Tubular Manifold Exhaust Leak Issues

I was at a track day this past Saturday and the car was running great through 95% of the first 30 minute session out on the track. We were getting near the end of the 30 minute session when the car went into limp mode and since we were right by pit lane we pulled off.

When we got back to the pits my friend popped the hood to let the heat escape and that's when we discovered there was an exhaust leak forming between the cylinder head and the tubular manifold. It wasn't all that bad, so I figured we could continue run the car for the remaining sessions, but it only got worse, so we decided to call it a day.

This is now the 2nd time that this has happened to me, so I'm looking for suggestions on how to fix my leaking exhaust manifold/cylinder head issue so that the 3rd times the charm and the exhaust manifold/cylinder head don't leak ever again.

1st time there was an exhaust leak:


If it helps here are my engine mods:
Engine:
- BHW block bored to 81.5mm
- Mahle Pistons
- PD 150 ARL crank
- Rosten rods
- PD 150 ARL head, ported and flowbenched
- BEW injectors with FIRAD +120% nozzles.
- GTB 2260VK turbo
- S3 intercooler, PD 150 euro radiator carrier.
- Darkside Developments hard-pipe kit
- Stage 3 Colt cam.
- Cryogenic treatment of all engine parts by 300 Below
- Custom headstuds by Matt Whitbread

Thanks in advance for any help.

You told me on email that you dont run a gasket between the head and manifold, there is your problem and now your manifold is warped and needs removing.

I also said you need to check downstream in case something is touching

Not sure why you needed to post about something we discussed 2 days ago?

No sure why you have no gasket tbh.However, I have seen this issue a number of times on customers cars.

You tighten them up and few months down the road they come out again.
But in my case they were always the bolts and not the studs (and nut).


I would recommend studs and avoid bolts.


In the end I found once the head was off (for other work) fitting a cut down stud fixed it.

ryanp said:

You told me on email that you dont run a gasket between the head and manifold, there is your problem and now your manifold is warped and needs removing.

I also said you need to check downstream in case something is touching

Not sure why you needed to post about something we discussed 2 days ago?

Click to expand...

I never said there wasn't a gasket installed currently...because there is a gasket installed. What I did ask is if I should run a gasket after I skim the manifold and check everything else, since I've heard of people not running an exhaust manifold gasket.

I appreciate the advice Ryan and the only reason I started this thread is that I've got 3 people offering 3 different ways to install the exhaust manifold after it's skimmed.

Bobby Singh said:

No sure why you have no gasket tbh.However, I have seen this issue a number of times on customers cars.

You tighten them up and few months down the road they come out again.
But in my case they were always the bolts and not the studs (and nut).


I would recommend studs and avoid bolts.


In the end I found once the head was off (for other work) fitting a cut down stud fixed it.

Click to expand...

Here's a picture showing current configuration of the exhaust manifold. If you look closely you can see the exhaust gasket poking out just a tiny bit.


I'm currently running studs and even installed Stage 8 hardware that you can see in the picture. I'm even considering installing Nordlocks to double up on preventing an exhaust leak in the future.

Thanks for the advice. ??

3L3M3NT said:

I never said there wasn't a gasket installed currently...because there is a gasket installed. What I did ask is if I should run a gasket after I skim the manifold and check everything else, since I've heard of people not running an exhaust manifold gasket.
I appreciate the advice Ryan and the only reason I started this thread is that I've got 3 people offering 3 different ways to install the exhaust manifold after it's skimmed.
Here's a picture showing current configuration of the exhaust manifold. If you look closely you can see the exhaust gasket poking out just a tiny bit.

I'm currently running studs and even installed Stage 8 hardware that you can see in the picture. I'm even considering installing Nordlocks to double up on preventing an exhaust leak in the future.
Thanks for the advice. ??

Click to expand...

Are these the single gaskets?
If so it is usually better to use the thinner metal gasket which cover all 4 exhaust ports
Like this one https://www.ecstuning.com/b-elring-parts/exhaust-manifold-gasket/037253039d~elr/

mk3pd said:

Are these the single gaskets?
If so it is usually better to use the thinner metal gasket which cover all 4 exhaust ports
Like this one https://www.ecstuning.com/b-elring-parts/exhaust-manifold-gasket/037253039d~elr/

Click to expand...

Yeah it definitely isn't a metal gasket that's currently installed. I let the shop that was working on the car order the replacement gaskets, so that was clearly a mistake to let them order the exhaust manifold gasket.

This time I'm having someone local working on the car, so that will make it easier for me to keep tabs on how things are going, since it can be these little things that can make all the difference in the end.

Thanks for the advice ?

Just to follow up on this thread... we found out that there was a slight twist to the exhaust manifold flange that goes against the head, so I took to an engine builder/machine shop that was able to machine it flat again.

We also discovered that it wasn't the flange against the head that was leaking, but the connection between the turbo and exhaust manifold. Either the bolts loosened up enough to start the exhaust leak or the gasket gave out and that's what made it seem like the bolts had loosened up.
Either way the turbo was rocking back and forth on the manifold and it even caused the driveshaft to ever so slightly rub on the downpipe, but luckily didn't do any major damage and the only way you could see it was happening is there's now a small shiny spot on the downpipe.

After I get my exhaust manifold back from ceramic coating, we're gonna start re-assembling everything and one thing I'm not sure is a good idea or not, so I figured I'd see what you guys thought.

I'm wondering if it would be a good idea to use high temp red Loctite to prevent the nuts from backing off on either the exhaust manifold or the bolts/nuts the connect the turbo to the manifold?
This is what I ordered --->High Temp Red Loctite

I have installed a few of these manifolds (not DS) and no issues after 2 years.
Always use studs + metal gasket.

mk3pd said:

Are these the single gaskets?
If so it is usually better to use the thinner metal gasket which cover all 4 exhaust ports
Like this one https://www.ecstuning.com/b-elring-parts/exhaust-manifold-gasket/037253039d~elr/

Click to expand...

hm, I've seen these on gasoline 8V cars but never thought to use them on diesels
Nice bit of info. MLS gaskets are magical stuff

tube headers are a pain in the arse for this reason. They are super cool, but can be a pain in the long run.

Macradiators.com said:

I have installed a few of these manifolds (not DS) and no issues after 2 years.
Always use studs + metal gasket.

Click to expand...

I was using studs, but the 1st shop that had my car and removed my turbo and manifold didn't check to make sure the flange was straight, so I'm sure that was part of the issue. Plus as you saw in the pictures, they used a fiber gasket for in between the manifold and cylinder head and as we found out after the turbo was removed that they also used a fiber gasket there too.

Lesson learned there, order the replacement parts that the shop will be using to install on your car as much as possible and bring your car to a trusted shop in your area to work on your car.

[486] said:

hm, I've seen these on gasoline 8V cars but never thought to use them on diesels
Nice bit of info. MLS gaskets are magical stuff

Click to expand...

I wish I had known to use MLS gaskets last year when my exhaust manifold was leaking and creating a mess in my engine way and all over the underside of the hood.

vtpsd said:

tube headers are a pain in the arse for this reason. They are super cool, but can be a pain in the long run.

Click to expand...

Being that I bought the car 2nd hand I didn't really think much of it when I bought the car with a tubular manifold, so its been a bit of a learning curve on making sure everything seals properly.
If I could have been the one ordering the tubular manifold and turbo for my car, I would have gone with the BMW style turbo and corresponding tubular manifold that has a V-Band connection for mounting the turbo to the manifold in a superior way to the 3 bolts that are required for the Audi style connection. IMO

Like so.






Otherwise this setup is the way to go for anyone upgrading the turbo on their MKIV car.




Already with an exhaust pattern for a VNT-17, so you don't have to change your exhaust setup to accommodate a different turbo.


Anyway thanks to everyone that helped me figure out the best gaskets to run with my turbo setup.


Should I put a dab of Hi-temp Loctite on each exhaust stud before a nut goes on just to play it safe?

I wouldn't Loctite the nuts. Antisieze maybe though unless you are using copper nuts.
Loctite would be good for the studs where they tread into the head.

3L3M3NT said:

Should I put a dab of Hi-temp Loctite on each exhaust stud before a nut goes on just to play it safe?

Click to expand...

they get hot enough that it won't matter.

as flee said, just use it in the cylinder head to keep the studs in place
use the normal self-locking nuts and thick stainless washers as VW did

that's an interesting looking (gtb?) manifold casting. Far too classy for me, but nice nonetheless.

flee said:

I wouldn't Loctite the nuts. Antisieze maybe though unless you are using copper nuts.
Loctite would be good for the studs where they tread into the head.

Click to expand...

That makes sense. The studs are already in the head and haven't backed out the 2 times the nuts were removed, so I think those are good.

[486] said:

they get hot enough that it won't matter.

as flee said, just use it in the cylinder head to keep the studs in place
use the normal self-locking nuts and thick stainless washers as VW did

that's an interesting looking (gtb?) manifold casting. Far too classy for me, but nice nonetheless.

Click to expand...

I decided to go with the stage 8 locking hardware and will be installing Nord-Locks as well.

Yep, those are GTB cast manifolds. You can get them at 2 place to my knowledge.
https://www.facebook.com/ZTurboZwettl/posts/2214903738591815

And at Pioneering Performance that's a vendor on here.
http://forums.tdiclub.com/showthread.php?t=493912

Zturbo.at https://www.facebook.com/ZTurboZwett...14903738591815 company is where @majesty78 works. I bet you can find more info from him.

Link is not working Razvan...

now it does

https://www.facebook.com/ZTurboZwettl/