump in the middle position of the holes and line the lines up exactly in the middle when the flywheel was at the right spot through the inspection window.

Here is a link to the thread showing what I did with pictures.

http://www.smokstak.com/forum/showthread.php?t=112788

Lee

 

[M35A2-AZ]

Lee, Thanks for the info. and the link.!!!

 

[M35A2-AZ]

Lee, I got my pump back from repair and it lined OK with the shaft like I left it.
Twenty degrees on the motor and the two lines on the pump all line up.
But the guy at the pump shop said to make sure the two dots, one on the shaft end and one inside the
pump line up. I looked and my dots are 180 degrees out. But if the shaft is not keyed it should not make any
deference, Right???
Thanks!!

 

[leedawg]

Lee, I got my pump back from repair and it lined OK with the shaft like I left it.
Twenty degrees on the motor and the two lines on the pump all line up.
But the guy at the pump shop said to make sure the two dots, one on the shaft end and one inside the
pump line up. I looked and my dots are 180 degrees out. But if the shaft is not keyed it should not make any
deference, Right???
Thanks!!

LOL Yeah I was told the exact same thing. Um so quick question were they lined up when you pulled the pump off? If so Id say you should probably line them up again. I personally dont see why it makes any difference what so ever I mean its just turning the pump. The only thing I can think of is perhaps you could be 180 degrees out of time if the dots are not lined up. Are you sure you are on the compression stroke on Cyl #1? I pulled my valve covers and verified this and then set the shaft into the timing gear so my dots lined up and the lines lined up. However if your stuff is lining up as is id say you should be good to go. Crank her over and fire it up. Its either going to run or its going to run like crap and be very hard to start with fuel pumping up to the injectors. If that is the case you are probably 180 degrees out of time and need to spin the crank around again till the shaft lines up with the dots on the pump. The other thing you could do is just put a really big flat head screw driver in there and spin the pump 180 degrees and the dots should line up but your timing line may not line up then..

Id say crank it over see how she goes as it is since you have it all installed. It will probably run great.. Let us know

Lee

 

[M35A2-AZ]

Lee, Thanks. I did not know about the dots when I took it apart so I do not check.
I have just put the pump on with no line or fuel lines.
If the motor is at 20 degrees and I turn it over again that would be 360 digress right? I'm thinking out loud.
So when the flywheel turn 360 the pump turns 360 right?
If I turn the pump to alien the dots then the two lines on the pump will not lineup.
I think my head is about expode.
thanks!