Offshoreonly.com - overheating

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Quote:

Originally Posted by Delta5 (Post 3081801)

Hi guys...the real problem here is that you are getting "hot spots" in the cylinder heads! It comes from not having rnoug block pressure at idle. In the old days we used a 5/8s hole in a restriction plate in place of a thermostat to get the 25 psi needed to coo, under rce conditions, in the 510 cid Reynolds (all aluminum with iron plated pistons, no sleeves) the 526 cid spacer motors and the L-88s and the original ZL-1s as without the restriction air pockets get real hot and boil small amounts of water all through the heads and the steam gets more of it boiling...hes the answer is mor water being pumped in and either a thermostat or a restriction plate for the size engine you have...there used to be a division of Chevrolet Engineering that always had these answers??? Hope this helps cool her dwon might not need another prop just more rpm!

dont think the thermostat has anything to do with it. i was running the boat with no thermostat and it was fine never overheated. it just started doing this. i had raise the idle up a bit think it was to be 600rpm but i took it to about 900 seem like it was idling low. how i get the more rpm and not change my prop?

Get your motor running right (might need better fuel and more advance, like a total advance of 38-39 degrees) and it will put out more horse power and rpm...hour new engine has more horse power you just aren't getting it! It should get up on a plane faster as well unless your low rpm has less torque, not likely though and the the heating at low rpm IS because not thermostat!

thanks for the info man i will get a thermostat that is what i was thinking but people told me it dont need one. as for the motor running right it is i just got this motor is idles fine and dont miss a beat. as for the fuel i live in barbados and this is the only fuel we use. i been running the old motor for almost two years and never had a problem with the fuel. but thanks again i will replace the thermostat.