exhaust manifold

I'd buy some new manifolds NOW! If you
up-set the corrosion by poking it with a screw driver you'll go thru the wall.

74SkiNautique wrote: not to mention you would break just about every bolt that you try to take out. You would have to drill and tap everyone.

They can be a problem but tyically won't break. They are 180,000 tensile socket head cap screws. BTW, have you ever tried to drill one?? Not easy even with a carbide drill bit!!

Dan,
The bottom of the manifolds are not water cooled so they get hot which always burns the paint off - Then it rusts. It may just be on the surface. Where is the water leaking from?

I wouldn�t worry about that.... mine were in much worst condition than that, and all the bolts came out except the one on the pics that was almost gone..and it took me about 5 dremel discs to cut the bastard out





the rest of the bolts were rusted but came out with quite ease...



the manifold wall is thick and the rust is superficial


after some wire brush...


but as my engine is off i will sand blast them and give a new paint.

IMHO I would look at the riser to manifold area, check that gasket as if its gone it can leak to the motor (in my case they leaked to the outside)...Also the long bolts tend to rust and cut inside...had that problem...

water leaks


If I were U I would remove all, wire brush change all gaskets, new bolts and good as new...high heat paint will last some hours but eventually it will come off...

am I the only one that cant see those photos?

I wanted to compare, my bolt heads are in terrible shape but if the manifolds are not leaking, i dont plan on fussing with it until the fall/lay up time.

Personally I wouldn't touch those manifolds unless there was an exhaust leak or crack in the manifold. Your just setting yourself up for a miserable job that may not even be needed.

Take a look at Kaplas photo of the water leaking at the riser/manifold gasket and if you're leaking there that must be fixed, it is leaking on the inside as well as the outside. Those four bolts can give you fits to so get some pb blaster on them for a few days and work them out slowly, if you do break one they are not hardened and can be drilled much easier than the cap head bolts down below.

Thanks - turns out it was just the work computer that wouldnt let me see them, when i got home i could see the pictures just fine and I have the same looking bolt heads...what a pain.

Gcarbone - I would say the threshold for replacing the exhaust manifold (other than an outright crack, of course) would be badly pitted gasket surfaces. Most likely, this would be at the riser joint. Mine were leaking last year & I was able to sand the pits out. There are instruction on this in an old post, but essentially use a long board & keep the emery cloth flat. Good luck with your project.

This is all I need, right?

gasket

Can�t say It�s ok but my leaks are around there for the past 3-4 years bought the gasket 1.5 years ago and broke the bolt last year, left it like that until fall when I was going to tackle the offseason mainteinance...
Had the crack head so I had to remove them anyway...
The leak stopped eventually with my bubba skill I put some filling puty (used on plumbigs) and stopped.
Bs your risers are different than mine..your back bolts are shorter so I guess they won�t brake unless they are heavily frozen....
The ones I have are way long and are more prone to brake when force its applied...(too much torque on the thread I think.)

Sebastian,   Different risers, same issue.

bsucics, Put a little heat to it and go easy. There's a good chance it will snap but it's an easy fix once you get the riser off. There may even be enough bolt left to get some visegrips on, otherwise drill and easyout it. Those are not hardened bolts and drill out easy.

Got it. The clearance was so tight I couldn't get the wrench down on top of the bolt. Was able to file a bit and gently hammer it down on the bolt. After that, good to go. Nice design on the riser...

Fortunately, it looks like it was only leaking to the outside. Anything to keep in mind while replacing/reassembling, or just get to it?

79nautique wrote: getting the gasket on correctly and not blocking off the wrong cavity. Also make sure the gastket surface is nice and flat and doesn't have a hump to it.

I agree..correct me If I�m wrong, the gasket will tap the back cavity...

what's the purpose of blocking that back opening?

*Tech Tip - PCM Riser Gasket's Have One End Blocked Off, The Blocked End Goes Towards The Exhaust Outlet*