Re: KF5 lower unit lube

[fisherman6]

Hi Bill,
I’m no expert on Mercs by ANY stretch, but I’m thinking you still need to dial in your high speed needle on the boat while running at full throttle. It’s likely starting to crap out from either too rich or lean of a setting on the high speed circuit. It is also possible that the magneto lever simply allows you to "over-advance" the spark to point of having a bad effect on the performance. There may be other factors involved here also and some of the Merc experts can probably help more with that.

I’m sorry for your loss with your brother’s passing. May his old motors live on in his memory. The QD-20 is a wonderful motor in my opinion. I have one and it is one of my favorites to run as a daily runner. The biggest thing to note with the ’58-’63 OMC 10s is keeping the gearcase sealed. Water intrusion will kill the 4-bolt case on a 10 horse pretty quickly. As long as it is sealed and full of oil, it will run a very long time and at a pretty good clip doing it.

The ’72 9.5 most likely has an exhaust leak somewhere either at the foam seal between the inner and outer shell or the water outlet under the cover. That is probably why the holes were drilled in the cover. It allows more fresh air in so the carb doesn’t inhale as much exhaust. This can be fixed with a but of work and they are nice running fishing motors as long as the motor mounts are not broken. It will not keep up with the 10 in a drag race though.
-Ben

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