1963 Johnson 40HP Flywheel

[Murf247]

I have a 1963 Johnson 40 HP (RD-25) and I need to remove the flywheel to gain access to the ignition. I have tried for three weeks to get the flywheel off.....soaked in PB Blaster, used a harmonic puller w/hammer and impact driver, I have even talked nice to it. The flywheel is still stuck on there.

I have a donor motor (I need the electric stater motor and fuel pump) from 1961 (RDS-23). Does anyone who if the flywheel is interchangeable? I have noticed the flywheel nut on the '61 donor is smaller, but the top of flywheel tapper looks the same size.

Any advice on how to get the old flywheel, if they are interchangable, or where to get the right flywheel would be helpful.

Thanks!

 

[F_R]

Re: 1963 Johnson 40HP Flywheel

I have a 1963 Johnson 40 HP (RD-25) and I need to remove the flywheel to gain access to the ignition. I have tried for three weeks to get the flywheel off.....soaked in PB Blaster, used a harmonic puller w/hammer and impact driver, I have even talked nice to it. The flywheel is still stuck on there.

I have a donor motor (I need the electric stater motor and fuel pump) from 1961 (RDS-23). Does anyone who if the flywheel is interchangeable? I have noticed the flywheel nut on the '61 donor is smaller, but the top of flywheel tapper looks the same size.

Any advice on how to get the old flywheel, if they are interchangable, or where to get the right flywheel would be helpful.

Thanks!

Flywheel/crankshaft tapers are different size.

 

[Murf247]

Re: 1963 Johnson 40HP Flywheel

Any ideas on removing old flywheel or where to get a different one?

 

[R.Johnson]

Re: 1963 Johnson 40HP Flywheel

On those early forty horse engine, they stessed cleaning the crank, and flywheel taper's before putting back on. Back then carbon tetrachloride was readily available, and most shop's had some. When that was used, it was like the crank, and wheel were welded together. Later there was an OMC bulletin not to use this. I can recall, if using the proper OMC puller, and bolts, pulling the flywheel right off it's steel center core. The center core had to be split with a hacksaw to remove from crankshaft. I have an old forty right now in my scrap heap with the steel flywheel core stuck to the crankshaft. This is not a fun job. Carbon tet, by the way will pull the grease, or oil out of just about anything.

 

[tx1961whaler]

Re: 1963 Johnson 40HP Flywheel

Any ideas on removing old flywheel or where to get a different one?

Soak with 50 - 50 mix of automatic transmission fluid and acetone. Keep off of the paint, and away from flames.

 

[Murf247]

Re: 1963 Johnson 40HP Flywheel

Thanks for the help. I was finally able to get the flywheel off yesterday.....I jept soaking it in the mixture you said.....it worked.

 

[coolguy147]

Re: 1963 Johnson 40HP Flywheel

when putting back on make sure to clean all oil off and torque to proper torque

 

[tx1961whaler]

Re: 1963 Johnson 40HP Flywheel

Thanks for the help. I was finally able to get the flywheel off yesterday.....I jept soaking it in the mixture you said.....it worked.

Great to hear. That's the best penetrant mix that I've ever used.

 

[Rodneys]

Re: 1963 Johnson 40HP Flywheel

50 - 50 mix of automatic transmission fluid and acetone, Mmmm.. I'll have to try that !!

 

[nworkman]

Re: 1963 Johnson 40HP Flywheel

Soak with 50 - 50 mix of automatic transmission fluid and acetone. Keep off of the paint, and away from flames.

I too have a 63 40 HP Johnson RD 25. Have also been trying for a week to get the flywheel off. I was thrilled to read about the auto trans fluid and acetone. Unfortunately the flywheel is still firmly attached. I used a torch to heat the crankshaft. Hope this didn't do harm. Any other ideas? Hope you can help.

 

[nworkman]

Re: 1963 Johnson 40HP Flywheel

Soak with 50 - 50 mix of automatic transmission fluid and acetone. Keep off of the paint, and away from flames.

I too have the same motor and the same problem. I heated the crank with a torch. Hope I didn't do harm. Any other ideas for removing?

 

[tx1961whaler]

Re: 1963 Johnson 40HP Flywheel

If the heating and soaking didn't help, and the puller is tightened up as much as you can get it, then try rapping the center bolt of the puller, but be careful that you don't damage any bearings. That is the top of the crankshaft. I have also tapped "up" from the underside of the flywheel, but you have to be careful not to damage anything.

 

[kenmyfam]

Re: 1963 Johnson 40HP Flywheel

It may take a while to remove but all the above advice given is useful. You will get there in the end. Soaking the release fluid for a day or 2 and keeping adding to it every couple of hours has good success in my experience. Acetone is a great tool to have on hand for many different jobs.

 

[Murf247]

Re: 1963 Johnson 40HP Flywheel

The acetone and trans fluid did the trick for me. I soaked the flywheel for about two weeks in the mixture. I kept adding the mix to the flywheel everyday. I tried to pull it off every third day (use the rapping the center pulling bolt method). Then one the day it did come off I was so mad because I hit the puller and all the flywheel bolts went loose.........just as they had three time prior when the puller broke. Though I broke the forth puller, but I did not the flywheel came off. Then I was very happy...............

I got the engine started after replacing coils/points/conds. By the way I had a donor motor that ran in the early spring so I swapped the carb and fuel pump and added the electric starter motor. Now I noticed the no water is coming through the thermostat housing.................My current job is to rebuild the water pump and ensure all the water passages are not blocked.

Good luck with the flywheel.........give it time, it will come off. One more thing to check. Clean all the fluid off the top of your drive shaft and flywheel. With a bright flash light look at the flywheel and crack shaft to ensure the key ways are lined up. Breaking the flywheel key is a common thing are can cause the flywheel to stick the the shaft. If the motor was running before you started to remove the flywheel, I do not think this would be a problem.

Give it time, it will come off.
Murf

 

[nworkman]

Re: 1963 Johnson 40HP Flywheel

Thank you so much for your reply, Murf. We were ready to give up until you counselled us to keep going. Will let you know how it finally turns out. Great column. Sorry for the double post.

 

[davemaxi1970]

Re: 1963 Johnson 40HP Flywheel

I bought a scrap 1963 johnstone 40hp and wanted the toothed flywheel for my 33hp ski- twin. Used a crowbar under the flywheel at the head to lift it slighty then hit the nut (partially unscrewed) with a hammer and it popped straight off no probs. to the purists this may be a brutal solution but no damage was done and it was a scrap engine anyway. good luck

 

[jimmbo]

Re: 1963 Johnson 40HP Flywheel

My Dad had a 1963 Johnstone Seahorse about 35-40 years ago I remember having the Flywheel come off the engine at full throttle in 1974. Fortunately the recoil starter kept it from clearing the taper and the exiting thru the cowl. So make sure you clean the tapers and torque the flywheel nut to spec which is 100 - 105 ft lb

 

[jay_merrill]

Re: 1963 Johnson 40HP Flywheel

I have a 33hp Johnson that is fighting me now - I think I might have to mix up some of that ATF/Acetone "brew!"