I have a 1982 Pearson Cutter with a Universal 5444 engine and have an overheating issue. I replaced the impeller (the old one was still good with no blades missing) and checked the HX. I then drained and flushed the block but now can't get the block completely refilled. I think I am getting an air block in the cooling system which is possible especially with the water heater plumbed thru the engine. Does anyone know of a technique to refill the block without getting an air block? It could be the thermostat, but the engine heats up very fast after a short few minutes when started from cold.
Try opening the pressure relief vent on the top of the water heater.
Look for any loops in the hoses where air can get trapped. All hoses should slope upward to the highest point in the cooling system, which should be the Expansion tank.
https://pearson365.com/forum/index.php?topic=2119.0
Sometimes just letting the engine sit for a while lets the coolant gurgle down through the internal passages. See also if you have coolant reaching the heat exchanger. Confirm there are no internal blockages in the exchanger.
I have the same engine in my 1982, 367. There should be a bleed screw on top of the thermostat housing. Loosen this and you should have air coming out and then the liquid will follow. However, I found that this is not a sure thing. What I have done and found this effective, is to loosen the fill cap and let some air out this way. The first time I did this I was shocked at the amount of anti-freeze that filled it from the expansion tank and the volume of air that escaped. There is another bleed point on the engine on the lower port side and though it is a pain, you can get the air out from the lower parts of the engine this way. This has always worked for me, so good luck
Mike Meier
Capn,
Attached are two pictures that illustrate what Mike is talking about.
Thanks everyone for the advice. I have ordered a new thermostat and some new hoses. As soon as I get those on, I will try your advice.
In my message, I should have made clear that the fill cap is the one on the exhaust manifold. The fill cap on the expansion tank, I leave off during this process. The manifold cap should be eased off just a little because there is a lot of anti-freeze that wants out. Good luck Mike Meier
Thanks to all for the advice and information. I did discovery an internal blockage in the HX and was able to clean it out with a water hose. It seems this has solved the problem as I ran it under-load at the dock. I'll know more once I take it out.
Good to hear you found the problem. Keep an eye on the FW coolant level when you do the sea trial.