Crank nut

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Mar 17, 2013 | 05:42 PM

Nick_R

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From: Iowa

Crank nut

The nut on the end of the crank that holds the sprocket on in the primary on my ironhead backed off on me and screwed up the threads in the nut. The crank looks fine though surprisingly enough. I called the only HD shop open on a Sunday withing 100 mile radius of me today and was told that Harley doesn't make the nut anymore.
Does anyone happen to have an old parts manual around that has the part number in it to maybe help my search or know of another place to possibly get one from? I've searched the net all last night and most of today with no luck.

Mar 17, 2013 | 09:09 PM

IronMick

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From: London, ON Canada

I presume you are asking about your 1972 Sporty?

NUT, sprocket shaft 1970 to 1978 40387-70

http://www.debrix.com/Nut-Sprocket-H.../98-336-mw.htm

http://www.ebay.com/itm/HARLEY-40387...-/160623402710

http://www.ebay.ca/sch/i.html?_trksi...6000&_from=R40

Lots more sources. Put the part number into eBay and Google searches. Looks like they may cost the most on eBay.

You need the Factory Parts Catalog 99451-78B; and the factory service manual 99484-78. Again put the part numbers into eBay and Google searches.

Mar 17, 2013 | 09:52 PM

Nick_R

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Awesome thanks, not sure why I couldn't find anything. I'm not sure that it would make a difference though, those are capped nuts where as mine is a through shot, but it won't reach all the way through anyways.

There is what mine looks like, it's run down finger tight in the pic just to hold everything in place but not torqued down.

Mar 18, 2013 | 06:01 AM

IronMick

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PhotoBucket is not responding right now so i am unable to post a pic of mine. Will do so later.

I do not know but i expect that a PO has replaced yours and the one that you have is not correct.

Also the parts catalog has a "compensating sprocket" for 1967 to E76. There are several associated parts. I have no experience with these parts but i have heard that they are unnecessary and can be removed. Looks like that has been done on yours. Probably that is when the nut was replaced.

That nut requires 100 to 120 ft lbs of torque on install. It should never be installed without a torque wrench. My indie mechanic uses red locktite on it as well.

Mar 18, 2013 | 05:24 PM

Nick_R

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From: Iowa

Yeah it didn't look to have any locktite on it and I going to assume it wasn't properly torqued to begin with, but it will be once i get a new nut.

Mar 18, 2013 | 07:47 PM

IronMick

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From: London, ON Canada

Here's a pic of mine installed. Note that it looks like it is not on completely. Well, it is completely installed. That is how it looks.

Note also the piece of steel stock 4" x 1" x 3/16" to lock the sprockets and chain. Slant it one way for install, the other way for removal ...