Stuck Flywheel

[m casey stock]

I've been trying to change the flywheel on my little 88 Johnson 25hp to an electric start flywheel with the ring gear. Can't get the original one off. Any tricks you guys can think of? I've soaked the shaft with BP Blaster for a week and bumped the end of my puller with a hammer and it will not budge. I was told not to use heat due to the electronics under and around the flywheel.

 

[boobie]

Re: Stuck Flywheel

Take a big screwdriver or pry bar and lay it in on the block and pry up on the flywheel only. Then rap your puller bolt. Rotate the flywheel 180* and try it again. Make sure your puller bolt is good and tight.

 

[m casey stock]

Re: Stuck Flywheel

Take a big screwdriver or pry bar and lay it in on the block and pry up on the flywheel only. Then rap your puller bolt. Rotate the flywheel 180* and try it again. Make sure your puller bolt is good and tight.

Okay, tried that today, still no luck I'm not to worried about trashing the old flywheel, what if I drilled some holes close to the shaft and tried to crack it with a chisel? Has anyone on here tried something like that? I don't want to damage the motor, at least it runs right now LOL and could be sold to someone who didn't mind a pull start.

 

[m casey stock]

Re: Stuck Flywheel

Okay, finally got it! WooHoo!!! after braking several 1/4" bolts I drilled out the holes and re-tapped to 5/16" I was then able to put full force of my 1/2" drive impact wrench on the puller and tap the edges of the flywheel, just hard enough to "ring it's bell" with all this pressure applied and it finally popped loose! Electric start coming soon

 

[gm280]

Re: Stuck Flywheel

Although they (some on these boating pages) say not to use a pneumatic impact wrench on the flywheel puller setup, that was the only way I could remove mine as well. So I'll risk the chances of breaking something verses not being able to remove the flywheel every time now. I also broke a few 1/4 X 20 bolts before I purchased some grade 8 types. They did the trick... Glad yours is off now. Hope your conversion goes well without any more problems... Post your results alone the way with plenty of picture for others to see your progress.

 

[seahorse5]

Re: Stuck Flywheel

Using an impact wrench on the factory or a heavy duty puller to remove a tight flywheel is healthier for the crank and bottom ball bearing than when you hit the puller screw with a large hammer. The full force of that blow is taken up by the crankshaft journals and the ball-bearing that handles the thrust of the crank. In some cases where the bearing is not shattered, the balls and the race have small flat spots that will cause a noisy bearing or an outright failure over time.

 

[m casey stock]

Re: Stuck Flywheel

I had read about the possible bearing and thrust washer damage, and pray that me being as cautious as possible with my "rapping" of the puller bolt did not damage anything. I used grade 8 bolts in the original sized 1/4" 20 flywheel holes and there was so much pressure on the puller that each time a bolt broke it shot feet into the air across the shop LOL After I drilled the holes out to 5/16" 18 holes the pressure was so great that I actually wrapped the puller with a fender cover because I got so nervous about where the pieces would fly and what damage would be caused if something broke. I used an Ingersoll Rand 1000 lb. impact and still almost ran out of impact before it finally let loose, and then only after rapping the flywheel around the outer edge. When you have one with defective electronics and the motor wont run, what choice do you have? In my case, the motor ran fine, I just wanted electric start, so I guess I could have sold it and found another one that already had electric start. You know how it is, you start on something and it almost becomes a quest to see it through. Crazy to be on there that tight, but I understand if it is not then you risk shearing the key and spinning the flywheel and possibly damaging the crank. Anyway, I did run the motor after this and it sounded fine, but only time will tell if the bearing rollers have flat spots, hopefully not.