exhaust manifold temperature when overheating

[wayne smith]

my 305 runs above 200 at high speed back down to 140 when idling.

What would the exhaust manifold temp be when the engine is running hot?
I though about putting two wood stove thermometers on the manifolds and see if they are my overheating problem due to blockage and not allowing water to pass through my block fast enough........just a thought..

new impeller on alpha one drive....

 

[Brentathon]

Re: exhaust manifold temperature when overheating

If you have a 140F T-stat, then temps up at 200F sound too high.......to me.
Sounds like you're over-heating.

 

[BAproject]

Re: exhaust manifold temperature when overheating

do you have an IR temp gun (the are short money at an autoparts store)?

I have noticed on my engine there is a hot spot where the exhaust manifold bolts to the engine. The block/heads are running proper temp (at least on one side right now hahaha) the exhaust manifold is about 200 degrees right at the joint and a half inch away the exhaust manifold cools back down to around 150....

The temperature you are getting is from where, temp gauge? If so was the impeller done correctly and do you have proper water flow from the transom to the "t-stat" housing.... there's a lot to chase down to diagnose this problem, as I am doing the same thing as well