# Shaft coupler removal?



## mizlplix (May 1, 2011)

The only good way is with a puller, even if you have to make one.


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## DavidDymaxion (Dec 1, 2008)

I couldn't get mine off with a puller even (puller bent!). I wound up tapping with a hammer for something like 30 minutes.


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## mizlplix (May 1, 2011)

Not to be a smartass, but I am talking about a real puller. Not those auto parts store things. A heavy duty puller consists of a split-plate lower to go around the coupler, two rod columns and an "H" beam strong back with a 1" minimum pusher screw. The end of the screw can be turned or ground down smaller to suit.

And after you have the puller maxed out, apply heat to the coupler. It will come off. If it was installed dry, it is most likely just electrolysis caused oxidation making it difficult.

G/L Miz


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## Ziggythewiz (May 16, 2010)

Thanks for the tips. I may use a combination of all 3 methods. Will post results after it comes off this weekend.


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## DavidDymaxion (Dec 1, 2008)

If there's enough room (between the backside of the coupler and the motor) a bigger puller is great. You also might be able to rig something up to use the flywheel bolts with a big puller. It would be much faster to cut off a cylinder of hard steel (maybe from a socket extension) to drop into the pilot bearing hole, and push against that, than to machine down the hardened tip of a puller (plus it doesn't cut up the tool).

Another trick I have found for friction fit parts is to use an air chisel to get them apart.

Here's another thought -- might a slide hammer work better than a puller? The vibration of hammering something can actually help loosen things.


mizlplix said:


> ... I am talking about a real puller. Not those auto parts store things. A heavy duty puller consists of a split-plate lower to go around the coupler, two rod columns and an "H" beam strong back with a 1" minimum pusher screw. The end of the screw can be turned or ground down smaller to suit.
> 
> And after you have the puller maxed out, slowly apply heat to the coupler. It will come off. If it was installed dry, it is most likely just electrolysis caused oxidation making it difficult.
> 
> G/L Miz


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## mizlplix (May 1, 2011)

A slide hammer is a good idea. It is easy to make and might work well in this instance. 

Only one comment. 

The motor has a thrust washer. They are usually fiber and fragile. A slide hammer will beat these to some extent. Just a thought. The same goes for hammering the hub onto the shaft. Be careful. 

Miz


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## piotrsko (Dec 9, 2007)

I know mizl said this, but it bears repeating:

warm up the hub edges with a propane torch, while being mindful of the extreme torch tip heat. 200 degrees is a good target which would give you about .001 expansion on the center of the hub. then do all the above.


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## steven4601 (Nov 11, 2010)

I did the same for installation of the adapter. (designed it too small on pourpose to create an interference fit.)
http://z3.fiberhosted.nl/index.php?n=Conversion.AdapterDrawings

Torch is easy for installation. For removal you'll need a very powerfull one not to heat up the shaft of the motor. An Induction heater might be a better solution.


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## Ziggythewiz (May 16, 2010)

Ok, here's my late update. It took around 10 hours over 2 weeks to get the coupler to budge 1/4". Efforts involved hammer, mini-sledge, angle irons, 3 gear pullers, a crowbar, and a propane torch. Not sure if the heat ever helped. What did seem to work was a 5 ton gear puller borrowed from auto zone, and with that tourqued up I put a couple angle irons under the coupler wedge-like and whacked it with the mini sledge and it popped up a little.

A little work with the crowbar and I was able to get the coupler up high enough for the big gear puller to mount properly on the bottom, then another 10 hours over a week putting 400 ft lbs on the puller slowly got it off.

If I had to do it again I'd spring for this on day 1, $59 seems a lot for a single use tool, but would have been a bargain.


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## mizlplix (May 1, 2011)

If you read my two above posts, I indicated the type of puller you needed. Big.

I use oxygen/acetlyene for heat. You need to get it up to temp quickly and hot enough to be sub-red. If you dont have access to oxygen/acet. at least get rid of the propane. Get MAP. Home Depot in the Yellow cans (Not blue) It is MUCH hotter.

I am a 60 year old professional mechanic. I know stubborn equipment. 

Chin up, you have it now... : )


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## Ziggythewiz (May 16, 2010)

I knew it would take a big one, but I didn't expect to brake multiple 1 ton pullers. I don't really know how that's calculated, but I can't imagine I could put a ton of force on it with just hand tools. Puller bored into the end of the motor shaft over 1/4"

New coupler's on though and car's back on the road after nearly a month's hiatus


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## piotrsko (Dec 9, 2007)

pullers are somewhat calculated by what style puller they can replace. a 1 ton means it replaces a 1 ton screw jack press, which if you ever saw one isn't really all that big or powerful. It also uses a 18" long bar as the primary force application so maybe on a good day you can get to a ton of force applied over a 1/8 diameter rivet which would mean about 500 psi.


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