Exhaust manifold to downpipe gasket

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MikeT
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Exhaust manifold to downpipe gasket

Unread post by MikeT »

Citrojim has identified the above exhaust leak (thanks again Jim). Citroen and Euro Car Parts do a kit for just over £15+VAT whereas my local store offer the gasket and springs only for £7.

I prefer the lower price but would it be a false economy otherwise I may as well buy the genuine Citroen kit?
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CitroJim
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Unread post by CitroJim »

Hi Mike,

Provided the cheaper kit contains the following:

"Brillo Pad" Gasket, Top Cups, Special Bolts and Nuts, Springs and Bottom Cups...

You'll be fine. I see little point in getting one for twice the money :wink:

One thing, if you do the job yourself, the old Brillo Pad can be an absolute shocker to get off as it seems to become one with the exhaust manifold spigot over the years. I once had someone argue blind with me that no such gasket existed and he even showed me the smooth, conical surface on his manifold as if to prove no such gasket existed. It was only when I dug into it with a sharp scriber and brought forth bits of woven wire that he believed me. A small cold chisel or good hammerable screwdriver will be useful in driving it off.
Jim

A bit of a Citroen AX fan...
MikeT
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Unread post by MikeT »

Hi Jim,

No, it's just the gasket and springs for £7. Looks like I'll be getting the genuine Citroen kit then.

I was wondering though, if it's spring mounted, would it maybe just have some play in it that could be cured by re-tightening the bolts - bearing in mind the slight engine/gearbox movement I've been experiencing?
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AndersDK
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Unread post by AndersDK »

Its not just a gasket which needs tigthening up. In fact its a ball-sphere moveable joint which is gas/leak tight (supposed to be). It goes by logic if you tighten up the bolts, the joint will seize - and something else downstream must give then. Most likely the expensive kat piping which is next downstream.

The bolts are made such when the nuts are torqued down on the cup washers, the springs are compressed to provide the correct tension on the moveable joint to keep it leaktight.

The "gasket" (which is a special sphered ring) will normally outlast a couple of complete exhaust sytems, so once replaced wont be any concern the next 5 years or so.
Anders (DK) - '90 BX16Image
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CitroJim
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Unread post by CitroJim »

You really need to replace the nuts and bolts as well Mike as the heat over the years corrodes them and make them very difficult, if not impossible, to re-use effectively. So GSF then...

No, tightening will not help. I expect what happened is when it had its new downpipe, the fitter did not replace the gasket, thinking, for reasons stated earlier, that there was not one there. He/she may have dobbed some exhaust paste around it to help seal initially but in my experience, exhaust paste has a very finite life of no more than about 6 or 7 months. I say this as your downpipe flange seemed very close to the manifold flange. Usually there is around a 1/2 to 3/4" gap between the two due tho the presence of the Brillo Pad.
Jim

A bit of a Citroen AX fan...
MikeT
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Unread post by MikeT »

Ok, I'll go to Citroen, GSF are 20 miles further and only a few pence cheaper.

Thanks Lads.
citronut
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Unread post by citronut »

quite offen the exhaust shops use a cheap fibre conned sealing ring, which lasts about five minnuites, with the movment at the joint the fibre one breaks up, also its usualy the springs wich loose there tension that allows the joint to become loose
regards malcolm