SR20's SUCK, recurring leak

[towlie]

Okay so, I've had my s13 blacktop SR for about 5 months with most of them being problem free daily driving. Recently I thought I had developed a nasty exhaust leak by scraping a hole in the down pipe when I noticed a terrible lawnmower sound.

Surprised to not find a massive gaping hole in the DP (only dented) I popped the hood and found the problem, scraping the downpipe must have blown out the turbo to manifold seal, I could feel exhaust leaking out.

I retired the car from dd duties and yanked the turbo out. The turbo to manifold gasket was so had I could wiggle the turbo with my hands and there was literally only half a gasket remaining.

Replaced/installed:

Complete OEM t25 gasket kit
S15 multi-layer manifold gasket
PBM cobra downpipe to prevent future scraping
Aftermarket turbo manifold
FRSport AN turbo line kit
CS BMC heat shield

The t25 had no shaft play and everything was cleaned/inspected before re-installation.

Stoked I hadnt broken anything removing it, everything was installed and I fired it, only to find the annoying fart sound still remains and it still leaks in the same place.

WTF?!

Could the t25 be blown even with no shaft play? Did I forget to replace anything? Maybe over/under tightened a bolt somewhere (no torque wrench everything was tightened till it could tightened no more)? I'm totally stumped, any help would be awesome!

[doomviillain]

If there's no smoke im pretty sure the turbo isn't blown. The torque specs when bolting the turbo on to the manifold is 27-35 ft-lbs I think (Someone correct me if I'm wrong). Try re-torquing the bolts or worst case, upgrade to a better gasket.

[towlie]

There was several wisps of smoke upon initial start up but I assumed it was oil that leaked out when I changed out the lines.

I'll remove it and re torque, also what gasket is considered better than oem?

[!Zar!]

Sure everything is tight?

[towlie]

Yup totally sure, I took my time to ensure everything was secure. I'm going to remove the assembly and install FRSport copper locking nuts, and re torque. Should I replace the manifold studs? I used the ones off my stock unit, perhaps they stretched? Also I can re-use the manifold gasket or replace that aswell?

Thanks all

[Sileighty_85]

Originally Posted by towlie

.
I'll remove it and re torque, also what gasket is considered better than oem?

I love this gasket using it on 2 of my SR's and a few customers Never had an Issue

Mr Gasket Exhaust Manifold Gasket - Nissan SR20DET - Enjuku Racing Parts, LLC

[!Zar!]

s15 7-layer gasket is all that is needed.

Fuck all that other noise.

[doomviillain]

I would say a multi layer gasket from frsports.

edit: zar beat me to it

[SLiDe_WaYz]

Did u dent your oil pan and that noise is coming from the pickup sittin on the bottom of the pan? Happened to me just ask sleighty up there he heard it lol

[codyace]

Originally Posted by !Zar!

s15 7-layer gasket is all that is needed.

Fuck all that other noise.

OEM B15, better yet, third of the cost. Heck if you need more layers you can buy 2 OEM B15 ones and be better off.

Edit: B15 SR20 are 3 layer MLS like the S15 ones (which are 6 or 7 layer)...

[codyace]

And in regard to the thread, it's not potentially leaking from the turbine housing to CHRA flange is it?

[towlie]

I've already installed a new oem multi layer manifold gasket.

Originally Posted by SLiDe_WaYz

Did u dent your oil pan and that noise is coming from the pickup sittin on the bottom of the pan? Happened to me just ask sleighty up there he heard it lol

Nope, looks straight.

Originally Posted by codyace

And in regard to the thread, it's not potentially leaking from the turbine housing to CHRA flange is it?

Im fairly certain it isn't, if I put my hand between the turbo and car I can feel exhaust being pushed out of where the manifold to exhaust gasket is..

I'm thinking I didn't tighten something enough. Heres my plan:

Remove assembly, remove studs (on exhaust manifold) tighten with loc-tite. Install with copper lock nuts and I'll look around for another gasket option (mani to turbo) ...but first I need to find motivation lol :|

Thoughts?

[codyace]

The turbo to manifold gasket can be purhcased at your local Nissan dealer, same gasket as used on the TT-Z cars. You can also get new OEM hardware and locplate when you order that gasket too to ensure a good seal. Those copper lock nuts work too, but I like new OEM hardware with those plates.

Loctite isn't going to do much in that area, it's way beyond the heat range to work.

[e1_griego]

You sure that turbo manifold isn't cracked or something? Since it's an ebay tubular t2.

Try your stock manifold...

[benarovi]

you NEED the locking tabs for the mani to turbo, get the copper bolts, use loctite on all the bolts, tighten as hard as possible, bend the tab correctly, and put back on the car see how it does. get s.s turbo lines if you dont already, makes taking all that off much easier
use the oem gasket on fr sport for the turbo-mani

[anarchyperf]

As benarovi said, make sure you put the locking tabs on or you will become very familiar with tightening the nuts and replacing the studs.

[towlie]

Originally Posted by codyace

The turbo to manifold gasket can be purhcased at your local Nissan dealer, same gasket as used on the TT-Z cars. You can also get new OEM hardware and locplate when you order that gasket too to ensure a good seal. Those copper lock nuts work too, but I like new OEM hardware with those plates.

Loctite isn't going to do much in that area, it's way beyond the heat range to work.

That's what I figured about the loctite, but I don't think it will hurt lol. Found an oem multi layer flange gasket at FRSport I'll add aswell.

Is there a specific way to bend the locking tabs? I used a flat head and rubber hammer, it sure didn't look pretty lol

Originally Posted by e1_griego

You sure that turbo manifold isn't cracked or something? Since it's an ebay tubular t2.

Try your stock manifold...

I got it from huffandpuff00, it looks legit to me. But I'll put the stock back on

Originally Posted by benarovi

you NEED the locking tabs for the mani to turbo, get the copper bolts, use loctite on all the bolts, tighten as hard as possible, bend the tab correctly, and put back on the car see how it does. get s.s turbo lines if you dont already, makes taking all that off much easier
use the oem gasket on fr sport for the turbo-mani

Got it.

[Sileighty_85]

wait so, your using the S15 gasket on an AM manifold?

is the Port flange a one piece design?

If so thats your problem. You cant use a S15 MLG with a one piece flange cuz of the rivets used to hold the MLG together are keeping the flange from sealing properly

[codyace]

Originally Posted by towlie

Is there a specific way to bend the locking tabs? I used a flat head and rubber hammer, it sure didn't look pretty lol

Yea it's not going to look pretty at all, I used a screw driver and a hammer much like you..the key is to get a good solid crease in the tab to keep in place.

I've had the OEM 300zx Turbo hardware on all of the stuff I've done, and NEVER had a leak there....figure that stuff is designed from the OE to last for quite some time.

I'm not a big believer in those copper nuts either, just because of the fact that the OE stuff works so well. Not saying they dont work, I just don't like spending money on aftermarket stuff when OEM Nissan works so well.



I got it from huffandpuff00, it looks legit to me. But I'll put the stock back on



Got it.[/QUOTE]

[arg23]

I kept burning out gaskets, and having the turbo come loose from the manifold during our races, losing all boost as hot exhaust gases exited pre-turbo. A little further investigation found a great deal of scale buildup, or rough surface from the gasket material "bonding" with the turbo flange.

I think under high stress and heat, the gasket changed properties and created an ultra hard carbon deposit on the flange. I kept putting fresh gaskets in but the surface was not flat and the new gasket would soon fail in exactly the same manner.

Inspect your gasket mating surfaces for uneven finish, I surfaced ours and the problem has been resolved since. Additionally get new studs, they stretch out over time and loose some of their tensile strength, they wont stretch and hold during heat cycles. And maybe dont use cheap gaskets sent with the cheap kits, I really like the OEM style, they seem a lot more durable.

We dont bother with the locking tabs on the race cars, we tried to be very diligent with them when we went through a half dozen gaskets, they didnt help. I use them on my street cars however.

And I have always kinda liked Cody's stance, stock cast manifold is pretty badass. We arent using it anymore on our race car, but it doesnt see the same kind of stress the street cars do. If I had a badass extrude honed, and external wastegate stocky like Cody though... I would be rockin that.

[towlie]

I ALWAYS use OEM gaskets, no matter the application. Also as previously mentioned im going to return to stock manifold

Just purchased several items from FRSport including this:

Nissan 4 Bolt Turbo Turbine Inlet Gasket T25 T28 SR20DET 4 Layer Type

I'll update accordingly, thanks for the advice

-Zach

[!Zar!]

Fuck lock tabs.

I purchased a stamped stainless steel gasket from ATP turbo, tightened the fuck out of the nuts, and welded the nuts down. Never have had any sort of leaks since.

[mikerbike]

Oh dang. I should get rid of my SR before it develops a leak. I didn't know this was such a common and terrible problem.

I don't run a turbo-manifold gasket on my KA. It's only been that way for about a month of daily driving.

My SR has (what I assume is) the original gasket with a factory manifold. I've reinstalled it twice. If I need to remove the turbo again any time soon, I'm leaving the gasket off.

[anthonyr sil8ty]

Originally Posted by mikerbike

Oh dang. I should get rid of my SR before it develops a leak. I didn't know this was such a common and terrible problem.

I don't run a turbo-manifold gasket on my KA. It's only been that way for about a month of daily driving.

My SR has (what I assume is) the original gasket with a factory manifold. I've reinstalled it twice. If I need to remove the turbo again any time soon, I'm leaving the gasket off.

do you realize how dumb you sound?

anywho OP, I had the same issue when I was bottom mount, I was running a aftermarket downpipe, test pipe, and cat-back. I didnt have the flex jont anywhere in the system so all the vibrations etc put all the strain on the oem nuts and studs. I doubled nut'd and used lock tite on the studs which seemed to work the best.

[!Zar!]

A lot of diesel truck guys, as well as dsm guys run their turbo without a gasket.

Just make sure both flanges are straight, and smear a little wheel bearing grease on the flanges and tighten it down.

But if you do the way I suggested, you won't have to worry about exhaust leaks.

WELD THE NUTS.

[anthonyr sil8ty]

Originally Posted by !Zar!

A lot of diesel truck guys, as well as dsm guys run their turbo without a gasket.

Just make sure both flanges are straight, and smear a little wheel bearing grease on the flanges and tighten it down.

But if you do the way I suggested, you won't have to worry about exhaust leaks.

WELD THE NUTS.

dsm guys dont use studs and nuts like nissan's, they have bolts that run throught the manfiold and into the exhaust housing. i would imagine the dsm turbo flange bolts being alot stronger then 8mm studs. SPOT WELD THE NUTS i will agree with.

[codyace]

Originally Posted by !Zar!

A lot of diesel truck guys, as well as dsm guys run their turbo without a gasket.

Just make sure both flanges are straight, and smear a little wheel bearing grease on the flanges and tighten it down.

FWIW: Real Diesel guys (not those bro dozers) run OEM gaskets


Well, even I can't deny the fact that doing this will work...I guess in the grand scheme of things I can say if you're pulling the turbo you're taking the manifold off anyway, so it's not like it's anymore work for removal LOL.

....although I think I'd use Copper RTV before grease, but I guess the end result is the same, burnt crud to help seal it up haha.

Originally Posted by !Zar!

Fuck lock tabs.

They're still the second best option. Consider them the condoms of the world, with welding being abstinence.

[fliprayzin240sx]

You sure the flanges are not warped? Also, like already stated, since its an aftermaket manifold and you fucked the DP up from bottoming out...are you sure the manifold isnt cracked to hell? I'm willing to bet the manifold is cracked on the collector before anything else...

[e1_griego]

^Yup, exactly.

[mikerbike]

Originally Posted by anthonyr sil8ty

do you realize how dumb you sound?

Internet sarcasm getting the best of you again?

But really, SR20s SUCK because the some exhaust gasket goes bad all the time on every SR20 ever made. Put your SR20 in the garbage.