Downpipe flange leak

[SalvadorP]

Thanks Steve

Well. I won't be able to really fix it for a while. In Barcelona I live in an apartment and don't have a place to work at, let alone do a job of this magnitude. I hope it holds up another year or so. Also having a weird deceleration noise, which is worrying me more than the leak right now. But that's another issue.

It's gonna be a fun drive. 1200km. Our cars are so freaking amazing to drive. It's a pleasure.
Hope you find time to do it soon. And good luck.

Cheers,
Salvador

[classicswede]

Originally Posted by Rversteeg

Although normally a gasket is not used, a gasket used for eg the 850 can be fitted. OEM art. no. 8642450

That gasket can be added between the turbo and manifold not the downpipe. No gasket is needed in either location

[Rversteeg]

You are correct, my mistake, I misread the question.
It is my experience though that the nuts of the downpipe connection need retensioning every now and then.

[TonyS9]

Originally Posted by SalvadorP

Oh, that makes more sense. Because the gasket has 4 holes. And the flange has 3 bolts.

Anyway, in my car there is indeed a gasket between the turbo and the manifold, maybe one of these mentioned above, and it's leaking. I can't find that gasket locally. I'm considering just covering the gap with putty.

Its not unusual for the manifold-turbo joint to leak a little, especially when cold and especially when you don't have a gasket (neither of my B230FTs do). It should not make much noise normally. If its really bad you may need to resurface the manifold or the turbo, which might mean removing the studs on the manifold.

Getting all the nuts tight on the joint is also a bit of chore and tricky, so check them first.

[SalvadorP]

Update: It seems that mechanic was right, the smoke was just dw40 burning off. Today with cold engine it didn't smoke much if at all. Neither is it smoking with the engine hot. So i guess for now the exhaust putty did work and the turbo to manifold connection seems to not be leaking.

My car does leak a bit between turbo and manifold enough to make soap bubble and it has a gasket, probably the 850 one, put in in 2019, 40k km ago. So i guess it will probably hold on for a while.

We also discovered a leak right after cat, we didn't put putty because the car was already hot.

[SalvadorP]

Pic of the cat leak and another leak on the resonator (that's the resonator right? Before the muffler?) that I'm embarrassed to have missed until now. What the hell. It's a huge crack.

[SalvadorP]

Originally Posted by TonyS9

Its not unusual for the manifold-turbo joint to leak a little, especially when cold and especially when you don't have a gasket (neither of my B230FTs do). It should not make much noise normally. If its really bad you may need to resurface the manifold or the turbo, which might mean removing the studs on the manifold.

Getting all the nuts tight on the joint is also a bit of chore and tricky, so check them first.

Yes, it's a bit of a nightmare to tighten those. Especially the bottom ones. Even worst with the add pressure and fear of breaking one of the studs!

Btw, out of curiosity. I've read about not using SS studs on the aluminium head, what about the alloy head is that alright? Or original studs are a must? I'm not doing that job now, for sure. But for future reference.

[TonyS9]

Originally Posted by SalvadorP

Yes, it's a bit of a nightmare to tighten those. Especially the bottom ones. Even worst with the add pressure and fear of breaking one of the studs!

Btw, out of curiosity. I've read about not using SS studs on the aluminium head, what about the alloy head is that alright? Or original studs are a must? I'm not doing that job now, for sure. But for future reference.

I don't understand the question on the alloy head, its Alminium Alloy.

Mild steel is the best choice, it will be alot stronger than stainless.

Stainless will corrode less because its less reactive, but also its equipotential is closer to Aluminium. However corrosion is slow on these. I've never changed or snapped any on a red block. I have tried stainless metal locking (aviation) nuts, they seem ok.

[SalvadorP]

Originally Posted by TonyS9

I don't understand the question on the alloy head, its Alminium Alloy.

Mild steel is the best choice, it will be alot stronger than stainless.

Stainless will corrode less because its less reactive, but also its equipotential is closer to Aluminium. However corrosion is slow on these. I've never changed or snapped any on a red block. I have tried stainless metal locking (aviation) nuts, they seem ok.

I'm dumb. I thought alloy was different from aluminium. So the 16v head is the exact same material? Before I bought my car someone on us Volvo forums told me I should stay away from the GLE 16v because of the aluminium head.

So, it's not absolutely necessary to change them everytime you mess with them? But i guess you should at least have spares just in case. I thought i read it was advisable to change them because they are probe to snapping.

[griston64]

Originally Posted by SalvadorP

I'm dumb. I thought alloy was different from aluminium. So the 16v head is the exact same material? Before I bought my car someone on us Volvo forums told me I should stay away from the GLE 16v because of the aluminium head.

So, it's not absolutely necessary to change them everytime you mess with them? But i guess you should at least have spares just in case. I thought i read it was advisable to change them because they are probe to snapping.

Both the 8v and 16v heads are Aluminium. The only reason to avoid the 16v is it's an interference engine so if the belt snaps the valves have a nasty meeting with the pistons