A 150 Victory and Cooling Question

[James Thompson]

Yesterday was big smiles thanks to help from this fine site and it's many knowledgeable folks :D I got another rectifier and after meticulously cleaning every ground and tracing and inspecting all the wiring it actually worked and nothing else burned up. The volt gauge gives a delightful twitch as the rmps go up. So after having it run for more than a few minutes I noticed the left side of the engine was much hotter than the right to the point I could not hold my hand on it whereas the other was only warm. Is this normal? Is it possible that chunks of the old disintegrated impeller may be stuck in some passage. I've never split open a power head to know how the water flows through the case

James

[1BadAction]

Yesterday was big smiles thanks to help from this fine site and it's many knowledgeable folks :D I got another rectifier and after meticulously cleaning every ground and tracing and inspecting all the wiring it actually worked and nothing else burned up. The volt gauge gives a delightful twitch as the rmps go up. So after having it run for more than a few minutes I noticed the left side of the engine was much hotter than the right to the point I could not hold my hand on it whereas the other was only warm. Is this normal? Is it possible that chunks of the old disintegrated impeller may be stuck in some passage. I've never split open a power head to know how the water flows through the case

James

Yes, it is very possible to have rubber lodged somewhere in the cooling passages.

This might not be the exact same as what you have but it's likely close

http://i.imgur.com/6xmS9Nn.jpg

[tlwjkw]

that one works "if" he doesn't have tha 40a water cooled reg/rec that made its "glorious" appearance in '89... 'bout tha only difference is tha hose from tha top of tha block to tha poppit that was added later............ after tha reg/rec kept smokin'.............

[James Thompson]

The diagram is very helpful thanks 1BadAction. I do have the 89 with the $600.00+ water cooled rectifier unfortunately. Yesterday I pulled the thermostat out of the cylinder head and had my son bump it over, the gush of water says Ive got plenty of flow to that point. the surfaces were corroded so I'll be cleaning that up and putting it back together tonight.

[James Thompson]

Update, the thermostat is bad. I can almost hear those familiar with this engine going "duuuh". It opened in a stovetop pan of water a little but is deformed by the corrosion. Now I'm worried about the state of all the other sealing surfaces, this Merc has had plenty of saltwater through it and sat for six years. It's rewarding to coax life back into an old engine that was left for dead though. I seem to be acquiring a taste for that choppy two stroke idle and smoke perfume

[1BadAction]

Now I'm worried about the state of all the other sealing surfaces,

Just don't take it apart. :eek: :D

Seriously, I wouldn't worry about it,. I've had to cut some salty bastards apart and the powerhead sealing surfaces seem to be pretty resilient when the gaskets are good.

[James Thompson]

I'll take your advice on that, thanks. I spent a good 45 minutes with the dremel tool this evening getting things cleaned up for some new stats, could you recommend a good marine supplier? Given the condition of these I'm worried about the poppet valve, how robust is it and the seal around it? I scanned through the basic multi-model clymer manual I have and didn't see a section on it. I'm assuming it's under the power head and I would have to split the motor? Given your advice and the hundreds of hours I've already spent on this boat project it's something I hope to avoid until I can test this engine and Checkmate on the water343665

[1BadAction]

The Poppet is on the starboard side under the area where the electronics are. Pretty easy to pop the cover off and do a poppet valve kit with new gaskets.

http://i.imgur.com/GvUFK9a.jpg

[James Thompson]

Thanks so much for your help, I'll have a look in it tonight. I'm learning quite a bit about what makes these Mercs tick. :D

[coffeeguy]

Try putting old thermostat in hot water( I usually heat it to 180-200F) and make sure it is working. I your case it would tell you if stat had been a problem.

[James Thompson]

I did give them both that test and they both open. The grommet around the port side one was deformed by corrosion to the point I think it was causing the blockage, it had some sea grass stuck in it too. I had a look into the poppet valve (now that I know where it is:rolleyes:) and there was plenty of corrosion there too but the diaphragm was good. I'm ordering new grommets today.