Exhaust Manafold temp question

[agallant80]

I noticed on my 5.0MPI with cats that ideling at the dock one of the manifolds was hot to the tuch too hot to touch for more than 5 sec or so and the other was warm, when I upped the idle they were both the same temp. Is this normal? One manifold can be warmer than the other? No alarms went off and my temp was fine. Just wondering.

 

[MarkSee]

Re: Exhaust Manafold temp question

one of the manifolds was hot to the touch

Are you checking the manifold or the riser/elbow? I've always checked the riser/elbow not manifold as that's way too hot.

It is common that one side will be slightly warmer than the other side especially on a garden hose or at idle.

Mark

 

[Don S]

Re: Exhaust Manafold temp question

They do that on non-cat manifolds, and I would assume yours would do the same thing. If you can hold your hand on it for 5 seconds, it's only around 160?, and not a problem.
As you increase the throttle, you also increase the water flow from the raw water pump. The water at low rpm is just taking the path of least resistance and going to the easiest manifold to get out, and one side gets warmer.

 

[tpenfield]

Re: Exhaust Manafold temp question

Yes, it seems that with the water flow through the engine and out the exhaust, one side gets 'favored' over the other. the fact that they even out at higher RPM should be re-assuring.

On my previous boat, at idling, I had 1 warm and 1 cold riser/eblow.