Author Topic: Priamary chain adjuster  (Read 117 times)

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Boneidle

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Priamary chain adjuster
« on: 13 July, 2018, 14:36:39 »
Have a 71 Thunderbolt. Oil was leaking from the adjuster. on strip down i found the lock nut & sealing ring were  missing. Ordered  Lock nut part no 68 0237. It will not screw on it's too big across the flats and traps on the frame. The nut size is 7/16 BSF. The parts book says the size is correct. Has anyone had a similar problem or know a solution. My lack of engineering skill's stop me reaching fora file.   Thank's

Editor

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Re: Priamary chain adjuster
« Reply #1 on: 13 July, 2018, 17:28:07 »
That's a really annoying problem caused by the OIF frame designer not considering all the clearances at the time! Its really frustrating.
The best solution I have found so far, is to sort it out when the primary chain is out of the way during a clutch stripdown. Take the bolt out and when screwing it back in, place the seal and a very thin locknut under the chaincase to 'catch' as the screw goes down. It's permanent until the next stripdown so I use a Dowty Seal. It still doesnt seal all that well, but without, it leaks out.
The alternative without stripping down is to file a big flat on a Dowty washer and file down so it will just pass the frame tube. Then make a special 'long' nut from hex bar, turning a portion to a diameter that will allow the nut to pass the frame tube, but short enough that you can grip the flats on the screw to hold in place whilst tightening the locknut - and leave enough exposed thread so the end cap and a seal can be fitted.
Unless someone knows a better/easier solution of course......
Chris
« Last Edit: 13 July, 2018, 22:06:13 by DEE »

Boneidle

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Re: Priamary chain adjuster
« Reply #2 on: 13 July, 2018, 22:26:25 »
Thank's for the advice. The guy I bought it off said it was a two minute Job. Hey Ho. I'll start looking on ebay for a lathe & milling  machine.