2.0 T exhaust manifold cracks

[DamirGTI 365]

Took a few hours to port/clean up one of the manifolds .. and as it appeares every single one of them has internal cracks , in the same areas around the corners on the outlet side to the turbo . 

 

I've 4 of them and they're all cracked .

So obviously picked the one which was the best .

 

There's some nasty steps on the inlet and outlet sides od the manifold , so I cleared those off , hopefully it'll do some quicker spool up time trick .. but yeah it is a crap design .

 

Anyhow , I wonder if it would be good idea to drill small holes on the ends of the cracks , or it might be best to leave it as is ?! 

Edited October 25 by DamirGTI

[DamirGTI 365]

... one of the others , with the cracks spreading little bit further and wider on the inside and up/outside towards the turbo ring seal at the back : 

Edited Sunday at 07:51 PM by DamirGTI

[petert 641]

Interesting. I'll have to look at the one I have here. I suspect it's a common problem, as someone asked me recently if I'd sell mine.

[DamirGTI 365]

Yeah, not sure what happens at those two corners that makes them crack .

The outer webbing is fairly thick, and neither of the cracks goes all the way through to the outside , only on the inside surface .

They don't look too deep, so been thinking about either grinding them out completely  down to the bottom of the cracks , or just drilling small holes at each end of the cracks to stop them from spreading further .

I wouldn't really fancy trying to weld them . If I had a TIG welder, then maybe , but I haven't had much luck welding cast iron manifolds with a stick welder and nickel rods.

Even with the whole posh procedure of preheating and slow cooling , they still split after a while .
The worst thing would be if a chunk of weld cracked off and trashed the turbo .

[SRDT 255]

Same cracks on multiple maniflods that means that the design is flawed in some way. Maybe it's the shape, maybe it's a recurring casting problem or maybe the material isn't the right one for those exhaust temp (won't help is the engine isn't stock).

 

Anyway you are unlikely to do a long lasting repair on a cast iron crack that is there because of a design flaw.

 

Are the turbos hot ends also cracked?

[DamirGTI 365]

True , seems like there's very few of these engines which haven't been messed up with the boost pressure . 

 

A lot of them where converted to LPG too , especially here in the East .

Two which i taken apart i know for sure where on LPG , other two not sure . 

 

Nope ! , all the hot ends on the lot of turbos which i have are good , no cracks . 

But i've seen those crack as well on TCT's .

[wicked 107 3 Cars]

On 10/25/2026 at 7:24 PM, DamirGTI said:

Took a few hours to port/clean up one of the manifolds .. and as it appeares every single one of them has internal cracks , in the same areas around the corners on the outlet side to the turbo . 

 

I've 4 of them and they're all cracked .

So obviously picked the one which was the best .

 

There's some nasty steps on the inlet and outlet sides od the manifold , so I cleared those off , hopefully it'll do some quicker spool up time trick .. but yeah it is a crap design .

 

Anyhow , I wonder if it would be good idea to drill small holes on the ends of the cracks , or it might be best to leave it as is ?! 

 

 

 

 

This is one the hotest spots of the manifold on boost, so I think it is a material issue. Don't see how forces from the turbo would make it crack here.

As long as it holds boost, I would not do anything about it.  

[DamirGTI 365]

Righto !

I made just an small shallow hole on the end of that crack , and rounded the edges of it , so it might do something to stop the crack from spreading or non at all .. will see .