• Steel Soldiers now has a few new forums, read more about it at: New Munitions Forums!

  • Microsoft MSN, Live, Hotmail, Outlook email users may not be receiving emails. We are working to resolve this issue. Please add support@steelsoldiers.com to your trusted contacts.

8V92 Coughs but Won't Start (SOLVED!)

BaconFarms

Active member
Steel Soldiers Supporter
60
140
33
Location
Eagle River, WI
Fuel filters are from 2020. I will pop them off and take a look.
Slime don't care how old the filters are. The dozer had a small cartridge filter and the slime was easy to see, and it had plugged it up enough to not start, etc. Would start on ether and then die. It's a place to look. Gelling will look cream colored, slime dark, maybe black..
 

matt2491

Member
31
32
18
Location
Billerica, MA
Replaced the fuel filter today. Old one (2020) was about 3/4 full upon removal, but also rusty inside. I traced the supply line from the tank and I guess someone bypassed the fuel/water separator at some point cause I can't find it. The fuel goes straight from the tank to the pump then to this secondary filter and finally to the injectors.

IMG_1854.JPG

I filled the new filter to the brim with fresh diesel before installing. I'm not sure how to properly prime the system so I just went ahead and cranked the engine over a bunch. No change in symptom.
 

wrenchturner6238

Active member
325
29
28
Location
Beaver Oklahoma
I would plumb the fuel lines properly once you get it running. You can almost use anything that can move fuel through the system so it returns to the tank. I would not run the engine until after unhooking what you use to prime unless you have a check valve in line
 

87cr250r

Well-known member
1,267
1,988
113
Location
Rodeo, Ca
If you have corrosion in the fuel filters you may have stuck injectors. Pull a valve cover (the gaskets are reusable) and verify the injectors aren't stuck down. You can also exercise the fuel rack. Any stuck injectors won't change position.

If you do have stuck injectors all is not lost. I believe there is a procedure to use methanol to free up stuck injectors.
 

davidb56

Well-known member
1,020
1,237
113
Location
Bonners Ferry Idaho
Replaced the fuel filter today. Old one (2020) was about 3/4 full upon removal, but also rusty inside. I traced the supply line from the tank and I guess someone bypassed the fuel/water separator at some point cause I can't find it. The fuel goes straight from the tank to the pump then to this secondary filter and finally to the injectors.

View attachment 886740

I filled the new filter to the brim with fresh diesel before installing. I'm not sure how to properly prime the system so I just went ahead and cranked the engine over a bunch. No change in symptom.
did you physically check to make sure the fuel pump is actually pumping fuel yet?
 

davidb56

Well-known member
1,020
1,237
113
Location
Bonners Ferry Idaho
If you have corrosion in the fuel filters you may have stuck injectors. Pull a valve cover (the gaskets are reusable) and verify the injectors aren't stuck down. You can also exercise the fuel rack. Any stuck injectors won't change position.

If you do have stuck injectors all is not lost. I believe there is a procedure to use methanol to free up stuck injectors.
they are also pretty easy to remove, disassemble and clean too. care must be taken on adjusting the fuel rack.....its been 40 years since Ive messed with them. I did it in the kitchen (clean stainless tables) of Moores Riverboat Restaurant years ago, for the owners old Lima crane dredge he used to keep the boat floating. It burned up years later.
 

matt2491

Member
31
32
18
Location
Billerica, MA
I don't think the pump is pumping. So I tried priming the system using a vacuum brake bleeder but I don't think I'm doing it right. This is per the TM which says to pull a vacuum from one of the ports on the secondary fuel filter housing. Of course, there is a special tool designed for this, but I thought the brake bleeder might work. Anyway, I'll pump the brake bleeder a bunch and it will draw a bunch of diesel into the canister, but once I stop, the system pulls all the diesel I just pumped out back in...

IMG_1891.JPG

From the TM:

Screen Shot 2022-12-23 at 5.48.35 PM.png

Screen Shot 2022-12-23 at 5.48.31 PM.png
 
Last edited:

wrenchturner6238

Active member
325
29
28
Location
Beaver Oklahoma
I have never use a vacuum to prime. If you were going to do that you would need to pull from the return line for it to be really effective. I normally use a hand pump like I put in a few posts up.

Yes unless you break the vacuum at the line at the fuel tank it could sure pull all your fuel back out to the tank.
Like I said I have not tried a vacuum pump for this but I think if thats what you have put it on the return line and try it. This may take a bit of pumping but it should pull it through the heads and injectors.

The main thing you want is full fuel filters, pump, heads and injectors. If you pull on the return line you will get this if you have no leaks. It looks like if you can pull to your filter housing ( that part is good)
 

wrenchturner6238

Active member
325
29
28
Location
Beaver Oklahoma
To be honest I don't know if it would work or not.
It might work I just am not sure. Because you do need to build a little psi to prime Because of the clearance in the fuel lift pump.

Years ago I did use a tall thumb pump oil can with a hose on it to prime an engine.

On my m931 there is a hand primer pump mounted right behind the injection pump.

Sometimes when you use the correct it's kind of difficult to think of alternatives
 

Attachments

wrenchturner6238

Active member
325
29
28
Location
Beaver Oklahoma
How they use it on the cummins is different than how I would use it on yours because they use the suction to draw the fuel up the suction line of the pump. On yours you need to force the air out of the heads and injectors
 

87cr250r

Well-known member
1,267
1,988
113
Location
Rodeo, Ca
Your engine has a gear pump transfer pump and unit injectors. This system is very good at self-priming. You're chasing the wrong problem here. Heck, these Detroits don't even use pressure regulating valves. They have a simple orifice in the return manifold. If you've got fuel pressure you don't have a supply problem.
 
Top