Can oil supply to stock twins be blocked?
 

i want to troubleshoto to make sure its the turbos smoking. is the oil to the turbos just teed from the main lines or is it the end of the line for the oil? in other words..can i block off the oil to the turbos without blocking the entire oil supply. thanks

diagram looks like its just teed off so nevermind ...

Yes, simply unbolt the compression fitting under the air pump, clamp on a piece of hose to the feed line coming from the block, and route it back into the oil filler neck securely. IF your twins are sequential, you'll need to lock the front turbo from spinning to prevent bearing damage. DO this by using a pair of vise grips carefully clamped onto the compressor nut, and perhaps use tape or zipties to attatch the vise grips to something nearby so that the whole deal doesnt spin.

If you are nonsequential you can probably let the car idle without either turbo spinning at all, but if you plan to do much revving up then you'd want to secure both the turbos as described above.

I have done this procedure to troubleshoot smoking twins before. You generally have to let the engine warm up fully to burn off any remaining oil in the turbos, then shut it off overnight and start it again the next day to truly see the result.

I was going to say, do NOT start the car and let the turbos spin (even at idle speed) without oil going to them. You'll need to physically prevent them from spinning to prevent damage to them. Also like stated about you'll need to probably let the car warm up for a bit and burn off any excess oil/dirt/grime and the wait for it to cool before starting it back to to diagnose the issue... but DO NOT deprive the turbos of oil if they are spinning!

well the turbos are junk so i couldnt care if they got fucked up from being without oil.

Then why even bother testing them, just unbolt the whole damn thing and bolt on something else.

You'll be able to tell if the engine was burning extra oil because the exhaust ports would be full of carbon instead of the brown/tannish color with black around the fringes.

because i want to drive the car. iv had this new motor for months and barely been able to driv eit. i want to break in the motor so i can sell the car. when the motors broken in i'll put on a set of non-burning turbos to sell it with but for now i dont care theres no point for them to be there since i cant boost it. im almost tempted to clip out the exhaust fins just so if it did lock up it wouldnt restrict the exhaust. then again i have a feeling that would affect backpressure..so i might just leave em

Take them off and then remove the center sections from the turbine housings. Cut out a piece of metal to bolt back into the turbine housings. Block off the oil drain tubes with plates, and block off the oil feed using a standard bolt in the top of the front iron. Bolt the turbine housings back on the car and you can go with no danger of screwing anything up. You'll need to engineer an air filter for the intake tube, you dont want to be sucking air through the intercooler.

BTW the car will run like shit above 4krpm without air from the turbos, because the car will go rich. The turbos move air even when not in boost, you know.

If it were me, I'd just drive it with the smoke and top off the oil frequently until the engine is broken in. You could also try a restrictor pellet in the oil feed banjo bolt.

yea i was thinking about that, restricting the oil so it would atleast get sOME oil during moderate driving to keep the parts lubricated enough. how would i go about with this? could i just get a copper crush washer with a smaller I.D.?

You'd want to get something put into the banjo bolt. It'd be kinda hard to do, and probably not worth the trouble. It's much easier when you have an aluminum fitting or flange on the turbo inlet, you can simply find a pill slightly wider than the ID of the fitting, drill halfway down into the fitting so that the pill will slide in and come to a stop without going all the way through. Then just put your line back on top and you're done.

I have used the metal vacuum/boost pills from the FD twins as oil restrictors before :rofl:

lol. perhaps i'll flip the oil inlet pipe thats bolted to the turbos backwars so the fitting is facing the fenderwall, then keep the hose attached to the motor side pipe like it is now and put a pill in the hose and then attach it to the turbo inlet pipe. maybe? i could keep the pill fro mmoving in the hose by putting a hose clamp on th elocating where it sits..should work i guess

I wouldnt want to drive around with a piece of hose for oil supply line. The FD can see over 100psi of oil pressure at as much as 250*F. Only SS braided line is made for that application, and it's not very flexible to be trying to rig onto the compression fittings that the metal rails use.

i still dont get how to restrict oil flow using a pill in the banjo bolt without it potentially clogging something for good, let alone making it able to get back out easily. using oversized washers like I stated before makes no sense I realize...duh...if you could give me a more detailed way of using a pill let me know

It doesnt matter where, in the turbos oil supply, you put the restrictor.

The supply comes from the port on the front iron, where the banjo bolt clamps down onto the metal tube. The tube goes behind the alternator, and joins into the Y pipe that feeds both turbos.

You can put the restrictor anywhere between the banjo bolt and the turbo center section inlet. Since the metal pipes are really thin, there's no way you can put a restrictor in them. So you choose one of the banjo bolts. Since you have 1 bolt on the engine side and 2 bolts on the turbos, the logical choice is the one bolt.

The restrictor just blocks off most oil flow but has a 0.060 or so hole in it to let oil pass. This keeps excess pressure from building up in the turbo center sections, but still provides just enough lube for the turbos to operate.