Originally Posted by scumdog
I have found a tooth-paste looking heat-proof product works wonders at sealing exhaust manifold surfaces, better than any gasket.
San't remember its name but will find out if you want.
And that orange heat-resistant RTV also works but can look messy if you use too much and it oozes out.
Any thing you can find out would be greatly appreciated!
OK, here's my favourites, I tested then both on my hot-rod '55 F100 with tuned 429 Ford.
The headers on it have one badly warped exhaust port flange on each side (warped enough to drop a penny between the head and the flange!)
So I used these two: CRC "MANISEAL", it's the white paste type sealer that expands and goes hard when the exhaust heat 'cures' it.
Pros: Easy to put on using your finger to smooth it and easy to wash off your hands (and other places) before it goes hard, easy to scrape off exhaust port, flange etc when you take off and refit the headers/manifold.
Cons: Not flexible once set so any loosenes, movement may cause it to flake off.
AND: CRC Gasket 340, it's the orange/red RTC type stuff.
Pros: Easy to apply by squeezing out of the tube, easier than the above stuff to make a 'bead' around the header flange, remains flexible even after setting.
Cons: Messy to clean up and easy to get where you don't want! Is very obvious due to its colour.
I used one on each header, MANISEAL on drivers side and GASKET 340 on passenger side and both worked well at sealing that gap I mentioned.
Hope this helps.
PS: Sorry Stefan, I don't know what happened but my post 'ate' yours when I meant to quote it - maybe Ray or anothe rmod can fix it?