Planning Exhaust Manifold Replacement This Spring

[nd4spd]

Hey Guys,

My slight water jacket leak turned into a gusher this summer. I've got it patched with some epoxy for now, but don't like running like this. I'm planning to replace both manifolds this spring. Has anybody here done this already? Any advise? Any recommendations for other jobs to tackle while I've got them off?

I don't want to go down the road of trying to grind out the crack and weld it closed. Another problem I've noticed is a significant amount of loose corrosion product inside the manifold when I remove the drain plugs. This causes me concern for wall thickness between the exhaust & water jacket sides.

For anybody that's curious, my '92 Comp has only operated in fresh water.
Thanks,

-Adam

IMG_20140808_134300.jpg

[CJD]

From the first run our exhaust manifolds are rusting away...so rust scale is completely normal and nothing to worry about when draining. In fresh water it should take several decades to rust through.

A crack is a different thing. Was it from a previous freeze? If so, best to look very closely at the sides of the block while the manifolds are off, for cracks there.

[nd4spd]

I don't know what caused it. The crack was there when I bought it. I can only assume that it froze.

[SUPRA_ALLEGRO_LANE]

Looking at replacing mine also. I have found a few options for performance headers but still haven't decide which direction to go yet. I'll post what I have found so far tomorrow.

[wotan2525]

Just a couple of tips -- soak the hell out of the bolts with PB blaster or penetrating oil for a couple of days before you start to remove them. Give them a liberal coating of anti-seize before you reinstall.

It also helps to get 4 bolts that are the same size but twice as long. You can put these into the front hole and the back hole to help "align" the manifolds before you put the other bolts in. They are heavy and it sucks trying to get them in the right position AND thread in the bolts, using the longer ones makes this a lot easier.

[nd4spd]

Thanks for the tips guys! Excited to get this over with...

[suprasaltareaud]

I put some gasket goo onto the gaskets and put on the manifold because it is hard to line it up and hold the manifold and the gasket etc. Helps heaps.