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mjdavis
08-16-2012, 08:52 PM
I have an 89 boat with a 351windsor. It runs great at about 160 degrees or so but occasionally, usually during idle, temp will slowly spike up to 225, the alarm sounds, temp keeps rising and then at 235-240 the thermostat must open because the temperature plunges quickly back down to 150-160. Then it'll run great for hours, then do it all over again.

Do I need a new thermostat? If so how simple is it to change out? And how do I identify the right replacement part?

Thanks so much!

Cloaked
08-16-2012, 09:00 PM
I have an 89 boat with a 351windsor. It runs great at about 160 degrees or so but occasionally, usually during idle, temp will slowly spike up to 225, the alarm sounds, temp keeps rising and then at 235-240 the thermostat must open because the temperature plunges quickly back down to 150-160. Then it'll run great for hours, then do it all over again.

Do I need a new thermostat? If so how simple is it to change out? And how do I identify the right replacement part?

Thanks so much!Yes and easy............call or visit www.skidim.com (http://www.skidim.com) Typically a 143 deg F thermostat for the 351. It's not that hard to find on the link I gave you.

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mjdavis
08-16-2012, 09:05 PM
Is this the one I want? http://www.skidim.com/prodinfo.asp?number=RP026002E

JimN
08-16-2012, 09:12 PM
I have an 89 boat with a 351windsor. It runs great at about 160 degrees or so but occasionally, usually during idle, temp will slowly spike up to 225, the alarm sounds, temp keeps rising and then at 235-240 the thermostat must open because the temperature plunges quickly back down to 150-160. Then it'll run great for hours, then do it all over again.

Do I need a new thermostat? If so how simple is it to change out? And how do I identify the right replacement part?

Thanks so much!

How old is the impeller? If it's more than a couple of years old, replace it. Don't try to re-use the gasket, either.

Cloaked
08-16-2012, 09:22 PM
Is this the one I want? http://www.skidim.com/prodinfo.asp?number=RP026002E Yes and Jim makes a good point. While you're ordering, get a new impeller and gasket....

.

thatsmrmastercraft
08-17-2012, 12:58 AM
If you have MCOCD, you can put the thermostat in a pot of water on the stove and bring the temp up and watch to see what happens. Can't always replicate having it stick, but I have seen some that do. Cheap insurance replacing it. Impeller too.