Hi

Earlier in the week by Favorit started leaking on the join between the exhaust manifold and the downpipe. I relpaced the gasket today, an tightened all the nuts as much as they would do up, but it is still leaking on the right side. :(

Should I have used assembly paste? As I just used the bare gasket, believing that it should compress to create a gas tight seal.

The car is fuel injection, so obviously I don't want to get any sealant on the lambda, but at the same point as the leak is pre lambda I guess that excess oxygen will be drawn in and give the lambda a false reading.

I have not checked to see if the manifold is cracked, because the heat shield bolts look very fragile, so I didn't want to remove them unneccessarily. Do these crack often?

Has anyone else experienced similar to this, and if so, how do you cure the problem?

Thanks;)

Drew

Check that ALL traces of the old gasket is removed.

Thanks Dave, will do. The downpipe was fine, but its hard to see the manifold side with the manifold bolted to the engine.

No probs, please let us know how it goes.

Time for an update. I finally got this sorted out. I coulld feel exhaust gasses escaping from the join between the manifold and the downpipe, so I assumed it was the gasket. I changed that, but there was still a leak, which was getting worse, and causing the car to run really bad, as the leak was before the lambda probe. Anyway, it turns put the downpipe was leaking on the weld where the flange joins the pipe. I fixed this over the weekend, and now the car is running fine. Thanks for the help again Dave.

:)Great news, any time.

glad you got it sorted. I think i had similar a while back and ended up replacing the bolts with non sleeved ones to allow the joint to be tightened up more.

glad you got it sorted. I think i had similar a while back and ended up replacing the bolts with non sleeved ones to allow the joint to be tightened up more.

can you let me know what bolts you used as i need to do mine and no idea where or what ones to get.

regards

Marcus

can you let me know what bolts you used as i need to do mine and no idea where or what ones to get.

regards

Marcus

There are four studs that hold the downpipe to the manifold and it's probably unwise to replace these. The nuts are also "special" alloy lock nuts which ideally are replaced every time they're removed, though it's not absolutely essential.

The two bolts that maintain the clamp from downpipe to catalytic converter with the springs look like 50mm M8 course threaded bolts and the shoulders are there probably to prevent overtightening which would transfer too much stress & vibration to the cat. If that joint is leaking, replace the gasket and springs before attempting to tighten it physically

There are four studs that hold the downpipe to the manifold and it's probably unwise to replace these. The nuts are also "special" alloy lock nuts which ideally are replaced every time they're removed, though it's not absolutely essential.

The two bolts that maintain the clamp from downpipe to catalytic converter with the springs look like 50mm M8 course threaded bolts and the shoulders are there probably to prevent overtightening which would transfer too much stress & vibration to the cat. If that joint is leaking, replace the gasket and springs before attempting to tighten it physically

mine leaking from right at the back of the engine, if i put my hand down there i can feel the gas escaping. Was going to put in a new gasket and see if that works. I might just replace it as ive done the rest of the exhaust exc cat.

mine leaking from right at the back of the engine, if i put my hand down there i can feel the gas escaping. Was going to put in a new gasket and see if that works. I might just replace it as ive done the rest of the exhaust exc cat.

Yes, could be the gasket or the manifold is cracked or the exhaust gas analysis pipe is broken.

The... clamp from downpipe to catalytic converter with the springs... are there probably to prevent overtightening which would transfer too much stress & vibration to the cat...

^^ :thumbdwn: The cat is integral with the manifold on the 1.6 & that doesn't have to be isolated from vibration etc...