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BF30 t-stat stuck open?

Mbett

New member
I had salt build up. I replaced impeller and thermostat. Did deep cleaning with salt away and descaler. Finally cleared the clogs and the pee stream is massively strong now.
I’m not positive the thermostat isn’t stuck open. That doesn’t sound likely and I don’t think you can put them in “wrong”. Engine doesn’t overheat now but on the flip side, the pee isn’t warm. I’m running it in cold ocean so not sure if that plus the fact the channels have been completely cleaned out just means things are working great. Engine head seems like it gets warm/hot.
Can you put the Tsat in wrong and is there a way you can tell if it’s stuck open? The pee stream stays very strong at all temps and rpms. Early 2000s Honda 30

Thanks!
 
I had salt build up. I replaced impeller and thermostat. Did deep cleaning with salt away and descaler. Finally cleared the clogs and the pee stream is massively strong now.
I’m not positive the thermostat isn’t stuck open. That doesn’t sound likely and I don’t think you can put them in “wrong”. Engine doesn’t overheat now but on the flip side, the pee isn’t warm. I’m running it in cold ocean so not sure if that plus the fact the channels have been completely cleaned out just means things are working great. Engine head seems like it gets warm/hot.
Can you put the Tsat in wrong and is there a way you can tell if it’s stuck open? The pee stream stays very strong at all temps and rpms. Early 2000s Honda 30

Thanks!
Are you watching the live temp on a gauge or infrared gun to confirm it's not reaching full operating temp? I wouldn't judge the pee stream warmth on if it is stuck open or not, some just don't get that warm depending on where the split to the tell-tale is. Can't really put the t-stat in wrong, it wouldn't clear the cover. You can always put the t-stat in warm water to see if it opens, then closes after you take it out. If it's stuck open you'd see it stuck open when you take the cover off.
 
Actually, if it's working as designed, the thermostats are supposed to fail "open". Pull it and check it. They're really obvious.....
 
Actually, if it's working as designed, the thermostats are supposed to fail "open". Pull it and check it. They're really obvious.....


thanks everyone. I’m not at the boat all the time so wanted to have some ideas. I’ll take it off and test it. I thought maybe someone familiar with this exact motor would know where the telltale tees off and if the stream ever changes strength when the t stat open. The engine went from overheating just above idle to no overhead even under long load and extremely strong pee. I hadn’t seen it like this as it’s a relatively new motor to me. Just wanted a way to check that I wasn’t causing eventual damage with it sticking open. There is no temp gauge and I don’t have a gun.
 
Pulling that t-stat will also show you how good a job you did cleaning/removing crap from the cooling passages.

One thing of note, that "stream" should remain relatively constant as far as volume is concerned, with t-stat open or closed. If you see it cut drastically or it stops completely, you should know the problem is usually right there. A tiny piece of crud is usually involved.
 
Pulling that t-stat will also show you how good a job you did cleaning/removing crap from the cooling passages.

One thing of note, that "stream" should remain relatively constant as far as volume is concerned, with t-stat open or closed. If you see it cut drastically or it stops completely, you should know the problem is usually right there. A tiny piece of crud is usually involved.

sounds good. I’m confident it’s just over performing now but I will take it off and inspect.
 
Pee stream should NOT be very warm at all. It's a "bypass". Meaning that it isn't actually involved in engine cooling. It's only there to indicate pump operation.

It will get HOT when you shut the engine down.
If you don't believe me....
...stick your hand under it while running and then shut the engine off with it pouring on your skin.
But be ready for the heat!
 
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