9 replies to this topic

[Gumboguy]

Gents:

 

Thank you for having me in your forum.

 

I purchased a 2000 JDM ej20tt from a Legacy GT and installed it in my 1974 VW Westfalia. Using the EMS Stinger 4424 and not the factory ems.

 

The twin turbo set up would not fit in the engine compartment, so I decided to use a t3/t4 hybrid that I had from a previous frankenmotor ej25. Headers look like they came out of a Baja bug, well, they did come out of a baja bug. The turbo sits right about at the alternator. This turbo appears to have come from an early 90's Nissan 300zx. Journal bearing. This turbo ran just fine and leakless on the prior ej25 turbo motor with the same EMS.

 

My turbo is now leaking oil at the turbine housing where the cartridge/bearing housing meets. Its a slow drip, but pesky. Drips on the pipes and smokes as well as smoke comes out of the tail pipe in blueish white and puffs of dark gray smoke on acceleration.

 

I have widened the oil return flange to a 5/8 with a 3/4 hose going to the oil pan in order to improve the oil drainage. I attached a clear hose to the drain just to watch what happens. It seems to drain just fine.

 

 

A: Crank case pressure? Whats it supposed to be? Am I getting blow by even though air bubbles make there way into the sump?

 

B: What is the stock oil pressure supposed to be hot at idle? at WOT?

 

C: Would it be so awful if I put the secondary vf27 on instead of the t3/t4? Do we really need the secondary turbo?

 

I'm not looking to race this old hippie bus, but I would like to keep up with traffic and head up hills without angry drivers piling up behind me.

 

I really need to get this project off and running.

 

Any help will be appreciated.

 

 

 

 

[duncanm]

Do you have the right banjo bolt restrictor hole in the oil feed side?

[Gumboguy]

Im not using the banjo bolts. This turbo didnt have them. I have a -3 AN 90 degree to 1/8 npt in the inlet. If I go to a vf27 stock turbo, I will be using the stock banjo bolts for oil feed as well as coolant.

 

Thanks for the swift reply.

[Gumboguy]

I have added a 1/32" restricter (a brass welding rod cut to 3/8" long and drilled to 1/32 fit inside the 90 at the oil inlet). This restriction has reduced the oil feed flow volume, but it still leaks out the piston ring (presumably). I say that because the drip forms at that part of the turbine housing. It seems no matter what I do to the oil in or the oil out, it still leaks.

 

I am temped to replace the t3/t4 turbo with one of the twin turbos that came with the motor stock. Would that be so bad? Lower end power with faster spool? But what happend when there is no secondary turbo to kick in?

 

Oh, thank you for the link to the Outback thread.

 

Please advise. :-)

[duncanm]

Presumably one small turbo will be just fine with a tune, obviously it'll drop off as RPM goes above 4k or so and you'll need to tune the wastegate to dump all that extra exhaust.

I think they're supposed to flow about 140hp each.

VF27 doesn'g have a wastegate, though - you'll need external.

[Gumboguy]

Thanks again. :-)

I arready have an external waste gate, so the vf27 looks attractive from a less hassle standpoint. I don't think I will mind the turbo maxin out around 4k. I don't intend play hardball with this motor. I recon a t4 compressor has more range?

I'm hung up on having the exhaust set up rewelded to accommodate the stock Subaru flanges only to find that I still get an oil leak in the replacement turbo because of something I failed to diagnose and catch with this current one. With so.many variables of Subaru flanges on turbos, It seems like I would easily set myself up for having the rarest set up to find a replacement for. Lol.

Thanks again. :-)

[duncanm]

btw - according to my FSM, oil pressures are 98kPa(14psi) @ 600rpm, 294kPa (43psi) @ 5000rpm

[Gumboguy]

btw - according to my FSM, oil pressures are 98kPa(14psi) @ 600rpm, 294kPa (43psi) @ 5000rpm

 

Thank you for the answer to the pressure.

 

hats really not good news for me. ;-)

 

!4psi is below OEM garrett turbo specs, No? How can that be that my oil pressure in a JDMej20 TT be som dang much higher than that? Its stock inside, stock injectors and fuel rail. The case has not been open.

 

What causes high oil pressure and what can be done to lower it?

 

Please advise.

[duncanm]

I'm guessing here, but there are two items to check.

 

1. oil pressure relief valve in pump - 85psi

2. oil filter bypass valve - 23psi.

 

btw - those numbers from the FSM. They're 'discharge pressure', and its not clear if that's engine or pump rpm. If you check the 'webs, typical oil pressure seems to be 15-30psi at idle (warm), and something above the relief pressure, 85-100 psi, at revs... someone else here with more experience should know.

[CodeBurn3r]

have you checked that the PCV is not clogged up?
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