Help! Please! no forward gear except at low rpm's

[fishhead24]

I have a 1985 50 HP 4 cyl Mercury. Serial A100677. I just got it running last week after having to replace stator, trigger, and switchbox due to wire rot! It ran great, I ran it most of the day last Saturday with no problems at all! I took it out today and it ran fine and then while running at about 3/4 throttle , the rpm's skyrocketed, like it went into neutral. It will move in forward gear at idle and a little over idle speed. When I throttle up it stops pulling and races up! I thought maybe the prop had spun, but after checking it , It seems ok. When the motor is in forward gear I can turn the prop by hand easily in the forward rotation direction, it does make a light clunk every rotation. It will not turn in reverse direction. When in reverse gear I cannot turn prop either direction. When running it does ok in reverse. It does not make any odd noises at all while . running.Any help would be greatly appreciated. Thanks in advance. The more I think about it the more I suspect that it is a spun prop hub.I tried to turn the prop to see if it would move on hub, but couldnt budge it!

 

[Dman]

Re: Help! Please! no forward gear except at low rpm's

I would try a different prop that you know is 100%. You don't want to dump $ into a 'supected' problem. <br />I had a spun hub on mine and there is no way I could have found it without help. I could also spin the prop and couldn't tell it was spun. Try a different prop first. <br />D

 

[Trent]

Re: Help! Please! no forward gear except at low rpm's

Make a mark across the hub with a marker. Then go out and when it does it again stop. Look at your marks. If they moved (which I bet it does) you have a spun hub. If so carry it to a prop shop and have a new one installed.

 

[fishhead24]

Re: Help! Please! no forward gear except at low rpm's

Thanks for the replies! It was the prop. Just got back from running it with a new prop.