ProV200 temp warning alarm…. ***UPDATE***

[GNEnsrud]

So Ive got this 94 ProV200 running pretty good, but it gives me an alarm and goes into limp mode if idle in gear for more than a minute or so.

I have already replaced the Poppet Valve. Didn’t appear to be stuck, but was the older valve design, so I put in a new seat/grommet, spring, and the newer rounded seal type of valve. Hoped this would fix the issue, since everything I found online said this was likely the issue….. nope. Problem unaffected.

Question is: what’s next? The tattletail stream is steady and strong from the moment the engine is started. My thought is to replace the thermostats at the top of each cylinder bank next. But would really like some experienced input before ai just blindly start replacing stuff.

thanks in advance for any constructive input you may have to offer.

 

[HST4ME]

It's 30 years old and should have had every serviceable part replaced in the cooling system including the t stats.

 

[HST4ME]

If you guys had more trees I'd move out there and work on yore shit.

 

[GNEnsrud]

It's 30 years old and should have had every serviceable part replaced in the cooling system including the t stats.

Head Thermostats, impeller, wear plate,…. What else?

 

[TimeBandit]

My 1991 Merc 200 H.P. set off the alarms during a houseboat trip in 1996. Too late, seized the engine.

I took it to Dick Sherer Marine for an overhaul early 1997, I took it out and it seized again.

Dick Sherer fixed it under warranty and handed me an invoice for $28.00, for the Thermostats they did not replace the first time. Idiots.

 

[GNEnsrud]

Replaced everything in the cooling system Im aware of. I think I found my problem……
Where the out-flow port is blocked, that is actually plastic from the housing that has apparently gotten so hot that it bubbled and deformed. How in the world does this component get so hot? I can see the engine getting hot without sufficient flow, but this component is literally submersed in cool lake water. Is this normal?

 

[GNEnsrud]

Put it in the water last weekend And idled it around for an hour. No alarm; no issues. Happy man…. Havasu bound in 2 weeks.

 

[DRYHEAT]

Replaced everything in the cooling system Im aware of. I think I found my problem……
Where the out-flow port is blocked, that is actually plastic from the housing that has apparently gotten so hot that it bubbled and deformed. How in the world does this component get so hot? I can see the engine getting hot without sufficient flow, but this component is literally submersed in cool lake water. Is this normal?
View attachment 1499823 View attachment 1499824

I’m no expert, but maybe it has been deformed by erosion, sand and silt in the water?