Piston lost a chunk? Some of the older versions on the pistons were susceptable to fatigue and could loose part of the top of the piston, sometimes with a dramatic shower of hot debris if the engine had a straight pipe instead of a muffler.
On the other hand, lots of them slobber a mixture of unburned diesel and carbon (looks like motor oil) when they are not working hard and are not up to proper temperature.
In this case, with a sudden onset after a known "event", I would start by idling the engine and loosening each injector line in turn. Hold a rag over it to knock down the fuel spray, but listen to the engine to see if each one affects the sound and rpm of the engine equally. This may point to a specific cylinder as the problem. You are looking for the ones that don't affect the idle much or at all. You can also get some good info by "shooting" each exhaust manifold runner with an infrared thermometer after working the engine a little while, looking for a cool one.
Once you ID the problems, then I would start by checking injectors or swapping from a good cylinder to a bad one and from the bad one to the good one to determine if the problem stays with the cylinder or moves with the injector. Problems that stay with a certain cylinder include injection pump problems as well as piston and piston, ring and sleeve problems. It might be possible to remove the precombustion chamber and put a scope into the cylinder and examine the top of the piston.
Another quick diagnostic step is to remove the exhaust manifold and examine the inside of the ports for oil etc.
CCJersey, Thanks for the tips on diagnosis. I will pass on to owner and see what he finds out. Not sure on hrs of this machine or how hard it has been operated in the past. Jim.
Hey Jim,
I can not comment on noises that someone heard, or if it is effecting the motor, but I have a D6-9u that will slobber along with some other bigger Cats I own too. On my 9u, if it is let to idle for an extended period or run at low rpm's, it slobbers oil out of the stack. When this happens, I simply run it hard working at full throttle and the slobbering stops.-glen
Our channel highlights machines from the earliest Holt and Best track-type tractors, equipment from the start of Caterpillar in 1925, up to units built in the mid-1960s.
Chapter Fifteen
| Placerville, CAChapter Two
| Stradsett, Nr Downham Market. Norfolk PE33 9HA UKChapter Two
| Faulkner Farm, West Drove, Wisbech, Cambridgeshire, PE14 7DP, UK
Antique Caterpillar
Machinery Owners Club
1115 Madison St NE # 1117
Salem, OR 97301
Terms & Privacy
Website developed by
AdCo
"I also joined a year ago. had been on here a couple of times as a non-member and found the info very helpful so I got a one year subscription (not very expensive at all) to try it out. I really like all the resources on here so I just got a three year. I think its a very small price for what you can get out of this site."
-Jason N