Injector Fouling cure

[sandcobra164]

I've got a very low mile M1028 that runs great except for 1 issue. It will occasionally foul an injector and the only cure is to floor it. The increase in fuel delivery will cause the dead cylinder to start firing again everytime. It's only got 2800 miles on and am I'm sure they're not 102800 (reference NOS USMC M1028 thread) for pics. I've talked to a long time 6.2L mechanic / fan and he's advised me that I can go for a quart of Dexron III, Clean motor oil or SILO Diesel conditioner added at their recommended rate will cure the issue. He did say that the SILO contains alcohol to dissipate water and is not great for the injector pump head but I told him that the military 6.2 was supposed to have a hardened staynadyne pump. Anyhow, short of replacing injectors, what product would you recommend. The truck did alot of sitting in Norway with JP-8 in the tank. I've driven about 600 miles using Power Service in the silver bottle at about double their prescribed treatment. There is no water in the fuel according to the light on the dash that comes on along with the glow plug wait light. The issue is better but not cured after the Power Service additive.

 

[papabear]

I have vast knowledge in that area sandcobra and it CANNOT be resolved.

You just need to bring that truck to the compound and we will trade ya sumpin fer it

 

[sandcobra164]

Larry,
The wife saw this and said the only way I could trade is if I got "The Proud" and a fuel card for a year along with it and quite a few greenbacks!!!!! In other words, she said not a chance in that fire pit below us.

 

[papabear]

Larry,
The wife saw this and said the only way I could trade is if I got "The Proud" and a fuel card for a year along with it and quite a few greenbacks!!!!! In other words, she said not a chance in that fire pit below us.

Oh...well the fuel card and a few greenbacks can be had...but YOU KNOW Proud American can't be had...by anybody...ever!!!
(Til I die...then MB will prolly sell her for scrap)

 

[91W350]

I have a 36,000 mile M1008 that I have put about 12,000 miles on. It used to do the same thing and I tried all the pour in remedies. Rich posted that I was wasting my time and money and I should just put in a set of injectors and be done with it. Turns out he was right, I think he referred to additives as snake oil. At any rate, mine waited until I was 700 miles from home in -18 degree weather, between storms to lay down and not come back. I think Westy is right, just treat it right and have the injectors done, replace them, or install the rebuild kit. Glen

 

[jdemaris]

It will occasionally foul an injector and the only cure is to floor it. The increase in fuel delivery will cause the dead cylinder to start firing again everytime. It's only got 2800 miles

I told him that the military 6.2 was supposed to have a hardened staynadyne pump.

I doubt you've got a "fouled" injector . . . and there is no such thing as "hardened" Stanadyne injection pump.

Many diesels use injector nozzles with multiple small holes that ARE subject to plugging. The 6.2 does use that type of injector. It uses a "pintle" injector with one large opening. When an injector is faulty, and/or worn, it will do exactly as you described. The problem is likely metal wear and/or a bad seal, not soot. Considering a new injector nozzle will cost $8 to $14 - it's kind of a no-brainer. Just change the nozzle.

In regard to Stanadyne pumps- the weakest part of the pump is the distributor section. There is only one type, i.e. no "heavy duty" replacement.
Standadyne does offer an "arctic fuel" kit that uses hardened low-pressure pump vanes - and they have nothing to do with the high pressure injection part of the pump. That "arctic kit" is what the US Military put into many pumps to see if it would make them last any longer with the JP8 military fuel. The end result was - the kit makes almost no difference in longevity.

Any pump that has had the "arctic fuel" kit insalled will have "1.2 cSt" on the ID tag.

Here are just about all the Stanadyne pumps used on GM V8 diesels by the military. Some have the arctic kit and some don't. With or without, the pump will suffer from thin low-lube fuel.

Military pumps:
DB2829-4267 14077179 1984-85 CUCV (Military)
DB2829-4305 14077134 1984 CUCV (Military)
DB2829-4355 23500014 1984 HMMWV (Military)
DB2829-4386 23500256 1984-85 CUCV (Military), HD C/K, D Truck - 1.2 cSt
DB2829-4440 23500276 1985 HMMWV (Military) - 1.2 cSt
DB2829-4471 23500398 1985 HMMWV (Military)
DB2829-4520 23500413 1986-87 CUCV (Military)
DB2829-4521 23500414 1986-87 CUCV (Military), HD D Truck - 1.2 cSt
DB2829-4523 23500415 1986-89 HMMWV (Military) - 1.2 cSt
DB2829-4524 23500416 1986-89 HMMWV (Military)
DB2829-4847 10149679 1990 HMMWV (Military)
DB2829-4848 10149634 1990 HMMWV (Military) - 1.2 cSt
DB2829-4878 10149633 1990½ HMMWV (Military)
DB2829-4879 10149634 1990½ HMMWV (Military) - 1.2 cSt
DB2831-5209 12555697 1995-97 HD (Military) - N/A, 1.2 cSt
DB2831-5485 12561514 1998-00 HD (Military) - Turbo, 1.2 cSt

 

[sandcobra164]

metal wear or varnish from sitting so long? I'm convinced this truck has less than 3,000 original miles and have pictures and documentation to back my thoughts. Could a good fuel additive that dissolves the varnish help? Trust me, you've got my attention as you seem to be quite knowledgeable and there's no sarcasm in that statement. I'm all eyes or ears.

 

[jdemaris]

metal wear or varnish from sitting so long? I'm convinced this truck has less than 3,000 original miles and have pictures and documentation to back my thoughts. Could a good fuel additive that dissolves the varnish help? Trust me, you've got my attention as you seem to be quite knowledgeable and there's no sarcasm in that statement. I'm all eyes or ears.

If you can get some B20 bio-diesel, it's likely to loosen varnish as well as anything - in the injectors. I just doubt varnish is your problem. It will also eat up old return fuel hoses unless they are Viton.

Like I said, the 6.2 uses pintle injectors. Each uses one big self-cleaning injector port. I guess anything is possible, so I'm not going to say it "can't happen." I've changed bad injectors in 6.2s with over 200,000 miles on them. They were clean where it counts - just worn out. When injectors in 6.2s get real bad, the engine will skip and knock something awfull

I doubt your engine really has those low miles. But, if it does and your problem truely is just from varnish? Seems driving it would fix it in quick order.

I'd put a 100 miles on it and see if it gets better. If not? Loosen each injector line, one by one with the engine idling until you find the one that's not firing. Once you know which one - it's less then an hour's work to pull the injector assembly out, put in a nozzle, and reinstall.

On any 6.2 that reaches 150K miles- I always change all the nozzles with new as a matter of routine maintenance.. Changing just one is something I rarely do.

 

[sandcobra164]

10-4, it's just an intermittent problem, as in maybe once or twice in 40 miles of driving. It only seems to do it once warmed up and you can easily hear when one cylinder drops. A quick jab of the accelerator and she's cleared up and hitting on all 8 again. The truck was stored in a cave in Norway for roughly 20 years as part of the Marine's prepositioned equipment and it used to have a large fire extinguisher on the bed. It came back to the states about 2 years ago in a 20 foot ISO container with less than 1,000 miles. Heck, the pioneer tools behind the seat look as though they've never been removed and the factory build sheet is still in the glove box.

 

[davidkroberts]

im a big fan of Seafoam IMHO. I put it in everything. If it can clean up the idle on my Gama Goat it is majic in my book.

 

[Brad M]

Many diesels use injector nozzles with multiple small holes that ARE subject to plugging. The 6.2 does use that type of injector. It uses a "pintle" injector with one large opening. When an injector is faulty, and/or worn, it will do exactly as you described. The problem is likely metal wear and/or a bad seal, not soot. Considering a new injector nozzle will cost $8 to $14 - it's kind of a no-brainer. Just change the nozzle.

jdemaris, What's the Part Number for that nozzle you mentioned?

 

[Brad M]

Never-mind, found your reply in the "anyone know the injector number?" thread with it.

Guess it wouldn't hurt to put the info here also but I'll leave that up to you. Thanks and sorry if I hijacked this a bit.

 

[ranchhopper]

I have a 1008 that had a bad injector I ran some seafoam through it and just plain drove it all the time eventually the injector stuck fewer and fewer times no it runs like it never had a problem.

 

[ssgtcampbell77]

I doubt you've got a "fouled" injector . . . and there is no such thing as "hardened" Stanadyne injection pump.

Many diesels use injector nozzles with multiple small holes that ARE subject to plugging. The 6.2 does use that type of injector. It uses a "pintle" injector with one large opening. When an injector is faulty, and/or worn, it will do exactly as you described. The problem is likely metal wear and/or a bad seal, not soot. Considering a new injector nozzle will cost $8 to $14 - it's kind of a no-brainer. Just change the nozzle.

In regard to Stanadyne pumps- the weakest part of the pump is the distributor section. There is only one type, i.e. no "heavy duty" replacement.
Standadyne does offer an "arctic fuel" kit that uses hardened low-pressure pump vanes - and they have nothing to do with the high pressure injection part of the pump. That "arctic kit" is what the US Military put into many pumps to see if it would make them last any longer with the JP8 military fuel. The end result was - the kit makes almost no difference in longevity.

Any pump that has had the "arctic fuel" kit insalled will have "1.2 cSt" on the ID tag.

Here are just about all the Stanadyne pumps used on GM V8 diesels by the military. Some have the arctic kit and some don't. With or without, the pump will suffer from thin low-lube fuel.

Military pumps:
DB2829-4267 14077179 1984-85 CUCV (Military)
DB2829-4305 14077134 1984 CUCV (Military)
DB2829-4355 23500014 1984 HMMWV (Military)
DB2829-4386 23500256 1984-85 CUCV (Military), HD C/K, D Truck - 1.2 cSt
DB2829-4440 23500276 1985 HMMWV (Military) - 1.2 cSt
DB2829-4471 23500398 1985 HMMWV (Military)
DB2829-4520 23500413 1986-87 CUCV (Military)
DB2829-4521 23500414 1986-87 CUCV (Military), HD D Truck - 1.2 cSt
DB2829-4523 23500415 1986-89 HMMWV (Military) - 1.2 cSt
DB2829-4524 23500416 1986-89 HMMWV (Military)
DB2829-4847 10149679 1990 HMMWV (Military)
DB2829-4848 10149634 1990 HMMWV (Military) - 1.2 cSt
DB2829-4878 10149633 1990½ HMMWV (Military)
DB2829-4879 10149634 1990½ HMMWV (Military) - 1.2 cSt
DB2831-5209 12555697 1995-97 HD (Military) - N/A, 1.2 cSt
DB2831-5485 12561514 1998-00 HD (Military) - Turbo, 1.2 cSt

Where are you getting your injector nozzles from? Everywhere I look is priced at a minimum of $75???

 

[ODdave]

sounds like a sticking pintle to me, just replace the injector. if you just replace the nozzle you stand a very good chance of the "cracking" pressure being incorrect, This is not good for your engine. Your best bet is to get new nozzles and have them balanced as a set.

 

[mr.travo]

Dave, how much does Seafoam run?

 

[ssgtcampbell77]

Mr. Travo, you can get seafoam at Oreillys for around $10 a can.

 

[dozer1]

Sounds like an awesome truck Joseph. The seafoam trick might just do it as I know that stuff really has a devoted following. Did the fuel smell pretty nasty that it had in it at first? Sounds to me you are on the right track to getting it straightened out.

 

[sandcobra164]

I know this is digging up my own old thread. Everytime this truck has acted as though an injector was bad, it'd smoke out of the driver's side tailpipe until it cleared up. I've got another idea. Rather than an injector problem, I believe I'm the victim of a glow plug tip in the pre-combustion chamber. I went to replace them all today and could only do 5 and #3, Driver's side second back is missing about 3/4" of his tip. It came out without any force so I imagine the tip occasionally disrupts the spray pattern of the injector which leads to incomplete / delayed combustion in that cylinder. I'll be pulling that injector this weekend along with possibly 3 others (#2, #4, and #5) as I attempt to get those glowplugs out.

 

[doghead]

I'd say it's an injector issue burning off the GP tip.

Change out those injectors.