bobinyelm

I am in the middle of a complete rebuild on my 2003 5.9 w/ only 109,000mi due to gouges found on the front of #1 and the rear of #6 cylinders. Otherwise the engine looked like NEW inside (no cylinder wear, pistons were clean w/ no evidence of over heating).

Only symptom was excessive blow-by. Engine ran so smoothly you could barely feel it "run" through the 6spd gear shift lever.

The engine rebuilder will only warranty the new engine if I install new injectors. After calling numerous injector distributors, they ALL say that:

1) There are NO new injectors on the market. They are all rebuilt, including the ones from Bosch (which I confirmed w/ Bosch).
2) Injectors should be routinely replaced at no more than 150k mile intervals, or you are risking your engine, no matter HOW WELL the engine is running. I am quoting the injector distributors.
3) The injector failures are apparently from worn or cracked seats, and result in too much fuel, washing the cylinders dry, causing galling and internal destruction

I am not sure how to know when the injectors fail, since my truck ran SO smoothly even when the cylinder walls had been damaged.

Who makes (rebuilds) the longest lived injectors, or does everyone use the same new parts inside? The prices vary from $300-$425 each, but if they all are the same inside, why not buy the cheapest?

Folks have told me to install a 2-filter pack w/ external pump inline on the frame to the underhood fuel canister, with a 10 micron first, then a 2 micron. I suggested a Walbro and two separate filter holders (using barbed connectors and rubber fuel hose), with 10 and 2 micron canisters, but he said ONLY Air Dog or FASS are worthy.

I would like opinions and comments how to make my NEW engine last more than the 110k my first one lived. In fact, I'd love to see 200k for the engine and the injectors considering how easily I drive the truck, which will never see any HP mods.

BTW, the truck had every scheduled service performed by Dodge dealer, and was treated like a member of the family-zero abuse ever. To say I am disappointed is an understatement.

BTW, both the rebuilder and the injector people say they see lots of destroyed engines between 125k and 150k because of failed injectors. If that's true, you'd think Cummins, or someone, would have offered a "fix." And if an injector is leaking (w/ a smooth running engine) how do you know?

Thanks-
Bob

CRToney

your post doesn't make me feel very comfortable as my #5 injector was leaking fuel into the crankcase somehow. If your oil level goes up then injector is bad and get them checked.

rich

your injectors will last longer if you run a better filtering system. there are plenty of guys getting over 150k running the same injectors just a better filter system. gouges are usaully called by other materials then fuel, galling is caused by fuel but i never had any gouges being caused by fuel alone

bobinyelm

The vertical gouges were about 5/16" wide and maybe 0.15" deep. The metal was just gone, as if it had been scraped off.

No evidence of anything being ingested into the engine.

Didn't pull the pistons to inspect the rings/lands as it was being sent out for total rebuild.

Bob

no_6_oh_no

If only 2 cylinders had gouges and the rest looked good its doubtful the injectors caused the problems. Naybe carbon breaking off the tips becuase it wasn't worked hard enough , broken rings, FOD intot he engine, or ???, could cause that but it wasn't fuel only. Considering how good it ran without all the normal symptoms of injector failure, well, if it walks like a duck and talks like a duck............


Quite a few long haulers getting over 400k easily on these engines with occasionaly replacing failed injectosr, but, filtration is the key. Just about all the high mileage engines are running extra filters or pre-filtering into the stock system.

Rebuilding the electronic injectors at 150k is probably about right. Jerk pump engines needed a reset of the pop pressures to function efficiently in that range also. Fact of life we have crappy fuel and it eats injector seats and other parts. Fact of life the electronics are not gonna last forever running 2 or 3 events on every cycle.

If you really want to compare, the fact that the CR injectors get 150k running 2-3 times more operations at a lot higher pressures than a jerk pump is a step up in longevity. The fact they will last a lot longer with better filtration is a huge jump.

It is what it is with what we work with.

bobinyelm

"Rebuilding the electronic injectors at 150k is probably about right. Jerk pump engines needed a reset of the pop pressures to function efficiently in that range also. Fact of life we have crappy fuel and it eats injector seats and other parts. Fact of life the electronics are not gonna last forever running 2 or 3 events on every cycle."

I only wish the cost of rebuilding CR injectors were comparable w/ mechanical injectors and I wouldn't mind doing even every 100k!!

My daily driver car is a flawless '96 (in and out) that is worth less on the market than just 6 injectors in my hand. That's ugly!

Given the way the engine ran, the way it looked inside, and the fact I wasn't "making oil," I too doubted that the injectors trashed the engine, to be completely honest.

BTW, no carbon to speak of visible inside the cylinder or head, but I guess there could be some in and around the rings where it would only be visible w/ the pistons out.

The combustion chambers looked like a nearly new engine. No sign of anything hard dinging the head combustion roofs as it banged around before being spit out. Remarkably clean engine except for the missing metal.

Bob

CoastalDav

I'm no diesel machanic. I have a basic understanding of how this stuff works. It would seem to me that the gouges in the cylinder wall(s) (I assume that's were it was) was caused by the injection pulse being directed at the gouge area which is not were it should have been going.

So, I assume something was on the tip of the injector that diverted a fuel stream in that direction (not atomized).

The pressures seen in the CR system are high enough to cut steel without any problem. This type pressure is used everyday to access steel fuel storage tanks that have not be cleaned. (No Sparks or heat)

I really don't see carbon making the gouge. I see carbon on the injector tip or damage to the tip, causing the diversion from an atomized spray to a straight stream.

I feel it was fuel that caused the problem or possibly an additive that did not fully combust in the chamber. Diesel fuel is still way to dry. To me it feels like mineral sprits and not the way diesel fuel use to.

I don't know what the API spec for viscosity is for diesel fuel, but adding any type of additive will change that. That may increase the pressure at the tip during the firing cycle. That could damage the tip as well.

Sorry for the long none technical post of my 2 cents.

Dave

no_6_oh_no

If carbon is not hard enough to gouge the cylinder walls how long do you think it would would it last in a high pressure spray? Not long would be my guess.

The spray patterns are diverted enough by build up to hit the cylinder walls but rather they are diverted back on themselves and atomization is reduced as is the pattern. Thats the typical scenario.

It would have to be a major ongoing failure to divert injection streams on to the cylinder walls and it would instnaly be noticeable in drastic power loss and LOTS of smoke. Once the pattern gets outside of the piston bowl it will smoke like a freight train and it won't quit. Pretty hard to miss that.

My guess would be carbon buildup on the ring lands and possibly the piston crown could contribute. Carbonized elements are goign to be pretty hard and once they get jammed between the piston and wall they can wear things pretty good.

Another possibility would be the piston scuffing the cylinder but that should be obvious on both the top and sides of piston.

A frequent problem thta has popped up is the ring lands breaking causing excessive blow by and cylinder damage. That could be fueling or timing or just plain too much heat. Doesn't seem to be a contant pattern ther.

bobinyelm

Bob

RJ285

My uncle had to do the same thing on his '03, at around 200k though. He said that they made changes to the original design so it makes would make sense that the only injectors available are rebuilt.