Exhaust Manifold Question

[LastLeg]

I am rebuilding my exhaust system, I had to remove the exhaust manifold in order to get the exhaust flang off.

I noticed 6 exhaust ports in the manifold, 4 showed carbon resin which I thought would be normal, however the 2nd port from the ouside (from both ends) show dampness in the inner lining.

Is this normal. The engine runs great.

[Dave Neptune]

Moisture??

LastLeg, there are both intake and exhaust ports on the A-4 manifold. The intakes should look fairly clean and the exhaust a bit sooty. Is that what you are asking?
If you think that the integrity of the manifold is questionable have it preassure tested. You could have a water jacket rusting through to an intake or exhaust runner.

Dave Neptune

[rigspelt]

I am rebuilding my exhaust system, I had to remove the exhaust manifold in order to get the exhaust flang off. I noticed 6 exhaust ports in the manifold, 4 showed carbon resin which I thought would be normal, however the 2nd port from the ouside (from both ends) show dampness in the inner lining. Is this normal. The engine runs great.

I just checked a photo of my ports from last year when I had the manifold off, prior to getting it professionally cleaned: similar to what you describe. I presumed it was normal. I presume that ports 1, 3, 4 and 6 are exhaust (dry and sooty), and ports 2 and 5 are intake (damp look).

[LastLeg]

ahhh... Intake and Exhaust then this looks perfectly normal, thanks for the reply I feel better now, obviously I am diving into this head first.

My plan was to dump both the head and exhaust manifold in solvent / gas hit it with the wire brush then then blow all of the ports passage ways etc with a compressor.

Would you recommend professional cleaning?

[keelcooler]

Leg, I had extensive rust chips in my manifold water jacket. You want to remove all scale so chips don't float up and plug/restrict the discharge.

I was able to do a good job cleaning her out with long stiff SS wire and acid. After cleaning, if you can hear chips remaining when you shake it, you may then want to bring it in for a pro clean.

Take a good look at the manifold studs for any signs of leakage at the block.

[Dave Neptune]

Cleaning

LastLeg, it would probably be a good idea to have the manifold "boiled out" while it is off the engine, that will remove the problimatic scale from the water passages.

CAREFULL, with the wire brush especially if you are using a power driven one on the mating surfaces. A good scraper will probably work better on the "FLAT NARROW" surfaces. With the brush you may remove to much material from the narrow spots causing sealing problems.

It's not thast big a deal once you get going. Many here to help you through whatever you come up against on this project.

Dave Neptune

[rigspelt]

Would you recommend professional cleaning?

I happen to live not far from a shop that does this kind of work. The guy chuckled at the small size of the manifold compared to the engines he usually works with. Came out looking like new and did not cost much, so it was a no-brainer for me.