Builds 1985 JDM 3B Engine Rebuild and Other Stories (1 Viewer)

mongoose2231

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Hey Onur, are you able to revert to NA for the time being?
When I did my home brew turbo, I thought of that, although I do have a flipped over exhaust manifold which would make it easy. I even kept the stock exhaust down pipe.
Not sure what else to suggest bud.
Bummer..
Edit:
I did notice you mentioned wanting to use the guted turbo as a simple air intake but since it is busted...
 
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Onur

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Hey Onur, are you able to revert to NA for the time being?
When I did my home brew turbo, I thought of that, although I do have a flipped over exhaust manifold which would make it easy. I even kept the stock exhaust down pipe.
Not sure what else to suggest bud.
Bummer..
Not an option...

I’m taking the Expo As Fawk Prius.
 

Onur

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I’m almost positive I have a crankcase pressurization issue....

I forgot to post up that I had oil blasting out the exhaust and making puddles....

391C244D-DA39-4055-B3BD-F5590697EFDC.jpeg
 

Onur

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Just weird. How much oil pressure would it take to blow turbo that quick?
A lot. I have an oil pressure gauge but haven’t tested yet.

Cold oil psi can be pretty high I’m sure.

But once warm, factory specs are about 5-8psi at idle and 30-80psi at WOT.
 
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This is a messy thing you can try that I almost did, but stopped when I figured out my problem with the catch can.. Take off your oil filler cap and ensure you have blowby coming out and see how much. Provided you have blowby coming out then certainly passageways from crankcase to valve cover are clear. Cover the oil filler with some type of rag so it doesn't make too much of a mess, but run it that way to see if the oil leakage in the turbo stops. If oil leakage in the turbo stops then pressurization is your issue and you need to check the size and stoppage of your valve cover vent tube. The diameter of the valvecover vent tube in my 3B is 5/8" approx. Using a smaller hose, or kinked hose to vent the exhaust will cause pressure buildup.

If you vent in between the air filter and turbo on the "air filter housing neck" you will have a slight vacum to help scavenge the crankcase(turbo providing suction and filter providing resistance with your vent between). If you pipe it into the neck the turbo should suck in the oil mist blowby and burn it through the engine. Or put a catch can with significant flow between.

Theoretically it takes some time for your rings to seat after a rebuild, and you should experience more blowby during this time.


All that said if your turbo bearing is worn allowing contact between turbine and housing then it's going to seap oil out.
 

mongoose2231

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Oil out the exhaust means it is making its way into the cylinders. You had that sucker rebuilt, so it can only enter via intake. That may mean that indeed your crank case is overpressurizing as I assume you have routed your valve cover breather into the intake preturbo. I blew my rear main due to overpressure before adding a catch can. The hose I had rerouted from the valve cover to the intake kinked under heat, so was easy to spot problem.
 

AussieHJCruza

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Oil out the exhaust means it is making its way into the cylinders. You had that sucker rebuilt, so it can only enter via intake. That may mean that indeed your crank case is overpressurizing as I assume you have routed your valve cover breather into the intake preturbo. I blew my rear main due to overpressure before adding a catch can. The hose I had rerouted from the valve cover to the intake kinked under heat, so was easy to spot problem.
It must be coming from the turbo tho, because looking at the earlier pic of the exhaust manifold, it's dry so it can't be coming 'through' the engine as such
 
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When the shop install the new linner, did they honed them or slide a piston ring to check for possible deformation? Not sure, maybe small imperfection between wall and ring can wear and get proper seated. The brake issue may have happen in the worst timing and created enough blow by to cause turbo drain to not work properly. Just thinking...
 

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