Exhaust Manifold Cracked

Razuddin

Hi Guys,

New member here needing a bit of advice. My cars been sounding a bit weird since I bought it. I always thought the exhaust manifold was blowing. Checked over the weekend and noticed that the manifold was cracked above one of the bolts. So I need to get hold of a new manifold and whip the exhaust off to see if anything else needs replacing. Now I really want to replace with a second hand manifold but im scared its going to happen again and I dont want that.

What do you think? Go for new or second hand? Any decent aftermarket ones that dont cost an arm and a leg?

PS: The cars a Vectra B 2.2sri

astra22bertoneauto

Ive had 3 cracked manifolds on my astra coupe. they all cracked down the middle just before where the downpipe bolts on. Vx make them to order about 2 - 3 months and cost about £80 IIRC.

I found by removing the precat the manifold did not get as hot and thus did not crack. Should be able to find a decent s/h 1 at a breakers or maybe someone on here has 1?

Aftermarket ones do give a nice increase in bhp but are costly!

Razuddin

Ouch! Not what I wanted to hear 🙁

Thanks for the advice though. Im going to try and see if I can get a hold of a good second hand one. I just hope it doesnt crack again, otherwise il have to look at changing it again.

When you say removing the pre cat im assuming you cut it off and welded another pipe on? Any downsides to this like fault codes popping up etc?

jwalker

There's a how to on here somewhere. The precat is in the top of the downpipe, you need to drill it out

Razuddin

Thanks for the advice guys. Need to start looking for a second hand one then...

flatbeat

i got one from an astra if they are the same

pm`d

Razuddin

Not sure if they are the same! Anybody else know

Daz

99% sure they are the same.

Sent from my GT-I9100 using Tapatalk

Razuddin

Hi Guys,

Have found one on ebay but it looks cracked near the bolt. Should it be like this or is it cracked?

http://www.ebay.co.uk/itm/370561790381? ... 1009wt_604

astra22bertoneauto

Mine always cracked where i have placed the red line (that general area). Ask the seller to check. If you do get it and find its cracked send it back to him.

The break between ports 2 & 3 where it bolts to the head is normal :thumbup:

Razuddin

Thanks for that mate. Ive been offered one for cheap by a forum member and most probably going to take it.

Now my only query is if that crack is normal then my crack is in a similar place on the manifold. Its near one of the tops bolts. If the crack in the picture is normal then the crack on mine is fine and doesnt need replacing. Im going to get my mechanic to give the car a good going over on the weekend and check exactly were it is