D6H 3zf00772 sputtering throughout all rpms engine hot or cold. Checked fuel lines, filters, and injectors. It's not a dead miss. Just a sputter. Small power loss. You can crack the injector lines and there's no 1 injector that allows down the engine any more than the others. No smoke. Just the normal light black smoke when you let off the deaccelerater. Checked the valve lashing. Everything is in spec. Had a lot of carbon build up on my injectors. Any other ideals on things to check? Dozer starts fine. Kinda has a little sputter when you start the engine sometimes instead of popping right off but it still starts without having to hold the key any longer than normal.
Basic questions: - Engine hours? Injector hours same as engine or less? If less, how long ago were they replaced and are they OEM or aftermarket? Problem started suddenly or built up over time? Any recent repairs or service work? Does the engine consume oil at all? Air filter replaced recently? Have you checked fuel pressure?
Unknown engine hours. Approximately around 8000. Doesn't hardly use oil usually only when it gets close to an oil change. Injectors were changed out yesterday. The ones before that were cat reman replaced 2 and a half years ago and went back with cat reman. I don't think the injectors were an issue. Only 4 didn't test good. New injectors made no noticeable difference. Maybe a little less smoke on acceleration but it's hard to tell exactly with a light spudder . Turbo rebuilt injector pump and injectors 2 and a half years ago. Other than that oil changes around every 150 - 200 hours. Transmission oil changed and transmission screens cleaned. Oil and transmission cooler cleaned . Approximately 250 hours ago. Fuel pressure hasn't been check.
Just for completeness........ Recent air filter servicing? Problem started sudenly or built up slowly over time? What happens exhaust smoke-wise if you go straight from Low Idle to WOT.? Is it burning more fuel than normal.? TBH my first suggestion would be to check fuel pressure.
Yes good air filters. It started all at once. I went into a pile and when I went wot it started all of a sudden. Normal small puff of black smoke comes out from idle to wot . smoke hasn't changed at all since problem started
Also hand primer pump changed after dozer started sputtering .
My mechanic thinks it could be maybe a crack in the head gasket between bores or maybe a piece of carbon stuck under a valve not allowing it to close all the way. He doesn't believe it's fuel related.
Without having checked fuel pressure I would disagree with your mechanic. It might not be fuel-related but right now nobody can say for sure if it is or not because all the possible tests to eliminate the fuel system as the root cause haven't been done. You said the valve set had been done but it changed nothing. Related to the idea of something stuck under a valve surely that would show up in a valve adjuster screw way different in height to the rest..? So if your mechanic did the valve set surely he'd have spotted something like that. Do you do oil analysis..? If not how about taking a sample and having it analyzed for water, glycol, or fuel in the oil..? That would give you a good idea if something was getting where it shouldn't.
That's why I was asking on here cause I thought it might be fuel related. I turned the motor over for him while he set the valves. They weren't bad at all. I had set them myself about 2500 hours ago when I replaced turbo and injector pump. I've been pushing this morning with it and it runs the same temp but has a slight power loss. I have great flow from the tank through the hand primer pump. Haven't checked fuel lines beyond that.
In that case get the gauges on the fuel system and check the pressure, plus have an oil sample analyzed as recommended above would be my thoughts.
How much pressure should I have going into my injector pump?
Measure the pressure at the 1/8" pipe plug on the secondary fuel filter head. At High Idle RPM the pressure should be a minimum of 15psi.
Ok I'll check that. Thanks
Exhaust restrictions?
Any ideal to what a part number would be for a guage that you can screw into that port and leave it there permanently. I've seen them before on filter bases but can't find a part number for them.
I think if you did that the vibration would kill it in short order. There's a reason why pressure gauges are generally mounted in the dash panel, or at least somewhere where the vibration is not quite so pronounced.
I have seen a number of oil pressure gauges direct mounted to an engine fitting. Seemed to work all right over the lifetime of the engine.
Going to check fuel pressure tomorrow. Had to go purchase a gauge that would show low psi. Mine started at 50. Also there is a noticeable noise. Almost sounds like an exhaust manifold leak with the miss but there is no exhaust leak. The more load on the engine the more noticeable. I know when diesels misfire they make different sounds but I didn't know if that would help narrow the problem. Been over 2 years since I've had any engine trouble on my machines. Maybe I'm over thinking it
Have you happened to remove the oil filler cap while it's running? First thing I do when I hear something amiss. I sense more in-depth surgery in your future.
I'm late into this, but have you found the pre strainer/screen between the tank and transfer pump and cleaned it? Been there with a 5H before.
Rzucker I've checked everything on fuel system right up to transfer pump .Plenty of fuel to there. Hand primer pump was in rough shape so went ahead and changed it incase it was sucking air. Changed secondary filter and cleaned the primary one. Still no difference.
Haven't took off oil filler cap while running. I need dozer for another 60 hours to finish the job its on. Been on same job since first of the year and it's close to a hour and a half from where I can get parts. Hate to start tearing into it but also don't want to destroy the engine trying to finish the job
What you're looking for when you remove the oil cap is excessive or pulsating smoke/blow-by, and audible clues if something is out of the ordinary.
Good thinking. Haven't thought of checking that. My mechanic thinks it's internal .Like a head gasket blown between cylinders or a valve leaking. I've just been trying to cover everything on the outside of the motor before going in.
If it makes a noise like exhaust leak it could be an exhaust valve not seating properly and leaking a bit. A video with sound would be nice.
I'll take a video tomorrow or Monday. Can you upload videos on here?
No. Easiest way I've found is to upload to YouTube, and then post a link. I thought of something else, only because we had it happen last fall. Not sure it could happen to a 3306, but we had an N14 that burned the head gasket through to the outside. It happened between the heads.
when these b models take a crap, you will find its usually started at the number 3 or 4 exhaust valves, they run hotter then the rest.turn engine over without fuel if its making a hissing noise usually bad exhaust valve seat. if no hissing run sight glass on fuel line to check for air bubbles, no bubbles then go to fuel pump. looking forward to video
Fuel pressure looked good. Starting to head into motor. Only thing I've found so far is exhaust manifold gasket gone on #1 cylinder
OK, all good. Diagnosis is nothing more than a process of eliminating possibilities until you find the root cause. I think it would've been frustrating for you to get into the engine to find nothing then discover the fuel pump was foobarbed.
Yes usually it's easy to overthink things I've realized. Fuel was around 35 to 40 psi at idle. Exhaust manifold gasket is completely gone at #1 cylinder. I'm starting to think that maybe the whole problem. Cause I just have a slight power loss and the noise is coming from front of engine
Actually got the manifold off. First 4 cylinders were a leaking bad .
Exhaust manifold gaskets fixed my misfiring. Had to double up on gaskets cause they had been leaking so long it ate a little off my manifold. Guess that's why my carbon build up was bad. Not enough exhaust through turbo. Didn't even break a stud off. Pb blaster all the way .
Play the lottery with all that good luck
Cat even sent an extra set of gaskets on accident. I was lucky today. I may just go by a lotto ticket. Gonna buy some newer nicer not so worn out equipment if i win.