It's settled. DIY hybrid turbo rebuilding time it is.

free5ty1e · Post by **free5ty1e** » Tue Jul 20, 2004 2:29 pm

Well, when taking apart my post-turbo intake section to score up the BOV piping's unnecessarily smooth exterior for the hoses/hose clamps to get a better grip on it... I discovered it was full of oil. So is my intercooler. And consequently, so is my combustion chamber at any given time on positive boost.

So, my stock turbo's blowing quite a bit of oil. So, it could use new seals anyway. So... I need to find me a t-bird turbo and rebuild kit, stat! I'm imagining that the oil entering the combustion chamber would dramatically decrease the effective octane of any fuel in the mix. I'm also imagining that the burned oil deposits will eventually increase the compression ratio by decreasing the actual size of the combustion chamber. I'm also imagining, more rather hoping, that once I get the Super Hybrid RHB5 turbo rebuilt with new bearings and seals and what not, that the burned oil deposits can be removed with a gas additive, maybe with combustion chamber cleaner to name something specific.

Anyone dealt with this before?

Brat4by4 · Post by **Brat4by4** » Tue Jul 20, 2004 2:55 pm

That's not your turbo blowing that oil. It's Oil blow-by from one of the hoses that comes off your engine and goes to the intake. You need an oil catch can on that line, not a turbo rebuild.

But if you do decide to go that route, I'd just send it all in to Deadbolt and have their expert eyes look it over, rebuild it, and have it ported or whatnot while it's there.

mTk · Post by **mTk** » Tue Jul 20, 2004 3:05 pm

It could be the turbo. Granted a lot of oil comes from blowby, but a lot more could come from the turbo itself.

MK

WRXdan · Post by **WRXdan** » Tue Jul 20, 2004 5:22 pm

The EJ22T I rebuild had little signs of oil in the combustion chambers. Only one cylinder showed signs but it was most likely a valve seal leaking. The motor has over 100K on it. But in general you will find oil in the intake tract due to blow by. I found oil in the IC of my WRX when it had 15K miles on it yet the plugs looked normal for a turbo engine.

free5ty1e · Post by **free5ty1e** » Tue Jul 20, 2004 10:13 pm

blow-by? Please 'splain. I fail to see the need for a line from the engine to the intake that blows oil. My stock turbo->TB pipe also was covered in oil, and there was no catch can in place stock. Why would they do this? Where would I put the catch can...? and...are you sure??

vrg3 · Post by **vrg3** » Tue Jul 20, 2004 10:29 pm

When you're on boost, crankcase fumes (which include vaporized and almost-vaporized motor oil) are sucked out of the crankcase by the partial vacuum at the compressor inlet. That coats the entire intake with oil.

The big discussion about how the PCV system works (and so where a catch can would go) is here: http://bbs.legacycentral.org/viewtopic.php?t=16496

free5ty1e · Post by **free5ty1e** » Tue Jul 20, 2004 11:53 pm

new rings = final solution to blowby, right?

vrg3 · Post by **vrg3** » Wed Jul 21, 2004 12:02 am

No, unfortunately. Even a 5000-mile old motor that was perfectly broken in does not have a perfect seal at the piston rings. Standard rings have gaps in them, remember?

It's possible that gapless rings would mostly eliminate blowby; I don't really know anything about them.

free5ty1e · Post by **free5ty1e** » Wed Jul 21, 2004 2:56 am

ah, crap. You're right. Forgot the gaps don't completely close when the piston's in place. Never heard of gapless rings, theres an idea. I suppose the catchcan (once we figure out where the hell to put one) would be the solution then

vrg3 · Post by **vrg3** » Wed Jul 21, 2004 4:14 am

I hadn't heard of gapless rings until ciper mentioned them in a post here once... I did a little Googling but didn't really learn much.

-K- · Post by **-K-** » Wed Jul 21, 2004 5:19 am

I think the rings are called Total Seal. I know they are recomended for turbos by the Ford 2.3 turbo guys I know. I think you can order them from summit or even autozone. My car gets some oil in the intake from the crank vents. The main reason they do that is for emmisions. And yes oil is bad for the octane but it should not be too much at a time, all the oil you see is built up from years.
I think the turbo hybrid is great, I love mine.

free5ty1e · Post by **free5ty1e** » Thu Jul 22, 2004 3:47 am

Well, all the oil I saw in the original turbo -> throttle body tubing may have been built up over the years... but when I took my intercooler/BOV assembly apart after less than a month of running it, I found quite a coating of oil in there. So it's significant in my case... compression test yielded no lower than 139psi, 155psi in the strongest cylinder... I'm just still assuming the turbo is blowing oil, on top of the blowby coming from the PCV system. So the rebuild would do me some good. It sure would be nice if we could figure out where a catchcan should go though

OR -- what if, hypothetically, we were to say "screw the emissions" and came up with an alternative to vent the majority of this all to the atmosphere, instead of our intakes... of course that would be even tougher than getting a catchcan in the right place

-K- · Post by **-K-** » Thu Jul 22, 2004 5:19 am

They will need a filter to keep stuff out of your engine. It will make a mess also. Catch can is the way to go if you want to mess with it.

free5ty1e · Post by **free5ty1e** » Sat Jul 24, 2004 1:16 am

OK, well for the catch can.... is there only one line from the PCV to the intake, or are there two? Either way... what kind of catch can do I need to look for? Vented? Sealed? I'm new to catch cans. And how will this affect the operation of the PCV system?

Anyone have a suggestion for an inexpensive catch can, and where I can get one?

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It's settled. DIY hybrid turbo rebuilding time it is.

Does your turbo blow oil?

It's settled. DIY hybrid turbo rebuilding time it is.