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D6c cat loss of oil pressure

gary808

Well-Known Member
Joined
Oct 8, 2009
Messages
218
Location
hawaii
Occupation
operator,maintanence ,fabricator
Are the pump and injectors original? Sorr I have missed alot of the thread.
I have seen a 3306t in a d7 have a injection pump isue and a day later spin a rod bearing. And a have personally seen a cat 966b toss a rod then have a rebuilt engine dropped in with the same pump and have the same cylinder lock up. That one was never solved and the machine is still sitting. Maybe they screwed up on the rocker arms. The owner gave us the machine but I haven't gotten around to hauling it. I've also witnessed a burnt cylinder in a old d7e 48a after a injector cup unscrewed and washed the cylinder during operation causing a piston failure.
Anyhow just tossing it out there not saying this is the cause but you never know.
 

DoyleX

Senior Member
Joined
Feb 2, 2013
Messages
571
Location
Minnesota
Occupation
Lever Puller, Gear Jammer, Pipe Twister
So Ziegler is looking at answers from the knowledge pool of this site because they do not have any? That's reassuring...

Page 32 of this thread after the ziegler overhaul seized up.
Has anybody ever set the injection pump fuel and governor to spec? Wait... don't have yellow do it. They charged me $2400 chasing a worn thrust washer in the governor. Had to send it to my usual pump shop because it still didnt work, first place they look he said.
Ran great with no load they said. Ever see a cummins 855 with a 1710 or 2300 pump on it. Runs great with no load. Put some 2300 VTTA fuel settings to it and now you have a pulling engine, for 9.2 seconds.

What do we know? Nothing because there is no paper on the wall or big sign out front that says so.
 

Steve.ahlgren85

Senior Member
Joined
Jun 4, 2016
Messages
399
Location
Darwin, mn.
Are the pump and injectors original? Sorr I have missed alot of the thread.
I have seen a 3306t in a d7 have a injection pump isue and a day later spin a rod bearing. And a have personally seen a cat 966b toss a rod then have a rebuilt engine dropped in with the same pump and have the same cylinder lock up. That one was never solved and the machine is still sitting. Maybe they screwed up on the rocker arms. The owner gave us the machine but I haven't gotten around to hauling it. I've also witnessed a burnt cylinder in a old d7e 48a after a injector cup unscrewed and washed the cylinder during operation causing a piston failure.
Anyhow just tossing it out there not saying this is the cause but you never know.
The pump is original, Ziegler caterpillar replaced the Injectors with new ones.
 

kshansen

Senior Member
Joined
Mar 11, 2012
Messages
11,160
Location
Central New York, USA
Occupation
Retired Mechanic in Stone Quarry
I never could understand how a problem with a rocker arm getting too much or too little oil could cause a scored cylinder. Too little oil and rockers would wear out very bad and that would be obvious. Too much oil getting to the rocker assembly and the worst I can imagine is blowing oil out the breather tube, that too would seem to be very obvious.

Over fueling or pump timing off enough to cause fast cylinder failure I would think someone would notice smoke or strange sounds coming from engine even at no load.

Has anyone checked rack travel? If one or more pumps were installed wrong I could imagine that could cause a major problem.

Someone didn't cobble up injector lines and get firing order wrong did they. I know it sounds crazy but everything related to the engine does by now!

They didn't put direct injection pistons in a pre-chamber engine or the other way around did they?

We are not dealing with some exotic high performance engine like a Ferrari or a Formula One racer! Just a simple six cylinder two valve push rod engine!

Is the problem that there is no place to plug in Cat ET so no one at the dealer can work on it?
 

Steve.ahlgren85

Senior Member
Joined
Jun 4, 2016
Messages
399
Location
Darwin, mn.
The service manager said that they ran it for a good two hours, didn't notice anything wrong with the engine!!Do you think, like they are suggesting, that the fuel pump is NOT the right pump for a spacer plate block engine?I am fishing for answers to this machine.
 

Junkyard

Senior Member
Joined
Jun 5, 2016
Messages
3,636
Location
Claremore, OK
Occupation
Field Mechanic
They should know by arrangement numbers etc what is compatible or not. I don't buy it. The issues with that engine and their "diagnosis" as to cause don't inspire much confidence. As far as diesels go it doesn't get much easier than that engine. That could very well be their excuse now that they realize they failed in the due diligence dept when assessing your machine from the beginning.
 

Steve.ahlgren85

Senior Member
Joined
Jun 4, 2016
Messages
399
Location
Darwin, mn.
I never could understand how a problem with a rocker arm getting too much or too little oil could cause a scored cylinder. Too little oil and rockers would wear out very bad and that would be obvious. Too much oil getting to the rocker assembly and the worst I can imagine is blowing oil out the breather tube, that too would seem to be very obvious.

Over fueling or pump timing off enough to cause fast cylinder failure I would think someone would notice smoke or strange sounds coming from engine even at no load.

Has anyone checked rack travel? If one or more pumps were installed wrong I could imagine that could cause a major problem.

Someone didn't cobble up injector lines and get firing order wrong did they. I know it sounds crazy but everything related to the engine does by now!

They didn't put direct injection pistons in a pre-chamber engine or the other way around did they?

We are not dealing with some exotic high performance engine like a Ferrari or a Formula One racer! Just a simple six cylinder two valve push rod engine!

Is the problem that there is no place to plug in Cat ET so no one at the dealer can work on it?
I am going to check with them to see if they installed the direct injection pistons, that would be easy to check with the head off.He seemed to be suggesting overfueling as the possible cause. If they can't figure it out, then I don't know who can. I can't afford to have this keep happening without knowing, for sure, just what is causing the engine to fail. Thanks for your input.
 

Steve.ahlgren85

Senior Member
Joined
Jun 4, 2016
Messages
399
Location
Darwin, mn.
This machine was running great while I I stalled the skid plates, idling. Drove it over to the farm across the field, noticed that the engine was laboring, like trying to drive it with the brakes,both sides, applied.Noticed black smoke, not heavy black smoke, but was smoking. Engine actually shut off on the one mile across the field,twice. It started back up again, temperature was higher than normal, not in the red though. Probably should have called Ziegler right away, as they suggested, but I thought being a new engine, it was just part of the break in procedure. Any more suggestions are greatly appreciated. Thanks for your response.
 

d9gdon

Senior Member
Joined
Feb 12, 2010
Messages
1,517
Location
central texas
To me that is a classic sign of an out-of-time engine. If it were overfueling, it would take longer to gall the pistons and stall the engine. I would also think that you could smell diesel in the engine oil if it happened from overfueling that quickly. I can definitely see a problem with mismatched parts between direct inject and pre-combustion arrangements. They can pick up the phone and call Cat's technical department to have them research and identify any mismatched parts if they can't read a parts book. Just keep calling the service manager about it, he'll get tired of it after a while and get it fixed.
 
Last edited:

oldirt

Senior Member
Joined
Apr 22, 2009
Messages
504
Location
iowa
this just gets worse.. I am shocked that a cat dealership tech squad now apparently has so little real world diesel motor experience that they cannot get this thing squared away in about three days. (since the 3306 in this tractor has NO computer port to plug into and tell them what to do)
 

Steve.ahlgren85

Senior Member
Joined
Jun 4, 2016
Messages
399
Location
Darwin, mn.
I never could understand how a problem with a rocker arm getting too much or too little oil could cause a scored cylinder. Too little oil and rockers would wear out very bad and that would be obvious. Too much oil getting to the rocker assembly and the worst I can imagine is blowing oil out the breather tube, that too would seem to be very obvious.

Over fueling or pump timing off enough to cause fast cylinder failure I would think someone would notice smoke or strange sounds coming from engine even at no load.

Has anyone checked rack travel? If one or more pumps were installed wrong I could imagine that could cause a major problem.

Someone didn't cobble up injector lines and get firing order wrong did they. I know it sounds crazy but everything related to the engine does by now!

They didn't put direct injection pistons in a pre-chamber engine or the other way around did they?

We are not dealing with some exotic high performance engine like a Ferrari or a Formula One racer! Just a simple six cylinder two valve push rod engine!

Is the problem that there is no place to plug in Cat ET so no one at the dealer can work on it?
I called Ziegler caterpillar today and suggested that maybe they might have installed the wrong pistons, direct injection ports.The senior service manager had the day off today but,his replacement said that they were looking into that, he had no more knowledge on this machine.If they mistakenly put the wrong pistons in, would that cause the engine to fail so soon? I need to find the definitive cause of this engine failure. This makes the most sense to me.
 

Steve.ahlgren85

Senior Member
Joined
Jun 4, 2016
Messages
399
Location
Darwin, mn.
To give you guys an update on my machine. Ziegler called today and said that they are basically stumped on the cause of the engine failure. Service manager said they have to replace all of the parts they replaced the first time, new pistons, sleeves,main bearings and connecting rod bearings. He thinks that the fuel pump is delivering too much fuel into the cylinders washing the lubricating oil from cylinders, causing the failure. They plan to take off fuel pump and have it checked to see if it is up to specs.If they find no problem with it, he doesn't know what else to try.He wants me to bring the original pistons, which I still have, up along with the head from original engine to compare to what they have. I am hoping that the pistons won't match and that's the answer to the problem!
 

thepumpguysc

Senior Member
Joined
Mar 18, 2010
Messages
7,519
Location
Sunny South Carolina
Occupation
Master Inj.Pump rebuilder
How can you "rebuild" an engine & NOT get the inj. pump & injectors tested??
Arent they supposed to AT LEAST get it checked?? The injection system is the most important piece on the engine.!!! WOW..
Even when your getting your tonsils out they check your heart.. [simplest procedure]
The inj. system IS the heart of the motor..
Just something to think about..
 

Steve.ahlgren85

Senior Member
Joined
Jun 4, 2016
Messages
399
Location
Darwin, mn.
They said that they put all new injectors in and checked the engine for being in time. Other than that, I don't know what else to do with the machine, if the fuel pump is delivering fuel correct!
 
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