Thermostat

[cosmo]

Twin Detroit 8.2T. Do not overheat. Do not burn oil. Preventative maintenance advocate.

I pulled Starboard Heat Exchanger today to get cleaned and tested. In one of my many boat forums, I thought I read if pulling HEs, thermostats also should be updated especially since coolant is out.

Leave well enough alone? I would rather not since all is good but if its something that 'SHOULD' be done, the timing is right.

 

[Bmarler]

Wouldn’t hurt if it’s easy enough to get to. I would however, test it in a pan of water with a thermometer to be sure it acts how you expect.

 

[O C Diver]

If you've drained the coolant, and the thermostat(s) are easy to get to, change them out.

At 2,500 and 5,000 hours I cleaned the heat exchanger, replaced the thermostats, replaced the radiator cap, and the antifreeze. Thermostats, the gasket, orings, and radiator cap were likely under $100. Too cheap not to change for peace of mind.

Ted

 

[cosmo]

Thank you.

This is turning out to be; 'If you think you should, then you should.'

 

[cosmo]

I pulled my thermostats on starboard engine today. Operating temps are 180 degrees at 1900 all day long-zero problems. Thermostats are stamped 170 on the bottom. When ordering new 'stats, 170s again? My engine manual isn't very helpful in terms of marine setting.

 

[O C Diver]

I pulled my thermostats on starboard engine today. Operating temps are 180 degrees at 1900 all day long-zero problems. Thermostats are stamped 170 on the bottom. When ordering new 'stats, 170s again? My engine manual isn't very helpful in terms of marine setting.

Was this a rebuilt motor or are the thermostats factory?

My guess, and it's only guess, if you put the thermostats in water in a pot on the stove, they would start to open at 170 and be fully open at 180.

If you're going to borrow your wife's pot to do this, put the thermostats with water in a zip lock bag first. An infrared temperature gun works well for this.

Ted

 

[Bmarler]

I pulled my thermostats on starboard engine today. Operating temps are 180 degrees at 1900 all day long-zero problems. Thermostats are stamped 170 on the bottom. When ordering new 'stats, 170s again? My engine manual isn't very helpful in terms of marine setting.

Yes, absolutely. But be sure to test them before installing. In fact, do the old ones and the new ones together so you can see if they act similarly.

 

[Nepidae]

I'd just add, if it hasn't been said, that you should treat both engines the same.

I recent had an issue with the stbd impeller, which I rectified and due to that also did the port.

I think that might save a surprise later on.

 

[Antares]

170 degree stats are original spec for 8.2s. unfortunately they no longer seem available. I would keep them as long as they are functioning because of the 8.2s risk of damage should they overheat. 180s will work but there is less margin between normal running and overheating. My 8.2s now have north of 4400 hours. I keep a close eye on the temperature when operating.

 

[cosmo]

170 degree stats are original spec for 8.2s. unfortunately they no longer seem available. I would keep them as long as they are functioning because of the 8.2s risk of damage should they overheat. 180s will work but there is less margin between normal running and overheating. My 8.2s now have north of 4400 hours. I keep a close eye on the temperature when operating.

Thank you! Glad to hear you have so many hours. We love our boat so if I maintain these engines, my hope is they outlive me.