Water in cylinder 15hp '75

[kbait]

Replaced impeller/thermostat recently, and upon next run wouldn't idle well. Checked plugs and found water on lower one. Pulled head, and sludgy looking watery/fuel mix found in both cylinders (more in bottom one). Replaced head gasket w/no improvement (water still evident on plug). I have ordered bypass cover gasket and exhaust cover gaskets, but was wondering if that's indeed the cause, as it happened immediately after aforementioned service. Water tube seemed to stay w/powerhead normally during lower unit removal/installation, and cools normally. Could I have folded the upper grommet over, even if it stayed there during service? Would that cause water intrusion into the cylinder anyway? Any thoughts appreciated! (you too, BK)

 

[Rick.]

Re: Water in cylinder 15hp '75

kbait: I think your on the right track with your thinking. I'm voting for the exhaust cover gasket if your head isn't leaking. A word of advice here. You have to pull the power head to get the exhaust cover gasket out so I would also replace the upper water tube grommet while you have the power head off. It's just a good time to do it not that I think it is part of your problem. Weird that it would start right after you changed the stat. so that is an area for further inspection as well. Best of luck. Rick.

Edit: You might want to try simply tightening the exhaust cover bolts first. I did that with a 9.9 and it stopped the water ( I only had it in bottom cylinder) until I got the gaskets.

 

[bktheking]

Re: Water in cylinder 15hp '75

Is the water tube grommet in the exhaust housing new?

 

[kbait]

Re: Water in cylinder 15hp '75

Thanks rick. I was wondering if I could get to the bolt. I had the powerhead off last year for the dreaded upper mounts.. Still don't like the timing of the issue. (And I tried tightening the exh. bolts I could get to..). Also, when testing it after head gasket change, I had water quickly pooling under the bottom of the head, from where I couldn't determine. I then re-pulled head, tightened all the cover gaskets, re-torqued head, and that water leak stopped- but after running for quite awhile, still with the wet plug/poor idle. Maybe my exhaust gasket just blew out at the wrong time for diagnosis.. ??

 

[kbait]

Re: Water in cylinder 15hp '75

Hey BK. New bottom grommet at impeller change. I don't remember a problem when I had the powerhead off at upper mount replacement last year. When I did the impeller change, the water tube seemed to stay in like it should, and re-assembled nomally..

 

[bktheking]

Re: Water in cylinder 15hp '75

Just to add to it, it wasn't there before you replaced the stat, you need to retrace the work already done.

 

[kbait]

Re: Water in cylinder 15hp '75

I ordered a new water cover gasket (stat) also, as I installed the new tstat w/o replacing old one, which looked fine/intact. Could that cause water intrusion??

 

[Rick.]

Re: Water in cylinder 15hp '75

It could and like I said I would look there first. Reusing gaskets (although I do it myself) is not a very sound idea. These 9.9's are pretty easy to pull apart and I have to admit I'm a little on the cheap side but I will use the excuse parts are 40 miles away from my shop. You'll fix your problem I'm sure. Rick.

 

[kbait]

Re: Water in cylinder 15hp '75

I'll do the t-stat gasket and give it a test.. Thanks!!