trans cooler and running hot

[keykev]

anyone ever popped the top off a trans cooler on a 1961 chris craft with a 283 flywheel forward engine. my motor is running hot on that side.it usually runs around 110 since there is no thermostat on these engines but now can reach 140 just putting around, never did that. I don't think its a head gasket cause it just runs to well and my vacuum gauge is steady at 16 at idle.impellers are new sherwoods. any ideas? I love this very difficult, hard to reach anything boat motor. thanks.

 

[alldodge]

Ok 140 is not normal for what your use to, but it might be a gauge or sender. Even if 140 is correct I still don't see an issue because the motor is not over heating. Why the concern?

 

[keykev]

it never ran that hot before unless I pushed it a little which I hardly ever do because of it untouched age with 1537 hrs on it in mostly fresh water. it happened all of a sudden. my gauge and sender are good as I scanned it everywhere with my heat gun. the concerning thing I should have mentioned is although exhaust manifold and engine temps don't exceed 130 which never happened before (more like 115) the starboard exhaust hose will reach 190 only about 6 inches beyond the manifold outlet while the port side never breaks 100. while this is happening there is still plenty of water exiting both pipes with starboard side looking like I am running a steam boat. i'm thinking I am going to install the new manifolds I have here and also a new cam in the Sherwood pump I also have. the lake here has invasive weeds in it that the state does a decent job of trying to control but will never be100%. I was asking about the trans cooler cause there is a cap with a nut on top it that definitely comes off although I never removed it. the fly wheel forward engine is a bear to work on and tough to access anything. my friends with ski boats have problems a few times with weeds making it through the pump and lodging at the bottom of the cooler blocking flow but never have on this boat. thank you for your help.

 

[alldodge]

Being your well aware of your boat and what is and is not out of the norm. I would say something is causing a restriction area as your aware of. Where the restriction is can be many places.

Thermostats are not a bad thing, getting a motor up to operating temps allows them to work better. The best motor runs its best at almost burning up temps. Thermostats also help keep the block and heads completely full of liquid. Without a thermostat, air pockets can form

That said, back to your issue. As with the ski boats, back flushing and disassembling components is about the only way to find where the issue is. Can try to install clear hoses at different locations to see if you can find bubbles.

 

[keykev]

that's what I.m thinking to. its early and cool here in ct. so I,m going to it shortly to pull that manifold, back flush the cooler, and the block, pull the pump so I can access the block drain and clean out the crud that always builds behind it, put the new cam in the Sherwood, put a new manifold together, and do a leak down test on that side to rule out a head gasket (compression decent but not great) although I don't think that's my problem as the motor starts easily, runs smooth at all speeds, and has a very steady vacuum reading of 16.5 at idle. the outlet hose off the head to manifold is only about 2/3 inches long so its a little tough to put a clear tube in there although it can be done, I will just have pull the 90 degree fitting off the head and just cut a new gasket for it. might be a good idea to try that first. hope wifey not looking for me today. thank you sir...