Silencer gasket mk3

Technical Area Engine, Transmission, Exhaust etc
2

Anyone know what size the gasket is between the silencer and centre section on a mk3 please?

 

Thanks

3

I can’t find the size BBB but it looks like a fire ring rather than a standard gasket - here is the cheapest I can find. 

4

That’s the correct one above, I can’t say what the size is though.

I used a flat gasket when fitting the Cobalt back box, it wasn’t very good and needed some paste to seal it and still leaks slightly.

5

Had similar problems many years ago with my MK1 Mick, when fitting a new aftermarket cat. Old cat, front pipe and catback had rebates for the fitted fire rings but at the time I was supplied with flat gaskets. New cat had flush flange seats without recesses. Fitted flat gaskets and blew badly - ended up reusing the very tired fire rings and they have been trouble free now for around the 15 years the cat has been fitted. I expect you would resolve your blowing issue with a fire ring gasket.   

 

6

 

I was only thinking this the other day. I need to remove my back box shortly as I can detect some undersealing needs doing up above and around it. Not a big job but easier to remove than struggle, I need a new gasket then and was looking at the original fire ring rather than the flat one…goes to that link to order, thanks

7

Thanks everyone for your replies, I’ve got a cobalt back box arriving on Wednesday so I’ve ordered one from eurocarparts for a mere £4.50, hopefully it’ll be the right one.

 

Cheers

 

 

8

Just measured the used original mazda ring gasket I have at:

Inside diameter 61mm

Outside diameter 76mm

Thickness 4.5mm

Can also recommend Loctite SI 5990 copper silicone high temp gasket sealer for aftermarket flange joints to the original Mazda mid pipe

9

Nice one

 

Thanks for that