It aint over yet

 

Bill, so do you think the valves were your problem? any pictures of the seat wear?
Mike

 

i'm probably missing something here but how can you suck oil through the guides of turbocharged diesel?

 

Sooner or later you have to slow down. No the valves were not the problem. I changed the head and still have the knock that was being looked for. It made the engine run better, but fixed nothing. Lot of work and gaskets for nothing, engine has to come apart on the bottom.

 

If they didn't make sure the seats were centered, do you think they'd bother with checking the guide/valve stem clearances? I don't think so. Worn out guides let the valve stems move around and wear out any seals quick.
While leakage under boost conditions is unlikely, downhill runs would let oil past the guides.

We use bronze guide liners on 8500 rpm BBC but they don't run up many miles.

 

ROTFLMAO! I ain't starting no fight.

I'm just glad Haulin didn't get stuck in the Gulf Coast!

This waste oil thing has been beat to death!

 

fight? A nice easy going, passive old man, like myself?

 

It's the head in most ways. The gooey sludge on the valves is from the leaking compression/combustion getting up through the valve guides and reacting with engine oil. That's where the sludge is coming from.

The carbon that your seeing is the same thing, only in an area that oil couldn't get to. If there had been oil there, it would be REALLY bad.

Your use of waste oil is not a factor here. As you posted, the ratio is too small be really be significant at all.

Your larger turbine housing is, imo, a good thing, and probably has HELPED more than it HURT. The higher temps that the larger housing gives should burn off impurities better, and keep moisture under control. You're keeping EGT at reasonable limits, so I can't see any negative to the larger housing.


What's baffling to me is that the head swap didn't fix your problem! I suppose it's theoretically possible that the head caused some severe gunking problem and that an oil squirter got blocked or something, and this damaged a bearing or some other thing in the bottom.

It's sounds very much like the head is the real problem, but the short block you said makes a knocking sound.

Of course, maybe it *IS* all in your head!! LOL


jlh

 

Oh, and on the useless info front:

Cummins was contracted by Mopar to assemble the Hemi Crate engines for muscle cars (the 426, 472, and 528 Hemi big blocks), and a substantial number of these engines has VERY poor assembly work. I know a fella who has to sue to get his brand new 528 Hemi rebuilt by a reputable shop (Ray Barton, if you know who he is), because it came from the factory with horrible machining.


Maybe the same Cummins guy assembled your short block or head?

 

For me to say Ray Barton knows a little about Hemis would be my understatement of the year. Their Dart went fast at INDY. They also put weight in the car a coupla years back and set the SS/BA record at a 8.79 but some say John Armstrong can go that fast too in his L88.
There I go off topic again, sorry.

 

I lost a small piece of aluminum down the carb on my old '70 GMC gasser and it musta landed between the piston and the flat area of the cylinder head causing a slight interference and subsequent bottom end noise before dislodging and exiting the exhaust. Spark plug wire pulls found it to be the #2 cylinder and the motor got quiet with the plug wire pulled so I drove the 12 miles home with the motor quiet but missing. When I got home and reconnected the wire, the motor was some quieter but still had a slight knock. I pulled the front of the oil pan down and found I had just enough room to pull the #2 connecting rod cap. After pulling the cap, I found the journel smooth and shiney so I bought a single insert set and installed it after removing the old inserts. I siliconed the oil pan gasket surfaces and installed a new timing cover gasket and put everything else together. When I started it, the motor was quiet and stayed quiet for another 10 years except when the muffler would fall off every now and then. That was a good 'ol truck...for a gasser.
The point is hard carbon broken off could jamb things up and wipe a rod or even a main bearing. I hope the crank is ok and the job goes well.

 

Well if the piston grading complies,I have another crank here that is good. Hohn, thanks, sort of what I though of the carbon and as you said, goo. The head looks to me like a really bad job on the manufacturing end. Hope they did a better job onthe bottom. It is coming apart, should know something tonight.

 

Haven't been around much thru these problems you're having Haulin in Dixie, but if you can hear a knock over the rattle ,and injectors have been ruled out, it is the bottom end. Carbon inside combustion chamber has come from poor headwork in reman process. Don't think waste oil in that small amount is any issue either. Sounds like the head wasn't built right, and probably bottom end wasn't built properly either. Maybe you should change your name to MURPHY. Seriously though, we all feel for you, hopefully it won't cost you too much downtime and money.

 

Been reading about Haulin's engine issues for some time now. I really didn't think Cummins had Navistar-like assembly problems. Disappointed.

 

1 bad Cummins engine out of a million ain't too bad of a ratio. .