cat deezil problems

trx250r180

The Junk Peddler
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anyone ever work on these 3116 inline 6 engines ? i had bunch of raw fuel pouring out the exhaust ,put the heat gun on the exhaust man 1 and 6 were real cold ,ok replace the injectors ,pulled them out ,the o-rings on tips were blown on those 2 injectors ,replaced the 2 injectors and all 6 o-ring tips ,ok #1 is getting warm now ,#6 still 40-50 degrees cooler than the other 5 ,checked injector spring height adjustment ,its same as other 5 ,has a bad miss driving still ,like 1 dead hole ,possible i burnt a valve when it was over fueling ?or fuel mixture wrong still ? anyone have any ideas ? it's engine in my roll back tow truck ,i'm hurting bad not having this on the road ,these are mechanical injectors ,there is another adjustment to sync them ,i can see all the tips that you measure when adjust ,they all look real close but i have not put a dial indicator on them yet #6 is firing now but just not getting as warm ,is 160-170 degrees on the manifold when the others are in the 210-220 range idling
 

mdavlee

How the heck did this take so long?
Jan 10, 2012
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Taking the injectors to a diesel shop for them to test and set them all even would be the best way to get them set right. There could be trash in it and blocking s feed hole.
 
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trx250r180

The Junk Peddler
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Taking the injectors to a diesel shop for them to test and set them all even would be the best way to get them set right. There could be trash in it and blocking s feed hole.


the cold hole has a remaned one in it ,i set the injector timing height ,but did not time it with the others ,is the timing that critical ?being off a few thousandths? thing runs like one holes dead till hit about 2500-2800 rpms ,gets better but not right by no means ,this engine does not normally run that high rpms,2k-2400 most of the time
 
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mdavlee

How the heck did this take so long?
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Unless you've got a pop off test stand it will be hard to get them even. There's some diesel shops out there in your area that should be able to help you. I don't know what the pop off on those are but a comparable sized Cummins is around 280 BAR.
 

trx250r180

The Junk Peddler
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this is real similar to my head ,vid is short so does not show much

[video=youtube;FdwmeUyCul4]https://www.youtube.com/watch?v=FdwmeUyCul4[/video]
 

naked arborist

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Merica kinda... So. Joisey
They gota be right man. That brought some back memories. They're spot on about the pop pressure and the pattern. If the pattern is even a little to tight or lacks good atomization your ✖✖✖✖ed. They all MUST match. Keep bleeding it till it runs clear. No foam. It will never work right if you have any air/foam in them.
 
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Now about that injector test stand business .I suppose it just depends on how much of a junk yard dawg a person is .

I have rust in my veins and grease all over me so I guess I fit the bill .This is what I use .It's just a hand hydraulic pump filled with diesel fuel from a Black Hawk portable hydraulic press ,good for 3,000 PSI .With a high pressure valve and a 3,000 PSI guage .

The praticular injectors I set up had a cracking pressure of 1550 PSI as per factory specs .
 

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I would almost speculate not seeing the actual injector that probabely the nozzles aren't sealing correctly .Depending on the design they can be reworked by lapping .Often times though again depending on design the replacement nozzles can be installed much more simpley than trying to rework them .

For example the type injectors I reworked the replacement nozzles were 90 bucks a pop but that was over 20 years ago .At the same time a complete injector was over 350 a pop .They are probabley Denso nozzles .
 
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trx250r180

The Junk Peddler
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i'm 90% sure #6 cylinder is the problem ,it has a remmaned injector in it ,i replaced 1 and 6 with new ,it is 50 degrees cooler than the rest with a heat laser on the exhaust manifold,i have been reading online some of these engines in boats with 300 plus hours have lost valves ,hope it is not that ,the injector timing is set ,but have not set the fuel flow rods ,i have a friend that is a diesel mechanic ,i don't have any dial indicators that seem to fit in there right to measure all 6 ,i am thinking about swapping injectors 6 and another like 2 or 3 away from the problem ,see if that clears up cyl 6 ,i could have got a bum injector ,that would make me happier than the burnt valve ,
 
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trx250r180

The Junk Peddler
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well i was 90% wrong ,pulled the injector ,put an air blow tip in there held pretty good pressure ,i remembered #2 injector tip looked beat up when i pulled them so i checked that one second ,has some air coming up the intake when i blow into that hole ,bent or burnt intake valve ,i am wondering if something got sucked in or fell in during a service ,usually an exhaust will burn from what i am used to ,i can push the valve spring down and can feel the valve come up and seat some ,so it's bent or burnt ,head has to come off now :whathefrik:
 
Say the way that head is made it might be possible to roll the engine near top dead center and use a chunk of rope through the injector hole to hold the valve up .Despring it and roll it around .It might have a piece of crud stuck in it .

FWIW I had a valve on a Ferguson break the retainer .The way it is made the stem is long enough it cannot swallow the valve .I stuffed a rope in it and made a new retainer on my lathe and put it back together with no problem and never removed the cylinder head .Not that it matters but some place in my zillion and a half pictures I captured it on camera .
 
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naked arborist

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Try this. Fill it with air and remove the spring. Then gently set the valve down on the piston ATDC. Check the seat if you can get the valve down enough to spin it. If the seat is true and not burnt you know the head needs work before the tear down. Good Luck on a burnt or bent valve. Be sure both valves are shut tight and the rockers are off. Just makes the job easier with both rockers off, more room to work.
 

trx250r180

The Junk Peddler
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today's monday ,one of busy days at the shop here ,i am going to try to start tearing it down ,i will get the exhaust man off first and look in there ,see if can see anything obvious ,i was able to adjust the valves ,there was wiggle in the rockers still ,so bent i am not sure ,air was not going full bore out ,but that injector tip had some damage so something was bouncing around in there ,i am not looking forward to pulling the head ,but don't have much of a choice ,i need this truck going ,it's my main truck for hauling salvage
 
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Hedgerow

Mizzurruh Saw Gangsta
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today's monday ,one of busy days at the shop here ,i am going to try to start tearing it down ,i will get the exhaust man off first and look in there ,see if can see anything obvious ,i was able to adjust the valves ,there was wiggle in the rockers still ,so bent i am not sure ,air was not going full bore out ,but that injector tip had some damage so something was bouncing around in there ,i am not looking forward to pulling the head ,but don't have much of a choice ,i need this truck going ,it's my main truck for hauling salvage

Well... I hope you can become a 3116 expert Brian...
As I have just purchased a 97 GMC with one in it...
Gotta put a dump bed on it for grain and wood hauling...
Hope it lasts a while..:dunno:
 
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