Stuck prop

[1648grizz]

Have a 1992 70 HP Force that has been sitting 15 years. It was a free boat and it runs great. The prop shaft has a slight wobble and was trying to remove prop so I can straighten shaft and identify prop pitch. Man it's stuck bad. I tried to make a puller with a pitman arm puller and some chain but would not budge, started to bend blades. Is cutting off a badly stuck prop sometimes the only option ?

 

[DaleH]

Heat prop, heat gun or heat hammer, throw ice on it. Repeat. Try to concentrate on the first inch of the prop from the hub, as that with any taper feature will be, and tapers can naturally lock in place!

Also take 1-part each acetone & auto trans fluid (ATF) & mix, raise OB & drip onto propshaft, as it is THE BEST penetrating fluid EVER! After or with the above, if still stuck, with rubber mallet, whack prop hub, then prop body, then wood against prop hub to push it off.

On one boat we backed off the prop nut a few turns, but still had the smaller cotter pin in it and we put it into reverse (in the water, duh, ... but didn’t want to lose the prop in 10‘ deep water, LOL) with boat tied securely to a dock, and with power in reverse, it knocked the prop loose.

You might see a counterbore in the end of the prop shaft, where that end was supported on a lathe. With the prop off and out of your way, you can use that as a ‘visual‘ in neutral, as you spin the prop shaft & see if that circle ‘wobbles‘.

 

[1648grizz]

Heat prop, heat gun or heat hammer, throw ice on it. Repeat. Try to concentrate on the first inch of the prop from the hub, as that with any taper feature will be, and tapers can naturally lock in place!

Also take 1-part each acetone & auto trans fluid (ATF) & mix, raise OB & drip onto propshaft, as it is THE BEST penetrating fluid EVER! After or with the above, if still stuck, with rubber mallet, whack prop hub, then prop body, then wood against prop hub to push it off.

On one boat we backed off the prop nut a few turns, but still had the smaller cotter pin in it and we put it into reverse (in the water, duh, ... but didn’t want to lose the prop in 10‘ deep water, LOL) with boat tied securely to a dock, and with power in reverse, it knocked the prop loose.

You might see a counterbore in the end of the prop shaft, where that end was supported on a lathe. With the prop off and out of your way, you can use that as a ‘visual‘ in neutral, as you spin the prop shaft & see if that circle ‘wobbles‘.

Thanks for the reply, I don't believe there is any taper on the shaft. I believe it is a Mercury 13 spline prop as Mercury was building Force motors in the 90s Not sure heat will do it with the rubber insert. The prop is in fair shape but the shaft is bent, I may just go with it for now and see how the motor runs out on the water. I will try your oil mix and keep applying this winter.

 

[nccatfisher]

Use the mix he said or use this stuff. It is great and won't take the paint off everything it comes in contact with.
https://www.walmart.com/ip/Sea-Foam-DC-14-Deep-Creep-16-oz-Aerosol/38755122?wmlspartner=wlpa&selectedSellerId=1122&&adid=22222222227026728211&wl0=&wl1=g&wl2=c&wl3=52587036551&wl4=pla-84468172631&wl5=9009954&wl6=&wl7=&wl8=&wl9=pla&wl10=101593696&wl11=online&wl12=38755122&veh=sem&gclid=EAIaIQobChMIopLho9K67QIVBa-GCh0UZgCgEAQYASABEgKHmfD_BwE

 

[Pappy]

Aluminum prop I take it?
Try the above but I think your friend here will be a cut-off wheel. Cut the outer can in a couple of places then work through the rubber hub.....this part gets nasty. Inner hub all you have to do usually is cut it in one spot and break it open and off.

 

[1648grizz]

Aluminum prop I take it?
Try the above but I think your friend here will be a cut-off wheel. Cut the outer can in a couple of places then work through the rubber hub.....this part gets nasty. Inner hub all you have to do usually is cut it in one spot and break it open and off.

Yes aluminum prop, I think it will need to be cut off.

 

[CedarRiverScooter]

If shaft is bent you will be in for a lower unit rebuild. Shaft needs to be really straight to run smooth, it is pretty hard to get it to bend back that little bit.

I would start looking for a used LU or a different motor.

 

[1648grizz]

If shaft is bent you will be in for a lower unit rebuild. Shaft needs to be really straight to run smooth, it is pretty hard to get it to bend back that little bit.

I would start looking for a used LU or a different motor.

Been watching many vids on how to straiten a shaft with a hydraulic jack, looks easy. The motor runs great and has low hours. Have nothing to lose as the boat, motor and trailer was free.

 

[RaisedByWolves]

If shaft is bent you will be in for a lower unit rebuild. Shaft needs to be really straight to run smooth, it is pretty hard to get it to bend back that little bit.

I would start looking for a used LU or a different motor.

Been watching many vids on how to straiten a shaft with a hydraulic jack, looks easy. The motor runs great and has low hours. Have nothing to lose as the boat, motor and trailer was free.

With what you're going to go through to do that you're still better off going for the whole lower unit.

You might even luck into one that dosnt need seals.

 

[1648grizz]

If shaft is bent you will be in for a lower unit rebuild. Shaft needs to be really straight to run smooth, it is pretty hard to get it to bend back that little bit.

I would start looking for a used LU or a different motor.

Been watching many vids on how to straiten a shaft with a hydraulic jack, looks easy. The motor runs great and has low hours. Have nothing to lose as the boat, motor and trailer was free.

With what you're going to go through to do that you're still better off going for the whole lower unit.

You might even luck into one that dosnt need seals.

I have more time then cash to spend on it right now, that will be plan B if I fail.

 

[1648grizz]

Well I made a little homemade PF, no hurry to get this prop off so I will keep treating over the winter and maybe get lucky. If no luck by March the grinder it coming out.