V8 Exhaust leaks??!!

[bobtailed disco]

I am getting fed up with the exhaust blowing on my v8 disco. it is blowing from the manifold gaskets and downpipe gasket, I have replaced them a couple of times but it only lasts a couple of weeks and go's again. Does any one know if there is anything i can put on the gasket to help seal it?   
Many thanks Rob

[BigBlueBeast]

Simple solution, get rid of the dreaded V8!! Diesel is the way backward!

[bobtailed disco]

V8 All the way!!! At least mine don't smoke like a Diesel unlike a 4.6 i know!!!    lol

[BigBlueBeast]

Whoa, Whoa Whoa!!!! Don't insult the BBB! She is fine in every way except the engine! Piston Rings, head gaskets etc to be done before xmas!

[Range Rover Blues]

Mine kept doing that all the time.  I used the P38 header gasket, the twin port type that is all ali (lamintated) and OEM downpipe gaskets with exhaust assemply paste. It would last until I towed something then go again.

I binned the pipes and fitted a sports pipe with the same type of header gasket, I think the cats were blocked and it got more economical when i did it.

[bobtailed disco]

thanks for the advice. when removing the cats can i use that flexy exhaust pipe? or is there too much heat there?
Thanks Rob

[Range Rover Blues]

I'm not a fan of it, there's a lot of vibration which will cause fatigue and the airflow will be compramised.  What you need is an early 3.9 system which didn't have the cats fitted.  You can buy weld-in bosses for the lambdas, the EFi runs better with them still fitted.  If you do bin the lambdas you need to swap the TSR near the ECU to tell it to run open loop.

[Devon-Rover]

I got rid of the thin tin plate excuses for a manifold gasket and went for the individual composite gasket type ones you can get, then with a thin smear of fire gum exhaust paste on each side to help seal it, (and sticks them to the manifold and allows you aline the bolts without them falling off). Also tightening the manifold bolts equally along the whole manifold will help.
Not sure if they do help but the ARP manifold bolt kit looks nice too.

[Range Rover Blues]

I got fed up with blowing the composite ones aprt, they aren't that good TBH so I fit the twin port ones form the P38, they really are the best ones.  Don't use firegum on the cylinder head if at all possible, you never get it off.

A stud kit is a good move, if you can still get the manifold on, I fitted the tab washers from the earlier RRC abd bought an obstruction spanner to get to he back bolts.