model 888 overheats@ high r.p.m.

[Boomyal]

Re: model 888 overheats@ high r.p.m.

What thermostat do you have in it? 160 or 180 Deg? Remove the radiator cap from your heat exchanger/radiator before you start it. Keep an eye on the temperature guage. When the guage shows that you are near your thermostat opening, watch the coolant movement in the heat exhanger. When the thermostat opens up, you should see a rapid movement of coolant by the filler neck. If you don't, you've got either a water pump problem or a thermostat problem. Keep the cap off, watching as long as you can before the coolant expands, wanting to overflow the filler neck. <br /><br />If you do not know the t-stat temp, get a thermometer and stick it in the coolant. When the t-stat opens, causing the rapid coolant movement, that is your t-stat spec. You can use that to verify the guage on your boat as well.<br /><br />This is a diagnostic luxury that one does not have with raw water cooling.

 

[Haut Medoc]

Re: model 888 overheats@ high r.p.m.

Boomyal, The water moves @ 140, which is the therm. temp. I believe the gauges, there are two of them. This is not a flow problem or restriction problem. I really think it's a blown head gasket. Thanks, Jeff

 

[steve n carol]

Re: model 888 overheats@ high r.p.m.

J.kopec, when the head gasket goes or a crack developes in the water jacket, head or block, ($ouch), the gases can be detected. the radaitor shop can test the cooling fluid for these gases w/ a sample. the last time I had this done the tech used what looked like a strip of paper. the paper turned color, he stuck this into the coolant, the paper turned color, ndicating the presence of the exhaust gases. I have heard that sometimes a powder is used as well.

 

[Haut Medoc]

Re: model 888 overheats@ high r.p.m.

Steve, I bought the gasket kit , so I'm gonna see what's up. Hope nothing is cracked, I guess I'll know soon enough. I never got it too hot so I'll keep my fingers crossed. Let you know how I made out. Thanks, Jeff

 

[Haut Medoc]

Re: model 888 overheats@ high r.p.m.

Took Steve's advice and had the water tested for exaust gases, and none were present.A cheap way to find out by the way! Having already checked everything else in the cooling system, I began to think about the heat exchanger again.The only thing I had not looked at was the fresh water section, because there's no way to. Anyway there's a used boat part store and lo & behold they had an exchanger like mine for $80. I put it on and it works great. Something inside the other exchanger is clogged or restricted somehow. So that's it. Since I only bought the boat last year I suppose it was a good thing to check all the stuff I did anyway, now at least I know what I've got. I want to thank everyone for helping me out especially achris & steve you taught me some good tricks for diagnostics. Thanks again!

 

[achris]

Re: model 888 overheats@ high r.p.m.

Jeff,<br /><br />Sorry I completely overlooked the heat exchanger. I have mine cleaned out every 2 years so it didn't occur to me that it could have been the problem. Glad I was able to help with a diagnostic trick. Glad to hear it's all sorted.<br /><br />Have a fun summer.<br /><br />Chris.......