t reynolds
escanaba mi
Boat Name: impulse
Model/Year: 1982 c 22
Hull No. 10619
Hailing Port: escanaba mi |
 07/12/2013 5:23 AM Pacific Time
Two years ago I had an overheating problem,, local shop replaced impellor and head gasket. told me all was good... still overheating, I took it back in and they took the motor off the long shaft and found an o ring crushed in the line that brings the water up to the engine, so now no overheating but engine does not reach full rpm under load. engine idles fine and reves up just like the old days when in neutral, but will not come up to full rpm when in gear, forward or reverse.. its like the pitch is wrong on the prop. The only way that could be is if the shop put the wrong prop back on the motor. So I cant tell if its my prop or not,, It is stamped 9 1/4 x 6 1/2. is this the correct pitch and diameter for a Johnson 7 1/2 hp sailmaster on a cat 22. if this is the right prop what's gone wrong with my engine not coming up to speed?? It is midsummer and I am still struggling to get the motor running right thanks Terry Reynolds |
Greg Guenther
Belleville, IL
Boat Name: Magnificat
Model/Year: 1970
Hull No. 473
Hailing Port: Belleville, IL |
07/13/2013 6:19 AM Pacific Time
What my dealer told me many years ago was that the only way to really fit a prop is to experiment with different pitches for different applications. You could approach the dealer and borrow a lower pitch prop and try it out and then you will know for sure. I have a 10 hp Mercury "kicker" on my '22. It is heavy but my first mate is not a sailor and could not pull start the 4 hp Suzuki so I got a motor with electric start and tilt so if anything happened she could start the motor and get us to land. But then I digress. My OB has a 10" pitch prop.
I would try a smaller prop and see what happens.
Good luck.
Greg |
Greg Baker
Charlotte, NC
Boat Name: Sea Sharp Minor
Model/Year: Catalina 22 - 1984 - Swing Keel
Hull No. 11823
Hailing Port: Lake Norman Sailing Club |
07/13/2013 9:32 AM Pacific Time
You mighty also check to make sure the throttle linkage has been reassembled correctly and the ignition timing as well. You should be able to see the throttle butterfly without taking off too many things and verify it actually opens all the way at full throttle. I am not familiar with that particular engine but most outboards also have a sync adjustment between the throttle position and the timing advance lever. A miss adjustment here could cause the engine to not reach full rpm as well. |
t reynolds
escanaba mi
Boat Name: impulse
Model/Year: 1982 c 22
Hull No. 10619
Hailing Port: escanaba mi |
07/30/2013 9:01 AM Pacific Time
Ok I got my 7 1/2 hp Johnson Sailmaster to a reputable mechanic, and he replaced the electronic module, ($115.00), and the engine runs fine.. The pitch/diameter on the prop is 9.25X 6.5. I took the boat out in the harbor, and at full throttle the boat moved at an average of 6.5 mph. (not Knots). So now we all have some values to measure other sailmasters against.
Thanks to all the respondents who helped on this troubleshooting adventure.
Terry Reynolds |
