Tools, Tips and Tricks

[beerman57]

Not really antique related, after getting my friends 1988 OMC 200hp, 25" shaft, running last weekend – impeller, oil, carbs cleaned – it started right up. Running on a flusher, water out the tell-tail hose, water flowing out through the prop – it was hot on the heads, too hot to be right. Reminded me of another one years ago, beat my brains why that one was hot, on a flusher. I’ve come to the conclusion 25" is too much for a single feed flusher.
We’re going to run it Wednesday, and hopefully catch dinner if it runs cool in the water, which I think it will. Going to get one of those duel feed flushers to see if he can do a decent flush after running in (OH NO, SALT WATER).
The motor I worked on before, I went all through it and never thought about 25" being a problem for the water pump.

[fleetwin]

Hmmm, these monsters usually have the opposite problem. This engine still has its original water controlled thermostat bypass in place?
Sometimes, the white thermostat flutes/prongs would get stuck in the swelled rubber thermostat seats due to salt pushing the seats out/deforming them. BUT, this usually only caused an overheat problem at higher speeds, when the thermostats were supposed to be off their seats.
Are both heads getting hot, or just one? I know the older v4 cross flows with the funky thermostats oftentimes overheat on the hose, but never really had a problem with the big loopers.
But, like you say, best to try it on the water first before getting in too deep. Regardless of whether or not a real problem exists, probably a good idea to get this gearcase off every couple of years to check/clean/lube the driveshift splines, as well as doing the water pump if the engine is used in salt water.

[beerman57]

I was wrong? 2nd time in the last 10 years!! Boat launched today and still hot, time to look at the T-stats.

[bluehaze]

I have the same motor, a 1989 Johnson 200 looper. It has the "extra long shaft". I have a single feed muff, weak well water pressure, and run 100 ft of garden hose to get to the boat. It has no problem cooling. The heads are just warm to the touch when running on the flush attachment. It takes a while for the water to start flowing out, but when it does, there’s a thumb sized stream of water pouring out of the telltale. There’s some funky water control valve that you may need to check out. Don once gave me a pretty good explanation of the cooling system on these motors. Maybe he’ll see this and explain it…..

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