I've rebuilt the Hitachi HT18 turbo twice, the turbo oil input line/fitting is not leaking and yet I am getting oil seeping between the turbo and the exhaust manifold.
Where is the oil most likely to be coming from, turbo or engine? The engine was rebuilt and has about 8 hours running time on it.

 

Run the engine without the turbocharger attached. It will be loud, but it may answer your question.

Remember to block off the oil/coolant.

 

any thrust play in the turbo?

i assume the smoke is coming out of the tailpipe and not just burning off of the manifold?

 

How would I go about running it without the turbo? You mean, take the insides out of the CHRA, put it back together and then cap the oil feed line? Or is there a more simpler method?

 

Yes, a small amount is coming from the area of the turbo but I can't tell exactly where it is coming from.

 

Had the same leaking on a rebuilt stock turbo - a BNR stage 1.

Added a restrictor to the oil feed and no more leaking between the cartridge and turbine housing.

 

BNR is a little different since he removes the restrictor plate which is inside the turbos to make sure they get plenty of oil, clamping oil flow though is up to you on the hybrids but i assume not the case here.

did you replace the carbon seal on the main shaft near the turbine wheel? that is the main culprit for oil leaking where you described if it is coming from inside the turbo. could also simply be coming off the oil drain line if it isn't sealed very well. if the tailpipe isn't smoking like a train then it isn't the engine.

 

Don't do this:

https://www.rx7club.com/single-turbo...-turbo-793269/

 

I did replace the carbon seal. Somebody else mentioned that maybe I didn't clean the carbon deposits under the seal good enough so I took it back apart and re-cleaned the shaft.
A little bit of smoke comes from the area of the turbo but 95% comes from the tail pipe.

 

I find it hard to believe that the engine might be spewing oil since it was rebuilt just a few hours ago BUT as SPOCK once said, "Once you eliminate the impossible, whatever remains, however impossible, must be true."

 

What do you guys think about........ take the turbo back off, take out the guts of the CHRA including the shaft and wheels and all seals, put it back together and put it back on. Then block of the oil and water lines. Would the CHRA itself be damaged doing this?

Something simpler?

How about, just remove the turbo and attached the AFM to the other side of the FMIC tubing.

 

This is funny.

 

i would just yank the turbo off and inspect the manifold. oil in the manifold pre-turbine wheel= engine oil seal issue. oil only past the turbine wheel= faulty turbo.

 

OK, thanks. I'll give it a try.

 

I pulled the turbo and there did not appear to be any oil in the manifold but I wasn't totally sure so I capped off the oil and water lines. I have a FMIC so it was pretty easy to attach the AFM also.
Fired it up and............. YEA..............NO SMOKE. So, the smoke has to be coming from the turbo.
But where? I sent the backing plate to GPopshop and they pressed in the one piece seal in, so that should be OK.

 

I bought this turbo last month on here. I was told that it had very low mileage on it and was in perfect working order. I paid $165 for it.

 

^ It's funny that you mention the seller claiming that it is a "low mileage" turbo... I love how everyone trying to sell a turbo claims that it has "low mileage".

Hmm... All of these 13BT's with 100k+ miles on them, yet the turbos have only 30k miles!?

The turbo I have is a "low mileage" turbo. I wonder why I hear a ticking noise. Heh' - It works, though.

 

I think it was supposed to be imported from japan or something..... yea, right. I think this guy replaced his smoking turbo and then sold it to me.

 

doesn't sound like a turbo coldside issue but it is a hotside issue, mainly the carbon seal or the restrictor inside the CHRA was removed somewhere along the line allowing the turbo to see full line pressure and pushing oil out the back end.

the carbon seal may have cracked during assembly, it is rather brittle.

careful when cleaning the bore for the carbon seal, if too much material is removed it will allow the ring to expand and then will not seal properly.

 

We replaced all of seals. We used a kit from GPopshop. GPopshop pressed in the one piece seal. These parts are new: Journal Bearings, Piston Ring for Turbine End, Thrust Bearing, Thrust Collar, Seal Ring for Bearing Housing, Thrust Spring for Backing Plate and the Thrust Spacer.

Does the thrust spring install facing up or facing down? I don't know what else to look for.

 

i understand but without tearing it back apart you can't see what the possible issue is. i would focus on inspecting the turbine main shaft, the piston ring(carbon seal) and the CHRA end where the piston seats into for any pitting or wear.

you may have even gotten a faulty piston ring or one out of spec.

 

OK, thanks, I'll tear it back down. I'll pay more attention to the areas you mentioned. Hopefully the problem will become apparent.

 

I took it apart again. I didn't see anything wrong so I had a couple of guys check it out. They didn't see any thing suspicious but there is a problem with the hot side because the heat shield was covered in oil. Maybe I could swap in the shaft from the original turbo but then it would need balanced again. Or maybe I should just buy another one and hope somebody else doesn't sell me their burned up junk turbo.

Advice/ideas??

 

Will an S4 turbo work on an s5?