Exhaust gum

[Rusted Pistons]

Hi guys - looking for recommendations! I need a temporary/last-as-long-as-possible repair on my exhaust. I've used the likes of Holt Gun Gum before and it just blows off the first time you exercise the rev needle. I need to seal blowing manifold-to-cat flanges so there's an awful lot of heat and pressure.

Wire brush the rust and fill with chemical metal perhaps?

[mk2cossie]

Try and get them as clean and flat as possible and use a new gasket woukd be my suggestion

Generally if it is before the catalytic convertor or a lambda sensor you don't/shouldn't use any for of sealant that gives off vapours that can harm either.


Having said that, I would use some VHT silicone sealant and leave it to cure fully before starting and see what that's like

[Rusted Pistons]

It's not the gasket - it's the actual flanges. They're known curse word spots on the Lexus LS400 and need replacing/welding up - neither of which I can do at the moment!

[rapidyellow]

if they do sell a gasket that goes in that place then use a thin slither of gun gum either side of the gasket and get it all bolted down well [and quickly], give it ten mins then just let the car idle for a while.

I have used that method on various cars over the years with no probs

in fact I have had more good results at the hot end of the exhaust using gun gum, than I have in the middle or back boxes joints.

[saabsled]

High temp Sikaflex.