6r74c missing parts ??

[fleetwin]

Please replace the impeller with new OEM while it is apart…Be sure to replace lower seal gasket and oring that rides in the carbon seal…Might be easier to install the gearcase with the powerhead off, so the driveshaft roll pin can easily be lined up with the slot in the exhaust hsg.
Please check to make sure the screw in the shift lever bell crank is tight, and that the aluminum bellcrank is not loose/cracked….

[crosbyman]

I know a lot of folks have complained about Sierra impeller quality but I have never experienced this myself.

My impeller soon to arrive is a Sierra so i’ll go that route but I will keep an eye on it and notify any purchaser should I do away with my project motor.

thanks all for comments

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[fisherman6]

My biggest complaint with the Sierra impellers I have had is their propensity to take a set. The last one I had trouble with was in a OMC 5.5hp. I bought a ’62 Johnson 5.5 at an auction for $20. It was really rough but complete so I decided to go ahead and get it going. I replaced the impeller with a new Sierra part as part of a tune up service. I replaced the gearcase oil but did not reseal. The motor turned out to be a good runner, although a but tired from many hours of use. The gearcase ended up leaking so when I pulled it again to reseal I naturally checked the water pump. The impeller had taken enough set in one season to hardly put any pressure on the circumference of the pump housing at it’s farthest point from the drive shaft.

Soon after that I had one in my 4hp twin cylinder mercury stop pumping altogether because of excessive set. This one also after only one season. Now I try to stay away from Sierra impellers and typically use OEM.
-Ben

OldJohnnyRude on YouTube

[crosbyman]

well … the headgasket went on and I am getting 90lbs each cyl. 😀

not bad for a 60$ cdn 43 year antique

added the new thermostat, impeller ( 2 new OMC coils & wires going in soon )

parts are worth more than the engine but where can you buy a nice 6hp totaling around $250 cdn 🙂

next update… Spring 2018

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[fisherman6]

Nice! Ya, the parts are almost always more than the engine for me. As you said though, when you’re all done, you have a great little engine for not that much money. 🙂
-Ben

OldJohnnyRude on YouTube

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