Exhaust Manifold Temperature differents

[digger202]

I have just replaced the exhaust manifolds on a 4.3 Merc.. While running in the driveway with the water muffs on I noticed that one manifold was heating up alot more than the other. The exhaust outlet had very little water coming out with the exhaust compared to the other outlet. Is the temperature variance due to lack of flow because of low RPM ?

 

[MarkSee]

Re: Exhaust Manifold Temperature differents

Welcome to IBOATS.

Do you really mean exhaust "manifold" or exhaust "riser" that you are checking?
My manifolds will become very hot but the riser which is on top of the manifold will be cool or slightly warm.

If you do mean riser, it is normal to have a slight temperature difference with the main thing being that the top of the riser should never get so hot that you'd have to remove your hand.

Mark

 

[Chris1956]

Re: Exhaust Manifold Temperature differents

Well, Something is wrong. Did you replace the risers as well? If not, one of them could be clogged. If so, maybe the gasket between the two is installed incorrectly. Pull the supply hoses and run the motor and verify both get about the same amount of water.