smoke from manifold

[fla 9]

When the engine is ticking over the exhaust mani tends to start leaking exhaust fumes, appears to be from the head side rather than the downpipes. I'e just replaced the gasket. I ti tightened the bolts just in case, bit this hasnt solved it. Still leaking and is accompoanied by a whistling/hissing noise (as though the gasket is leaking). Can i use anything to create a better seal? Difficult to actually pinpoint the exact source of the leak though.

[red-rado 0]

Did you thoroughly clean the mating surfaces up before replacing the gasket?

Could the manifold be cracked?

[boost monkey 0]

ditto possible cracked manifold.

[Kevin Bacon 5]

Those metal VW gaskets take a bit crushing to get a good seal, how tight did you tighten the nuts?

 

Ditto on the cracking too. My manifold for cyls 1, 2 and 3 had a big crack in it which stank of fumes as it was warming up, but sealed shut when hot. It throws the lambda out so needs to be sorted.

[fla 9]

Will have a look this afternoon. Yes i cleaned up the surfaces although i didnt tighten one of the studs properly in the head so it spins when you tighten the nut further. Hope the manifold isnt cracked tho, that would really cheese me off.

Need to do the suspension today though and at least connect the driveshafts so the car can move...

[fla 9]

Ok its not exhaust smoke (from the smell) - which is worrying as i cant loacte where its coming from. Its seems to be something on the surface, from the back of the block. Smells a bit strange, not sure if it's oil, or what. Dont know what to look for...Seems to still come when the engine is off, so obviously not an internal leak.

[pete_griff 0]

it's quite normal for there to be the odd bit of smoke/strange smells etc if you have done a head gasket change - all the new gaskets bedding in with the heat etc - it's just if the burning continues that you have to worry about it...

 

just give it a thorough check all around the exhaust to make sure nothing is touching etc (that's presuming it doesn't have a leak or the manifold isn't cracked...)

 

if it is, then all being well i will have a good set of manifolds/downpipes available come the end of september if you can wait that long...

[fla 9]

Cheers Griff, will do - i've removed the manifold heat shield for the moment just to try and pinpoint the source of the smoke as the engine warms up, but not had much luck. I'm just afraid of it ALL going up in smoke. Might give the back of the block a good blast with compressed air just in case ther is any accumulated rubbish that could be burning on any flat areas.

[fla 9]

as it does not appear to be exhaust smoke, more likely oil or some othe gunge on the mani or block, is there anything i can spray on and rinse off or use compressed air to remove, rather like an engine degreaser? Dont want to use the latter as it might attack delicate components that are not quite visibile from above.

[boost monkey 0]

so it doesn't smell like exhaust fumes? Yeah more than likely some oil left on the manifol when man handling it.

 

My 16v swap in the golf did this, I crapped it for a couple of days and then it just stopped. Turned out to just be some gunk when I was moving the exhaust about and eventually burnt off.

 

You could leave the car running with the bonnet open for a while, that would at least get some airflow to remove the smoke. You might wanna get a torch down there though and make sure there isn't a big blob of gunge else it'll be smoking for ages.

[Album56 0]

Are you sure there is no oil leaking from rocker cover? My G60 has occasional stink especially when hot & it looks like rocker cover gasket leaking at back & occasional oil drip onto exaust manifold causes smoke/stink for a few minutes. Mines going to have new gasket next week, hope that fixes it.

Mick

[boost monkey 0]

Surely A G60 rocker would leak onto the inlet manifold first, and then overflow onto the exhaust manifold.

 

In which case, you'd probably want to get it fixed soonish.

[fla 9]

Took it for a short run yesterday. Its not driven daily yet, so this doesnt help. After oil temps were reached i gave it a good blast, came back and the smoke was there again from the downpipes. Is there any way, short of removing the downpipes and cleaning them on the surface, to get rid of the supposed offending deposits? Its just a bit worrying and dont want totake it anywhere until i'm happy that it wont just catch fire?

[pete_griff 0]

Took it for a short run yesterday. Its not driven daily yet, so this doesnt help. After oil temps were reached i gave it a good blast, came back and the smoke was there again from the downpipes. Is there any way, short of removing the downpipes and cleaning them on the surface, to get rid of the supposed offending deposits? Its just a bit worrying and dont want totake it anywhere until i'm happy that it wont just catch fire?

 

you'll be fine - you just need to drive it much harder to really make sure you've burned all the crap off! :twisted:

[fla 9]

Took it for a short run yesterday. Its not driven daily yet, so this doesnt help. After oil temps were reached i gave it a good blast, came back and the smoke was there again from the downpipes. Is there any way, short of removing the downpipes and cleaning them on the surface, to get rid of the supposed offending deposits? Its just a bit worrying and dont want totake it anywhere until i'm happy that it wont just catch fire?

 

you'll be fine - you just need to drive it much harder to really make sure you've burned all the crap off! :twisted:

 

You're prob right there i'm just a bit of a scaredy cat :oops: