Friends....oil pressure dropped to 15#. Shutdown occurred but not before it took the turbo out. Nothing left the turbo but the shaft is now wobbly....bearing maybe? What would cause oil pressure to drop? Someone mentioned regulators?
The bypass and pressure regulator never give a problem,the pickup tube broke or a main bearing spun would be a good guess the oil pump very seldom fails
Are you sure the turbo didn't go 1st ?
They had the pan off, all looked good they said. Turbo could have gone first, I haven't heard full details. Thought I would take it for a spin here and see what you all thought.
could be the oil filter failed internally and caused the bypass valve to open
dumb question, but i'll ask it any ways ... was it low on oil ?
Quote from: eagle19952 on October 06, 2015, 08:32:05 PM
dumb question, but i'll ask it any ways ... was it low on oil ?
With them, that was my first question! It wasn't low.
Water pump was leaking into the oil so they are replacing that too.
Not sure on condition of oil filter.
The water pump won't leak water into the oil on a 92 series they have another problem
"They found a faulty seal in the water pump that was letting small drops of water into the oil".
" They " being the shop they were towed to.
was it a lot of water in the oil
Apparently not a lot of water.
I don't know about that shop the water pumps have a weep hole behind the housing in case a seal goes bad
look at the rod bearings. see if they are ok because bearings and coolant don't get along. but it takes more than an ounce or two of coolant to cause damage
I'll pass this along in the morning and see what's said.
I bet the blower and after cooler are a mess with all that turbo damage
They are pointing to DDEC, so they got another one to try.
A DDEC will not make any change in oil pressure. It may not read the correct pressure.
I'm hearing bits and pieces yet. Plenty of oil pressure but the DDEC wouldnt let it start...or crank.
Seems turbo was on its way out. Oil lined had some sort of blockage. DDEC had been giving them fits for a few days as well.
Up and running now, all seems right in the world. New turbo, water pump and a used DDEC. Road test tomorrow before they hit the road.
Things are a mess again. Stuck on the side of the road with no oil pressure...again. It was fine for 700 miles, 60psi then it shut them down at 20psi.
Everyone is stumped.
I would change OP sensor,if that didn't solve the problem then I would look at the oil cooler by pass valve.If the engine is equipped with a thermatic oil filter that could be a problem it dumping all the oil into the cooler and not the oil galleys when the oil temperature reaches 230 degrees.If he does have a thermatic control oil filter DD sales a kit to remove it he needs to toss it that wasn't a great idea
good luck
I passed this info on.....
If you have a oil pressure gauge in rear of the bus check that while you crank the engine. If you see pressure short across the pins on the oil pressure sender for the emc and the engine should start. You will have to unplug the sender in order to jump across the pins in the plug.
Jack
He should have a override someplace to override the DDEC
Quote from: blue_goose on October 11, 2015, 08:13:47 AM
If you have a oil pressure gauge in rear of the bus check that while you crank the engine. If you see pressure short across the pins on the oil pressure sender for the emc and the engine should start. You will have to unplug the sender in order to jump across the pins in the plug.
Jack
New gauges all the way around. They all say 20psi and well as the diagnostic had 20 as well [I think thats what he said]. They had bypassed DDEC but I'm afraid it didnt make any difference, still was 20psi.
They left the bus 4 hrs from home and will go with plan B tomorrow....whatever that may be.
Quote from: luvrbus on October 10, 2015, 08:16:55 PM
I would change OP sensor,if that didn't solve the problem then I would look at the oil cooler by pass valve.If the engine is equipped with a thermatic oil filter that could be a problem it dumping all the oil into the cooler and not the oil galleys when the oil temperature reaches 230 degrees.If he does have a thermatic control oil filter DD sales a kit to remove it he needs to toss it that wasn't a great idea
good luck
They changed the OP and checked the regulators. Going to do a quick oil sample while they figure out how to check the cooler bypass valve.
1 thing I forgot to mention if they break a oil bolt on the rocker arms it won't build up oil pressure it's rare but does happen
Thats interesting.
He is running up there today to do an oil sample, just to see what the past 600 miles did. In my mind if it were bearings the oil pressure wouldnt come and go like it has, it would be a constant, give or take a little when its cold.
I am sure they have pulled the valve covers if he has Jakes and checked for a solenoid that has came loose and blew out ?
They didnt pull this this go around but they do have Jakes. I will relay. Thanks!
Quote from: luvrbus on October 14, 2015, 07:55:59 AM
I am sure they have pulled the valve covers if he has Jakes and checked for a solenoid that has came loose and blew out ?
When I recently rebuilt my Jakes I found one of the little oil connection tubes was cracked in half. After I replaced it I gained at least 5 PSI cold and hot oil pressures. Even a small leak of oil can cause a noticeable drop in oil pressure. It's easy to check - with the valve covers off and the engine at slow idle (don't use fast idle, or you'll have oil splattering everywhere! Guess who found that out?), put 12V to each solenoid and look for leaks/squirts/dribbles at each connection tube and around each Jake housing.
John
?
Oil sample is complete, take a peek:
https://drive.google.com/file/d/0B5h5jkMRiXtvWkJzVmctSDBuaG8/view?usp=sharing
Copper in the oil anaylisis could indicate severe bearing wear from what I've heard.
Who checked the bearings and said everything was good the 1st time, that is a nasty sample 10% fuel and coolant in the oil will show a lot copper he does have problems now for sure
Guess no one checked the bearings, from what I am told. I pushed hard for them to get the oil sample done, glad they did. Notice there was only 650 miles on that oil.
He'll probably just pull it and drop in another used one. He got 6 yrs out of that one. :)