Prop spins on muffs

[NathanY]

I just got my motor back together (20 HP Merc 1974) and started on muffs. The prop was spinning very fast. I have had johnsons that did that, but not that fast. Is this normal?

 

[KennyKenCan]

Re: Prop spins on muffs

Make sure that the gear shift is properly adjusted. Make sure that the enginge is idling at the correct RPM.

 

[NathanY]

Re: Prop spins on muffs

it seems to be idling a little high, but not too bad. Has been sitting for 10 years. Carb is rebuilt, new water pump, new LU oil, new fuel pump, new plugs, and new gas. This is beyond me. And water is only dribble-ing out the Tell-Tale. What is that about.

 

[KennyKenCan]

Re: Prop spins on muffs

If engine was sitting for 10 years, it is possible that insects have made a home within the cooling jackets of the engine. I would remove the thermostats and try running water thru the engine using the muffs to flush any debris out. You need not run the engine while doing this. Then clean all coolant hoses by disconnecting them and running water thru them. Also while you have the hoses off, I would flush the returns to the lower unit. DO NOT RUN ENGINE FOR LONG PERIOD WITHOUT EVIDENCE THAT WATER IS CIRCULATING CORRECTLY! $ $ Good luck, I hope that helps.

 

[NathanY]

Re: Prop spins on muffs

I ran a wire up the the tell tale and got it in about an inch and pulled it out and water started coming out. It was a steady straight line. So I know that is good. <br /><br />Prop is still spinning, can stop it with my foot though. I dont think it will spin in the water though. I think that the shift lever needs to be adjusted. I just ran on muffs, long enough to decarb.

 

[Hooty]

Re: Prop spins on muffs

Your shift adjustment is o-k. It's the lude in the l/u acting like a fluid coupling that's making your prop turn.<br /><br />c/6<br /><br />Hooty

 

[Walker]

Re: Prop spins on muffs

Also,you cannot flush the cooling system thru muffs without the engine running. If you can make water flow from the muffs through your engine without it running then your impellor is shot.