Leaking exhaust manifold after engine rebuild

[Arrow21pilot]

We rebuilt the top of the Merc 260 and when we put the exhaust manifold on and fired it up, we got water flowing out of the bottom. The manual says torque the exhaust manifold to 25 pounds. Am I to put gasket sealer on the manifold gasket or should I be looking elsewhere.

 

[P 0 P E Y E]

Re: Leaking exhaust manifold after engine rebuild

Lots of things can cause a water leak. Unfortunately most are caused by or not noticed by the mechanic at time of assembly.

a double gasket, a not poorly cleaned mating surface, a pipe fitting too loose. a crack, the wrong gasket, a gasket in wrong. An over tightened bolt.

I think I have managed to make all of the mistakes above. Granted I was 16 at the time, had a very heavy spinach habit and could only think about the search for a depository for my micro-biological tadpoles.

Water flows down hill. wipe off the water and look for the source. Check a plug to make sure no water is getting into the combustion chambers thru an exhaust valve.

 

[Bt Doctur]

Re: Leaking exhaust manifold after engine rebuild

If you mean where the exaust manifold bolts to the engine, then you have another problem. theres no water in that area.

 

[Arrow21pilot]

Re: Leaking exhaust manifold after engine rebuild

Nope, no issue. Forgot to tighten the riser. All's well and we're putting out a bunch of horsepower now with the new heads, intake and carb.

 

[P 0 P E Y E]

Re: Leaking exhaust manifold after engine rebuild

A happy ending........Congrtulations.