Advice for cutting a flywheel off

[Buccaneer]

My harmonic balance puller never failed me either……. until
I tried to pull the flywheel off the RDE-17 25 hp…….. I ended
up adapting an old heavy duty puller into something like the
OMC type, and the flywheel "popped" off the first try.

Prepare to be boarded!

[wetwillie]

I couldn’t agree more about the quality of the OMC puller as compared with any other puller I’ve ever seen. The shouldered bolts are also excellent. However, I snapped those same bolts early on when I used an impact wrench. Thats why I turned to Fastenal to get me a set of shouldered bolts that were even stronger. It was one of those that I had to remove yesterday after it too snapped. Next step is to try heating the flywheel again as hot as I can. I figure I have nothing to lose at this point. I’ll cut my losses and list the motor on CL if I don’t succeed.

[nj-boatbuilder57]

Maybe I don’t know what I’m talking about (quite likely), but it seems to me if the flywheel & shaft are stuck this badly, there’s likely a lot corrosion present. So even if you can get the flywheel off, isn’t it likely that the shaft will be in such poor condition that the engine is doomed anyway?

[garry-in-michigan]

Very likely if the motor was not running when put in storage – but you will never know for sure until the magneto and crankcase half come off to see what can be salvaged . . . 😎

[david-bartlett]

quote NJ-boatbuilder57:

Maybe I don’t know what I’m talking about (quite likely), but it seems to me if the flywheel & shaft are stuck this badly, there’s likely a lot corrosion present. So even if you can get the flywheel off, isn’t it likely that the shaft will be in such poor condition that the engine is doomed anyway?

Actually, I suspect once Willie gets the bugger off, he will find the crank taper to be perfect. That is why it is stuck. A perfect fit with the flywheel to start with has created this situation.

Time to break out a cutting wheel if the impact suggestions posted above don’t work.

[bobw]

Before I’d give up and start cutting, I’d keep at it with some heat and penetrating oils while applying short bursts with the impact gun. Maybe try heating the flywheel good and hot, then hit the crankshaft nut/threads with some CRC Freeze Off to create a temperature difference big enough to pop it loose?

Whatever approach, try not to end up with one that looks like this.

---

Attachments:

Bob

1937 Champion D2C Deluxe Lite Twin
1954 Johnson CD-11
1957 Evinrude Fastwin 18
1958 Johnson QD-19
1958 Johnson FD-12
1959 Johnson QD-20

“Every 20 minute job is only a broken bolt away from a 3-day project.”
"Every time you remove a broken or seized bolt an angel gets his wings."

[jerry-ahrens]

quote WetWillie:

I couldn’t agree more about the quality of the OMC puller as compared with any other puller I’ve ever seen. The shouldered bolts are also excellent. However, I snapped those same bolts early on when I used an impact wrench. Thats why I turned to Fastenal to get me a set of shouldered bolts that were even stronger. It was one of those that I had to remove yesterday after it too snapped. Next step is to try heating the flywheel again as hot as I can. I figure I have nothing to lose at this point. I’ll cut my losses and list the motor on CL if I don’t succeed.

You mentioned that you snapped off one of the shoulder bolts? Were you using them with the OMC puller plate? That’s why I mentioned the part about being careful with the impact wrench.. if the flywheel doesn’t want to pop off after a hit or two with the impact, try a tap with a ball peen hammer centered directly on top off the puller shaft. Do this with tension on the puller.
I have Heli coiled the 3 bolt holes and stepped them up to 3/8 then using the good puller set up, it came right off. You may have to replace the flywheel after doing the Heli coil depending on how well the inserts are installed. If it were me, I would avoid trying to cut it off, as it will most likely ruin the crankshaft. Hope this may be of help!

[wetwillie]

Yes, Jerry, the bolt snapped while using the OMC puller. I snapped one of the bolts that came with the puller, replaced all 3 with stronger bolts from Fastenal and snapped one of them. I also tried the impact gun and whacking the puller center shaft with a hammer while it was under tension. I don’t recall if I snapped one of the bolts while using the impact gun or a breaker bar. Naturally, I’m hoping that, IF I’m successful, that BobW will be correct with regard to the taper.
I’m hoping to take another try at it today. I’ll report back this evening if I do. Stay tuned 😉

[chinewalker]

More often than not, a bolt that has simply broken off can be threaded back out with a pick. It’s not corroded in place, no buggered threads, so it should be loose in there. I’ve succeeded in removing them more often than not, without having to resort to left hand bits or other extreme measures. I snapped a bolt off installing a lower unit a few weeks ago and was able to just back it right out with the tip of a dental pick…

[outbdnut2]

If you use the left or right hand drill bit, drilling into a hardened bolt can be a challenge – I’ve had some success putting my drill into the "Hammer-drill" mode that was intended for masonry bits in cement.
Dave

[Author]

Posts