2005 Volvo V70 Catalytic Convertor Replacement

volvooh · Post by **volvooh** » 01 Jul 2021, 07:58

I am going to be replacing the catalytic convertor do to a two rust holes that have developed on the convertor near the bracket that cannot be welded. I have a couple questions. First, I would think there would be a gasket between the manifold fitting and the flexpipe fitting, but it appears there may not be one? Second, is there a torque spec for for the manifold bolts?

Post by **RickHaleParker** » 01 Jul 2021, 18:10

Gasket
Chassis -424999 Volvo part number 8642449.
Chassis 425000- Volvo part number 30650969.

Exhaust Manifold (cylinder head side) torque spec 25 Nm .
Exhaust system (to the turbocharger (TC)) 24 Nm .

Post by **vtl** » 03 Jul 2021, 09:39

Don't you want a 3" downpipe? Adds a couple of ponies, maybe even more for NA engine, and some nice grunt.

Post by **oragex** » 03 Jul 2021, 11:20

The mani has a metal gasket, I've reused it without issues - mine was a non turbo
After the cat is a 'paper' gasket to replace. The downpipe studs may last more, the ones after the cat were melted on mine. Just tighten 'tight' without over doing it. If you are replacing the nuts, may want to use black coated exhaust ones which don't get stuck. Shiny ones get stuck

volvooh · Post by **volvooh** » 15 Jul 2021, 06:01

Thanks, guys. I ordered the gasket from the dealer. It was only $9 so I figure is a good insurance policy against a leak.

Post by **GlennG2759** » 15 Jul 2021, 07:31

My cat was leaking exactly where yours is. I was able able to get some welding into the bracket attachment points on the cat. The reduced hole size I had left I filled JB Weld high temperature metallic paste. 1 & 1/2 yrs. and 18k miles later still holding up. If you haven’t bought a cat yet might be worth a try. Good luck.