Changing exhaust gaskets - advice?

[PaulyV]

Hi there,

This weekend I am planning to change the exhaust maifold gaskets on my friends 318i.

I have read the various reports from people here who have tried it, and as such he has been soaking the bolts in WD-40 night and day for much of this week and will continue to do so until we start work on Sunday.

Other than having the engine warm is there any other advice from people that may help?

Do I need a jack to get the car in the air to undo all the bolts?

Am I better gently forcing the bolts or starting the unscrewing process with a firm tap?

best wishes

Pauly

p.s. Got my car back from the garage today after the MOT work - feels good to be back on the road.

[noney82]

just take ya time with them work them one way then the other and so on till they are out then when they out give them a good wire brush clean up. you dont need to jack car can be done from under bonnet other than seized bolts its faily easy to change them. you dont want engine too warm or you'll take ya skin off ya hands, good luck mate

[Gwynleym10]

If I were you I would buy a complete set of new studs and bolts as well, then you will have done a proper job!

Will come to under Ԛ£20 from BMW, think you can get them from ECP for m40's as well.

As said take your time make sure you have enough socket extensions and wear a couple of pairs of gloves if your doing it with the engine warm.

[PaulyV]

Thanks for the words of wisdom thus far. I guess it begs the question what if we are unlucky and a bolt shears? Are they the 10mm ones on GSF?

Also would someone be so kind as to tell me exactly which gasket I should be buying from GSF, there seem to be afew!

best

Pauly

[Gwynleym10]

Not sure what size they are, GSF website is a little confusing!

ECP webiste lists them more clearly!

It won't be much more from your local dealers.

You need a exhaust manifold gasket/heatshield, all the same bit.

Might be worth getting a down pipe gasket as well just incase you decide to do that as well.


Thinking about it, if you do get studs broken/stuck you will wont to remove the whole of the manifold, it makes it easier.

Start with the maifold to downpipe bolts, then get the head to manfold bolts off. If your thinish and the car isn't lowered it is possible to do the downpipe bolts without jacking it up, but it makes it more of a pain!

Don't spray WD40 in your eyes!

[PaulyV]

WD40...eyes....sounds like the pained voice of experience!

Many thanks

Pauly

[bigmattpowell]

i notice my 318i m40 hasn't got a heatshield on the exhaust manifold (to protect the plugs/leads i presume) does this mean someone has bodged it and not even used a gasket or are they separate from the shield?

[Chris-W]

They are integral to the gasket, but are prone to snapping off / disappearing. I doubt you don't have a gasket.

Don't spray WD40 in your eyes!

Good general lfe advice there!

[bigmattpowell]

Good news, made me worry about what other bits of the car someone decided were "optional", cheers.

[Templ8e30]

Here's a little known engineers trick for you, tighten them slightly before loosening them to avoid shearing them off

Also try to get some plus-gas or other quality penetrating fluid from an engineers supplier. WD-40 isn't half as good as the proper industrial stuff.

Cheers,

Iain T