Engine overheating

[wrmann]

My 1992 SN started to overheat last weekend. The engine is a 351 Ford with a Holly carb, 245 hours. I checked the hoses, pump impeller (replaced last year), oil cooler and the t-stat. All were working fine. I checked the oil dipstick and the oil was at a normal level and clear. No water or foam thank goodness. When I felt the exaust manifold, I noticed that the left manifold was cool but the right manifold was very hot. I'm thinking that I have some kind of blockage on the right side of the engine.

I plan to back flush the engine by removing the engine drain plug (the one that I remove for winterizing) and flush with water from a garden hose on the boat dock. I hope this does the trick. The boat is on Lake Hartwell, about two hours away from home. Is there anything else I should examine or try?

Also, I know the water pump is working because when I checked the t-stat I had to replace the gasket. In doing this I ripped the new replacement gasket but installed it anyway. When I started the engine, a small stream of water flowed out the ripped gasket. Should I use gasket cement when I replace the next gasket? Do you apply gasket cement to both sides of the gasket?


Thanks.

[Rick]

RE: Engine overheating

When you replaced the impellar were there any pieces missing? The temperature of the engine is maeasured at the T Stat so overheating means you usually not getting enough water or the T stat is faulty. To test for blockage you can run it without a t stat. It should run around 130-140. If there is a blockage then it will still overheat. Also check the hose connections on the suction side of the raw water pump and the oring on the strainer. If there is an air leak it will look like it's getting water but won't be getting enough

[TRBenj]

RE: Engine overheating

When would it heat up? At idle or at speed?

If at speed, I would suspect there is a blockage or the RWP could be the culprit- meaning either the impeller is toast or the pump isnt sealing and drawing air.

If at idle, I would suspect an air leak elsewhere- check your hose clamps and strainer to make sure theyre tight.