50 trim owners: check your compressor housing!!

[oldman]

Alright, before the last two posts (before Paul) are taken too far and mis-interpreted by newbies. Yes, leaking through the center section into your crankcase during a static pressure test has long been a known issue, it is nothing new, if you're just finding this out now, you have not read any of the boost leak test threads within the last 2 years. This however, doesn't mean the compressor cover leak is no big deal because the two have nothing to do with each other, any boost leak is a big deal and should be addressed, especially when the solution is as simple as a layer of RTV.

 

[BoostedTalonTS]

Alright, before the last two posts (before Paul) are taken too far and mis-interpreted by newbies. Yes, leaking through the center section into your crankcase during a static pressure test has long been a known issue, it is nothing new, if you're just finding this out now, you have not read any of the boost leak test threads within the last 2 years. This however, doesn't mean the compressor cover leak is no big deal because the two have nothing to do with each other, any boost leak is a big deal and should be addressed, especially when the solution is as simple as a layer of RTV.

It is true: I haven't ready any boost leak threads in the past two years... Having run only Mitsu center sections in the past, I have never HAD to go scourer the boost leak threads for possible solutions. -That is, until I got this 50 trim six months ago. For the record, it wasn't leaking back then on the old setup.

...As you said yourself, a boost leak IS a big deal. I DO NOT like the fact that I am relying on oil pressure to seat the shaft seal. -Who knows what is actually going on while under boost plus add in the fact that the shaft is also spinning. Dunno... that just strikes me as odd. I guess I should have done more homework before jumping into a 50 trim.

 

[oldman]

...As you said yourself, a boost leak IS a big deal. I DO NOT like the fact that I am relying on oil pressure to seat the shaft seal. -Who knows what is actually going on while under boost plus add in the fact that the shaft is also spinning. Dunno... that just strikes me as odd. I guess I should have done more homework before jumping into a 50 trim.

This issue isn't just limited to a 50 trim, all CHRA's does it. Why? Because the so call "turbo seal" really isn't a seal in the sense of what we normally think a seal is, it is simply a piece of metal plate pressed up against the housing via oil pressure. The only way the "seal" can be damaged is through excessive shaft play, move the leak tester to the LICP and move on, after checking for shaft play and making sure the compressor cover is sealed against the back plate of course. Remember, the turbo seal isn't the only place for pressure to enter the crankcase during a static pressure test, it is the other places that you need to worry about, not the turbo seal as long as you don't have excessive shaft play.

http://www.dsmtuners.com/forums/showthread.php?t=169435 Read what I added in #8 in post #2.

 

[BoostedTalonTS]

Hmmm I could appreciate this perspective if the situations weren't so drastically different... in the past, on my old 20g I was able to boost test up until 20psi with out problems (although I was doing the test while the engine was warm, and at TDC. -not the 30* ATDC as you recommended in th eother post). On this 50trim, I can't get this thing to hold anything over 5psi! -to me, that is cause for concern... with only about 200 miles on the 50 trim, it held to 10-12psi without any audible bubbling noises coming from the oil pan... now with ~1k on it, it is clearly audible.

Question Oldman: If this 50 trim has a leaking center section, what good would it be to attempt to see if the compressor cover is leaking, given the low pressure that the center section can't even seemingly hold no more then 5psi? -I have already presure tested the complete FMIC (from the lower pipe --> TB... no leaks... BTW, didn't you sell me those TB shaft seals some time ago?).

 

[oldman]

in the past, on my old 20g I was able to boost test up until 20psi with out problems.

I have tested many many cars with different turbos, T25, 14B, 16G's, 50trim, GT-R's...etc., the results are always the same, gurgling sound in the crankcase. Disassemble a turbo and take a look at the so call seal so you know what I'm talking about.

(although I was doing the test while the engine was warm, and at TDC. -not the 30* ATDC as you recommended in th eother post)

I don't see how that is possible since TDC = valve overlap unless your compressor regulator is set to 50+psi to overcome the overlap. I have tested this theory multiple times on different cars and the results are always pressure out of the tail pipe.

On this 50trim, I can't get this thing to hold anything over 5psi! -to me, that is cause for concern... with only about 200 miles on the 50 trim, it held to 10-12psi without any audible bubbling noises coming from the oil pan... now with ~1k on it, it is clearly audible. Question Oldman: If this 50 trim has a leaking center section, what good would it be to attempt to see if the compressor cover is leaking, given the low pressure that the center section can't even seemingly hold no more then 5psi? -I have already presure tested the complete FMIC (from the lower pipe --> TB... no leaks...

You're making some assumptions here, how do you know no leaks has developed between 200 miles to 1k? You're assuming the change came strictly from the CHRA, let's not forget that pre-intercooler, compressor cover and the 90* coupler/elbow to LICP as well as the coupler to intercooler are often suspects. Like I already said, RTV your compressor cover and test your system from the beginning of the LICP. I will assume that you have logging capability without looking at your profile since you're running a 50 trim, if you truly are losing that much air through your CHRA during operation, you should be able to pick up signs through logging.

If your compressor cover doesn't have an o-ring and you didn't seal it with RTV, it is guaranteed to leak without having to test anything. The point of this thread is that the cover must be sealed either by an o-ring or RTV.

BTW, didn't you sell me those TB shaft seals some time ago?).

I don't remember but it's certainly possible.

 

[BoostedTalonTS]

...You're making some assumptions here, how do you know no leaks has developed between 200 miles to 1k? You're assuming the change came strictly from the CHRA, let's not forget that pre-intercooler, compressor cover and the 90* coupler/elbow to LICP as well as the coupler to intercooler are often suspects. Like I already said, RTV your compressor cover and test your system from the beginning of the LICP. I will assume that you have logging capability without looking at your profile since you're running a 50 trim, if you truly are losing that much air through your CHRA during operation, you should be able to pick up signs through logging.

Actually, I didn't ASSume anything... I boost TESTED everything back when I had it for ~200 miles, then AGAIN, just lastnight (~1000 miles)... The REASON I suspected a boost leak was BEACUSE of my tuning/logging conditions with fuel trims being all over the place.... Since then, I have been maticulously checking and re-checking for boost leaks. -Please don't confuse my inexperience with the 50trims to mean that I'm some noob here.
I realize that my specific issue is OT, so I'll end it here.

...I don't remember but it's certainly possible.

It was you: Positive Feedback was left back in 7/05.... what's up Oldman? -memory isn't what it used to be, eh?

 

[oldman]

fuel trims being all over the place

It would be pretty hard pressed to blame the CHRA for inconsistent fuel trims.

It was you: Positive Feedback was left back in 7/05.... what's up Oldman? -memory isn't what it used to be, eh?

7/05......I can't even remember who....I mean what I did last night.

 

[BoostedTalonTS]

It would be pretty hard pressed to blame the CHRA for inconsistent fuel trims.

Well you know what I mean... I can usually keep the fuel trims around 100-110% on my existing setup (haven't got the Link installed yet, so I'm still using the Stage 3 Keydiver's EPROM + SAFC w/ MMCD )... It seems like after making a base adjustment one day, the next they would be like 15-25% difference under the same driving/load conditions... I've already ironed out it being a fuel pressure and/or fuel delivery problem, wideband shows that it's running a tat bit on the lean side, bun into boost, I'm around a 12.5 with minimal knock. Currently I'm only running off of the WGA so that limits the 50 trim to about 10psi -still breaking in the 2.4L .
I know this is kinda OT, but it still pertains to 50 trims leaking, I guess... In my case, I can actually hear a difference in when the turbo boost is built above 5psi while driving... it still pulls up until 10psi, but it has a totally different sound to it... For the sake of this thread, I will double check my compressor cover this weekend and verify that it's not leaking.

7/05......I can't even remember who....I mean what I did last night.

NICE!!!!

 

[Jst4Cyl]

Is this leaking more common in the older CHRA or is this just something that is somewhat a defect from the get go? I just got my 5031 (PTE) not to long ago and finally got around to getting it on so I hope I don't run into this also. Thanks guys

 

[blcknspo0ln]

It's not particularly a defect, just the nature of mating metal on metal. If you look at my past pictures, you'll notice that my PTE turbo came with a red Oring around the entire housing. Whether or not that was enough to stop leaks, i'll never know, since I RTV'd it anyway. Other 50 trims like my old SBR G50, did not come with that Oring. Besides, ensuring you don't have this problem takes one wrench, 15 minutes, and a tube of RTV. Why NOT do it?

 

[94Jettameowpsst]

Its funny i see this thread. I did a boost leak on my car and for some reason i heard a hissing sound basically at my turbo but could never figure out where it was coming from?!?

NOW i know haha

 

[fwdeclipse]

Just checked a buddies G50 and it is leaking massively from this area. I knew we should have just done it before we installed it.

 

[blcknspo0ln]

Is this a new G50 or an older one? I'm curious to know because I know SBR supplies their own housings and I'd like to know if they are putting the Oring around the compressor housing.

 

[fwdeclipse]

Its a new one. He just bought it maybe a month ago. The first leak test I did for him it was not leaking. His car would hardly boost at all after a couple of weeks. I threw the tester back on it and it wont even build 5psi, it just leaks right out.

 

[JusMX141]

The last two G50's I rebuild did not have o-rings beneath the covers.

Some T04B rebuild kits come with a very thin paper gasket to be used between the compressor cover and backing plate, but this gasket will not work with turbos using an "E" or "S" cover.

 

[blcknspo0ln]

Its a new one. He just bought it maybe a month ago. The first leak test I did for him it was not leaking. His car would hardly boost at all after a couple of weeks. I threw the tester back on it and it wont even build 5psi, it just leaks right out.

That sucks. Did you pull it off and fix 'er up?

The last two G50's I rebuild did not have o-rings beneath the covers.

Some T04B rebuild kits come with a very thin paper gasket to be used between the compressor cover and backing plate, but this gasket will not work with turbos using an "E" or "S" cover.

Are you also using any type of sealant on these rebuilds? Are they leaking after the rebuild?

I just pulled my compressor cover off and the RTV I initially put in there definitely created a nice seal since it took a little convincing to remove from the backplate. I just cleaned up the edges with a buff wheel and still plan on putting RTV in there. It takes 2 minutes, doesn't harm anything, and provides peace of mind.

 

[JusMX141]

My rebuilds with a "B" cover get the thin paper gasket, and I use a thin bead of Ultra Gray Permatex around the lip of the sealing surface of the "E" and "S" cover Garretts.

 

[Artago]

Hi all. I have been directed to this thread by Tom (blcknspo0ln) because I recently (2 hours ago) did a boost leak test and discovered a leak in the compressor housing on my T04B V-Trim. This turbo is brand new and ran for less than 200 km. I'll be pulling it off the car tomorrow and sealing up the leak.

Anyways, I just wanted to say "Hello" and join this thread. I'll post my progress with some pics here later when I seal the compressor housing leak.

Thanks,

Tom

 

[DSM90AWD]

My factory new GT3582R leaked a bit at the back plate as well.
RTV for the win