M35a2 Wont start

[DalekEngineer]

My M35a2 won’t start, it will almost start while cranking but won’t. Yesterday it would be a little hard to start but when it got running it ran good and then it would die out of nowhere and started back up a couple of times and then one time it died it just wouldn’t start so I tried today and it will almost start but won’t. The fuel shut off is working and moves back and forth, there is fuel coming back out of the fuel return from the injectors, so I’m here asking you guys what I should do? At this point I’m not really sure.

 

[gimpyrobb]

When was the last time you put new fuel filters in? Has the truck ever ran? Is the in tank pump running?

 

[Welder1]

I would replace all the filters as Gimp suggested. I also would check the make sure the fuel shutoff is in the 7 o'clock position if not hard starting can result. The in tank pump should give you good flow at the secondary filter bleed port. If all that is good it should start.



Eddie

 

[DalekEngineer]

I bought this deuce about a month and a half ago and at that time I didn’t know what I was doing so I’ve done a lot of research on here, the first time I started it ran away but I was able to kill it quickly. I found out that the fuel shut off can stick so that’s what I tried next, it was so stuck I had to tear it apart ( I didn’t pay attention when I took it apart) so when I put it together it would never start, so I tried all sorts of things I took out the whole IP cleaned it to the best of my ability, Cleaned the HH, made sure the injector lines were clean put it back together and nothing, eventually I realized I put the fuel shut off in wrong. I did replace the second and final filter and brake cleaned out the primary filter, I also replaced the fuel, after I put the fuel shut off back correctly it fired right up it would start on its own just fine, I drove it for a couple days around the house and it kept getting harder to start and eventually nothing, even using ether it will only start on the ether. Today I’ll male sure it has good pressure at the secondary filter. Thank you for the help

 

[Ajax MD]

Based on this description, it sounds like you might have algae in the fuel tank and you keep sucking it into the fuel system.
You cleaned the filters but they're just clogged up again.

Have you drained the fuel tank via the big drain plug at the bottom?

 

[DalekEngineer]

Yes, I completely drained all the fuel poured some gas in it and it washed some crap out but I’m sure there was still more crap in the fuel tank

 

[Floridianson]

Fuel does not really flow from the return line on the injectors it more just burps just a bit. There are something you are going to have to check but myself start with checking the timing. Remove the oil fill cap and it helps to have two people but rotate the motor over till you can see the #2 exhaust valve just start to open. This will be the valve that when you look down the oil fill hole and look for the valve that is just forward of the oil fill hole. When it starts to drop then the balancer lines should be coming up. Find the correct balancer line and line it up to the pointer on the block. Now remove the four bolts from the advance window cover and the mark and line should be on the money. Now look at the head scribe/ red paint mark and it should be one tooth off to the rear. If timing is correct then we can move on to the next look sea problem.

 

[DalekEngineer]

I will check that today after I get home from school and we’ll see how it goes

 

[dmetalmiki]

Exactly what my 5 ton has done twice.
Ran fine now will not start except on penetrating fluid (With Teflon(I don't like using ether)).
Also our spare Deuce is doing exactly the same.
We have tried everything.
E V E R Y T H I N G!
They both start on fluids and run fine but will never re-start hot or cold.
I have New hydraulic Heads on the way.

 

[DalekEngineer]

The line in the advanced window cover is about an 1/4” towards the motor but the red mark on the HH is lined up nice with the harmonic balancer on the correct timing mark. With the advanced timing mark on the pointer the red tooth is one or two teeth off. The fuel shut off it about in the 6:30 to 7:00 position, I am not getting fuel up to the secondary filters when I turn on the pump so I’m guessing that’s my problem and it might be because I’m on kind of a hill so it might not be picking up fuel in the tank?

 

[gimpyrobb]

Yup, make sure you have enough fuel in the tank first. Sorry I skipped that one.

 

[Floridianson]

Yup, make sure you have enough fuel in the tank first. Sorry I skipped that one.

Yep only sail boats run on sail boat fuel.

 

[DalekEngineer]

I’m not completely stupid I did open the fuel cap and I could see fuel I just didn’t think it’s on a hill, anyways that you all I’ll let you know if that was just it

 

[50shooter]

Morning

Had similar issues two years ago after firing it up after 5 year sit. The diesel had gummed up the mech. fuel pump. I removed the fuel line from the mech. pump that feeds the secondaries. The fuel only trickled out the output side with the in tank pump running. I squirted Acetone in there, let set for about an hour or so. Turned the power switch back on and the in tank pump literally shot fuel out the output side now. Reconnected the secondaries fuel line and bleed them, truck fired up instantly.

Worth noting, after sitting that long all the fuel system was shellaced (s/p) I even had to replace the in tank pump, it was like it have been glass coated. All 3 filters were crap, fuel lines were pretty decent but had signs. Bleeding the air out of the system is key. I find it helps to have someone with a flashlight watch the fuel lines going to the secondaries. When the truck would start to fall on it's face, the witness always saw air bubbles in the line. Air will make it run great and then cause it to fall on it's face.

Good Luck

 

[DalekEngineer]

But if it had air in the line how would it get there? And if there was air it would only be able to run for a very short time till the air got to the injectors?

 

[rustystud]

I agree with 50shooter. Check the injection pump "booster pump". They are often neglected. Due to their robust build they can take a lot of abuse, but they will fail eventually. The in-tank fuel pump cannot build the pressures the injection pump needs to operate properly. You can sometimes get away with a bad in-tank fuel pump but never the "Booster pump" .

 

[DalekEngineer]

I’ll have a look at that sometime this week, that’s you.

 

[Floridianson]

If you have pretty good flow of fuel at the bleed screw between the secondary and final or you gage it and have your 4 to 7 psi it should at least fire off. Then the booster pump will be kicking in when the rpm start to come up.
When you took the Head apart did you remove everything like the plunger. Last week a member took his apart but when he installed the plunger and plunger guide he had it 180* off. When taking the head apart you must watch the way the plunger guide / plunger is installed in the drive gear. That would be a first around here if this is the case two plungers put back 180* out in one week.
I just happen to have a Head here at my desk.
Looking at it lets pretend we line up the red scribe mark just about in the middle of the window or cut out and where it might be real close to correct timing if we were checking timing or see pic. Then we turn the head keeping it on the same plane but so we can just see the plunger guide and you should just be able to see the writing stamped on the plunger guide. If you can see it on the left side it spells out Aline but you can only see ALI and under that it spells out plunger but all you can see is PLUN to the left side under ALI looking at the guide. This plunger and guide is installed correct. Now if writing was upside down and the ALI / PLUN was on the right side you plunger and guild are installed 180* out.

 

[DalekEngineer]

I’m 99% sure I put it back together correctly, tomorrow I’m going to fill the fuel filters with fuel and see if she starts. If she does and I believe she will I will see if she still dies out of nowhere.

 

[Floridianson]

I’m 99% sure I put it back together correctly, tomorrow I’m going to fill the fuel filters with fuel and see if she starts. If she does and I believe she will I will see if she still dies out of nowhere.

You do not need to fill the filters that is the job of the in tank fuel pump. Turn on just the in tank pump and open the bleeder screw that is in between the secondary and final fuel filter. There should be a good flow of fuel when all the air is pushed out of the system. We also can put a gage where the bleed screw is and check the in tank fuel pump is putting out the 4 to 7 psi. We also do not need to bleed the injectors.