My D5C started using oil about fifty hours after engine rebuild.About a quart an hour under hard use.Oil pressure is 70/75 engine has no blow by and runs perfect.Pulled the turbo and found oil in the compressor side,took it to the shop for a rebuild($500) still going through oil.Today I serviced engine and pulled the hose from the compressor to the intake manifold, oil in hose.Left hose off and started engine,half throttle cold oil,and it's dripping a drop of oil every ten seconds out of the compressor.Is there supposed to be any kind of restrictor in the oil feed line? The drain seems open.Or did I just get a bunk rebuild.
Bad turbo there should be no oli going through the turbo
Before you condemn the turbo, check the drain line for obstructions.
And inspect all of your air intake, I just helped a customer avoid the hydrostat pump set rebuild they said they needed because of lack of track power, which turned out to be a totally pancake plugged air filter. Sometimes I just don't understand.
He said drain was open
he said it 'seems' open. i personally would remove the complete drain tube and check the opening back into the block. sometimes, the drain gets capped or plugged after turbo removal to keep debris from getting in and then overlooked upon reassembly. been there . or if there is a short piece of hose in the drain tube assembly, check to see if it is swelled internally causing restriction
Exactly my thoughts. Straight after an engine rebuild there's a distinct possibility of a notorious blue cap being left in there somewhere.
Talked with the turbo guy today,He asked about the possibility of "upstream" oil entering the turbo from inlet side.There is no crankcase breather or other source of oil other than the oil feed 70psi going to the turbo.The crankcase vents out of the valve cover at the rear of the engine goes overboard at the skid plate.engine has 0 detectable blow by.Turbo guy says that under "normal circumstances" a turbo does not Even need a seal. As the oil enters the turbo @ 60/70 psi it goes to the shaft that has a hole in it that meters how much oil it can pass through,what oil does come through drops to a catch cavity where the drain tube should be more than able to drain it back to the crankcase. He suspects an obstruction in the return.Im going to pull the return line put a new piece of hose on it and give it a blow job in the next couple days.He did say some engines have a tube inside the crankcase that can loosen and turn causing the oil to return under the static oil level causing back pressure in the drain.
If there is zero flow detectable from the breather tube, it would be worthwhile seeing if the breather is clean. You should at least be able to to detect a slight "pumping".
My observation was at the front oil fill on the tap pet cover,when I said no detectable blow by, there is a slight pulse,but no more coming out than going in.Right now I'm leaning towards the return circuit.
UPDATE! Problem solved.Today I pulled the oil in,and oil out,lines from the turbo,both clean and no obstruction.By the way the banjo bolt on the oil in,is orficed to control volume.Put a hose on the return fitting in the block,clear as well.Started it,to warm up.Was going to pull the hose from the turbo out,to the intake manifold. When I noticed that the hose from the air filter to the turbo in side was collapsed!! Shut it down and opened the air filter housing,pulled both filters and both were clean.Got a light and looked into the housing and way in the back stuck into the outlet tube was a hand towel.At the time of the engine rebuild someone Had wiped out the housing and lost or left a towel.The super high vacuum on the intake side was literally sucking the oil through the turbo.Im sure glad I diden't bitch at the turbo guy.But instead took his advice and was going to eliminate all other possibilities before condemning my turbo,or his work!