That's my new motto for life: Heat. Beat. Repeat.The process I use to get tapered sprockets loose from hydraulic motors as well as stump grinder wheel hubs from gearbox shafts is as follows:
Hydraulic puller, cheapo 10 ton type. Dog it down on the hub and get it under heavy tension. Apply heat to inner hub around shift. As you heat, keep upping the pressure. Once pressure seems critical, take a heavy hammer and a chunky brass punch and hit where the hub fits to shift. Hit HAAAARD. Stand to the side as the release will normally be violent.
This works on grinder hubs that are torqued to around 550 ft/lbs from factory and haven't moved in 20 years of rust and wood chips.
In the end, it always boils down to:HEAT, BEAT, REPEAT. If it doesn't budge, heat hotter, hit harder.
Yes, it is. I'm halfway there, but I can't see how to continue pursuing that route without damaging the crank shaft.The guys over at Happy-Trails once used an angle Grinder to grind thru a center-hub at the woodruff key slot to remove a stuck flywheel.
Thats a lot of grinding!
I agree with you. If the crankshaft and or bearings aren’t already toast then don’t do that. All that hammering can bend the crank if you hit it too hard. A small right angle grinder with a slitting/cut-off wheel used carefully is a piece of cake. If necessary, cut more than one slot as close as possible to the crank. If you place them 180 degrees apart it will fall off. Or, when your slot(s) is close to the crank try carefully driving a chisel into the slot to separate it. I’ve done it. It works.Rather than heating and beating harder and possibly damaging the crank bearings (if you haven’t already) I’d grind/cut the flywheel off. It’s toast anyway, so sacrifice it and not your crank. A small nick in the end of the crank from grinding won’t hurt anything.
If you are careful and go slowly you won’t have to cut all the way through, just get really close…maybe finish with a dremmel or rotary die grinder.Hmm...food for thought. Now you've got me re-thinking the whole approach. I'm busy the next bunch of days, but I'll get back to the garage after that, armed with some kind of plan, and I'll post an update then.
Patience is key here. No need to rush. If you’re nervous about getting too close to the crank just cut most of the material away and you’ll relieve it’s ability to “squeeze” the crank. Stop and retry the puller. Just don’t beat on it. If it doesn’t release just cut a little more. Lather rinse repeat.Another one of Murphy’s corollaries: when you need to take something apart fast, that’s when it’s most likely to seize.
any progress to report?I had a few hours over the weekend, so I gave it another shot, focusing on the idea of cutting away material from the central hub of the flywheel.
1) Cut away material; cut slits into remaining hub material.
2) Cut two slots on opposite sides to fit a two-leg gear puller (like the pic attached).
3) Heated the flywheel hub with a torch.
4) Cranked on the puller
5) Applied solid, but not excessive, hammer blows to a cold chisel directed into the cuts I made on the hub of the flywheel
Result: the puller tore out the slots I cut into the flywheel, nothing moved. But there's no longer enough material to use the two-leg puller.
I just started cutting away more material. Hopefully I can manage to get the angle-grinder in there enough to eventually just cut it right off.
I should not be allowed to own tools.