1962 5.5 Fisherman

[pjcdog1215]

Does anyone know the type of oil in gear housing and the oil to fuel ratio for this motor?
Any tips on replacing Impeller or cleaning out obstructions in water circulation tubes?
Runs good but not passing water.
Using aviation fuel 100 LL
Looking for service manual as well.
Advice GREATLY APPRECIATED
Pat

 

[Pappy]

Your oil ratio on that engine is 24:1. No less. That is a plain bearing engine and needs the extra lubrication. Do not listen to Billy Bob and Bubba about how much better today's oils are. Plain bearings need a good thick oil ratio.
No need for 100LL either. Regular 89 octane is plenty and even better if you get non-ethanol.
In order to replace that water pump assembly the powerhead has to be removed. Then the one or two nuts on the shift rod. Beyond that it comes off normally. Buy a powerhead base gasket.
Any grooves in the water pump housing it would pay you to replace the complete pump assembly. Get these parts while you can and keep the old housing as a spare.
Find any marine dealer near you and get gear oil from them. A manufacturers oil is specifically designed to continue to lubricate with up to 25% water in the gearcase. The OMC advertises this and you can get a small quantity while ordering your other parts.
Speaking of water. By all means while you have the gearcase off replace the shift rod o-ring. At this point I can almost guarantee it is leaking.