TheSamba.com :: View topic

Thu Jul 22, 2010 1:22 pm

Couple quick questions regarding my wbx 1.9 crank.

How do you remove the woodruff keys?

Will a crankshaft gear removal tool sold for aircooleds work? Should the gears be heated before being pressed off?

Thanks

Thu Jul 22, 2010 9:25 pm

klucz wrote: Couple quick questions regarding my wbx 1.9 crank.

How do you remove the woodruff keys?

Will a crankshaft gear removal tool sold for aircooleds work? Should the gears be heated before being pressed off?

Thanks

Yes, the gear removel tool for air cooled Type1s also works on the WBX crank. You can also use a hydraulic press, but it has to be a fairly large one so the crank can drop through the table sides. You shouldn't heat the gears up during removal. You do need to heat the gears up to put them back on after installing the new bearing, though.

The woodruff key can be pulled out carefully using vice grips, but you don't really need to remove it.

David

Thu Jul 22, 2010 11:04 pm

If you are sending your crank in for inspection and possible machine work, just let the machine shop deal with removing the gears. The gears come heat treated, you would not want to ever heat them hot enough to affect the heat treatment. You just want to heat them enough to make them go together easy.

Fri Jul 23, 2010 12:54 am

I had read contradicting info about whether or not to heat the gears during removal in other forums. So it's good to hear about it from you guys. Thank you very much for the replies.

Fri Jul 23, 2010 7:45 am

Heating the gears doesn't help with removal because you can't heat the gears only, the heat passes into the crank nose and they expand together, so you don't get the differential expansion that makes the gears' ID grow larger than the crank's OD (basic logic will give you answers, and the right ones, faster and more accurately than self-appointed "experts" on forums; use your noggin'!). Heating doesn't make them harder to pull, it just doesn't make it easier. The exception is when they are really stuck on there due to varnish, heat can soften the varnish at least, and can help some lube penetrate the area. But when they're a bear to get off, they're a big bad bear.

The regular Type1 gear puller also fits the wbx cranks, as David confirmed. The thin lip that grabs behind the steel gear can bend if the gears are really frozen on, though, so if you're having to use an excessive amount of torque and the gears aren't budging, it's time to move it to the press stand to avoid damaging the special tool.

There are two techniques to getting woodruff keys out: tap at one end of the key with a drift no wider than the key, and it will rotate in its notch until you can pluck it out more easily. To grab them, I use a big set of dykes to grab the key while I pry with the jaws against the crank, you can lever it out that way. The dykes may raise a small burr on the cheeks of the key, just file that flat if necessary.

It's best to strip a crank completely if you're dropping it off at the machinist for grinding, that is if you want to be sure to get all your parts back, unless you're specifically asking them to assemble the bearing and gears for you. Busy machine shops are pretty good at misplacing small parts (be sure to knock the felt ring retainer out of your flywheel for this reason, or you'll never see it again). The small key needs to come out to remove the o-ring, the disc behind it, and the #4 bearing just so you can get at the gears, so knock that out at home so it isn't lost. The big key can normally be left in, it isn't going to fall out and it doesn't need to be removed to grind the crank, same goes for the roll pin on the flywheel end, but if you want to be absolutely certain these parts aren't lost, strip the crank down and keep them all safe at home.

Fri Jul 23, 2010 11:26 am

Thanks for all the great info, 10cent. The details you included help me a lot. I promise to use my noggin' more.