V6 exhaust manifold repair?

[SteveOS3]

I took the manifold pff on the weekend and found that two of the gaskets had practically disintegrated. The outcome is that the manifold flanges has been badly worn away in both places.

A new stainles one is way too expensive so my question is can the flange be rebuilt by welding and grinding flat or is it possible to add a new plate to the flange face?

Alternatively, can the whole flange be replaced if I source the right sort of steel plate?

Steve

[chiefyo]

Its a thick bit of metal so should be saveable , the tubes would present more of a challenge. Personally I would clean the flanges and build up with weld or alternatively fill in with braze its easier to flatten.

[phillpot]

chiefyo said:

alternatively fill in with braze its easier to flatten.

Exactly what I did, then lots of filing

[Philthefinger]

Steve

I have a couple I have taken of my s3c that you can have for the cost of the postage.
If they are any use let me know

Phil

[tvrgit]

Philthefinger said:

Steve

I have a couple I have taken of my s3c that you can have for the cost of the postage.
If they are any use let me know

Phil

S3C manifolds won't fit an S3 - they'll fit the engine, but not to the rest of the exhaust - the joints are in a different place.

[SteveOS3]

I don't know what the S3c configuration looks like but would it be feasible to cut the lower end off the S3 pipes and weld them to the upper end of the S3c?

[AutoAndy]

SteveOS3 said:

I don't know what the S3c configuration looks like but would it be feasible to cut the lower end off the S3 pipes and weld them to the upper end of the S3c?

See photo -Basically it was about the "C" manifold being short for the cats to fit, plus it has a sensor mounting fitted.

[Jakko]

Phil, my MOT last week had an advisory about a blowing nearside exhaust manifold. I have not yet stripped it down to investigate as it is fairly minor (I think). Mine is an S3C that has been de-catted, so your manifolds should be the same, I think. If they are going spare, I would welcome the opportunity. I would not sell them on, but will hold them for other members use in the event I don't need them. Joe

[Barkychoc]

I'd get a quote from an engineering place to see what they would cost just to mill a bit off - bet it won't be a huge amount.

[phillpot]

This was suggested on, I think it was, the Chimaera Forum, consensus of opinion was that it would be very difficult (= expensive) to hold the manifold securely enough to mill because of its irregular shape and four separate flanges?

S series manifolds may be a little easier as at least the three flanges are joined together mine aren't, I cut the links out, made filing a lot easier.


Even so it's got to be at least an hours work I'd have thought by the time someone's set the machine up and worked out how to do it, so there's probably £50+ (and the vat) unless you have a contact/friend who could do them in his "lunch break"

get the files out!

[AutoAndy]

Jakko said:

Phil, my MOT last week had an advisory about a blowing nearside exhaust manifold. I have not yet stripped it down to investigate as it is fairly minor (I think). Mine is an S3C that has been de-catted, so your manifolds should be the same, I think. If they are going spare, I would welcome the opportunity. I would not sell them on, but will hold them for other members use in the event I don't need them. Joe

Mine was de-catted as well. However they replaced the cats with straight pipe. Therefore the "hockey sticks" (L shaped its at the bottom) are shorter - See my earlier comment with picture. Still working looking for someone making longer hockey stocks to replace the cat sections on the "C" car - Economic suggestions gratefully received.

[chiefyo]

I have a decatted 3c and all pipes including hockey sticks are as original. The cats are replaced with two lengths of pipe with a three bolt flange at each end made to same length as cat and are a bolt in replacement.

[SteveOS3]

Phil, if my garage can't build up the weld I would like to take you up on the offer.

I should find out on Saturday if they have been successful.

Thanks,

Steve

[SteveOS3]

Chiefyo, do you know if the bolt-in section is a part that has to be made up or can it be bought?

Thanks,

Steve

[chiefyo]

[quote=SteveOS3]Chiefyo, do you know if the bolt-in section is a part that has to be made up or can it be bought?
Hello Steve according to the alternative parts list peninsular automotive are listed as a supplier.
Failing that getting them made should not be dificult the flanges are a standard looking exhaust item joined by a straight pipe.

[SteveOS3]

Thanks chief, I'll see if I can get some info' from them tomorrow.

Steve

[chiefyo]

Steve just to clarify - as shown in the diagram all parts between engine and exhaust are diferent on S3 and S3C and dont mix and match. Basically to go engine to exhaust on 3c you need manifolds, de-cat pipes and lastly hockey sticks. Engine to exhaust on S3 is manifolds and down pipes. Apologies if I am stating the obvious but didnt want you to end up with bits missing.

[phillpot]

Looking at the two drawings it doesn't look like it would be too much of a job to make an "adaptor pipe" to join cat manifolds to non-cat hockey sticks ?

[AutoAndy]

phillpot said:

Looking at the two drawings it doesn't look like it would be too much of a job to make an "adaptor pipe" to join cat manifolds to non-cat hockey sticks ?

..if only we could find someone to do it ecconomically - they might get a couple of orders quickly

[Top Gear TVR]

Its gotta be weld and a grinder, then a file, then some gaskets. Any half decent garage should manage it without issue. You might even get away with a bit of paste if its not too bad and all clean.

Big bucks are worth saving for the stuff you really want, not the stuff you need!