MK1 primary (?) knock I can't nail

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paul.jameson
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Re: MK1 primary (?) knock I can't nail

Postby paul.jameson » Tue May 05, 2020 8:28 pm

My money is on coupling gears loose on the shafts.

Take the cush drive off and put an adjustable spanner on the splines of the rear crank. Take the cover off the timing side end of the front crank and apply a suitable spanner or socket to the nut. If you can feel movement between these two spanners, your coupling gear(s) are loose on the shaft(s).

To recify, take off the coupling gear, clean the shaft and hole in the coupling gear and put back on with a smear of Loctite 641. This will solve the problem but next time you need to take the coupling gears off you will need to heat up the centre before applying the puller so as to get the Loctite up to its melting point.
Paul Jameson
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Former Machine Registrar & Archivist, General Secretary and Single Spares Organiser (over a 25 year period).
Now Archivist once more - but not Machine Registrar.

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Re: MK1 primary (?) knock I can't nail

Postby camstevens » Tue May 05, 2020 9:30 pm

Thanks Paul
I'm heading to the workshop tomorrow, and will try this.

Thanks
Cam

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Re: MK1 primary (?) knock I can't nail

Postby camstevens » Wed May 06, 2020 4:51 pm

Hi All
I massively appreciate the suggestions, most of which will almost certainly come into play sooner than later.....but thankfully I found, isolated, and removed the knocking cause. Within the clutch;

It was (see pic attached) caused by some excessive protrusions from the clutch spring studs behind the clutch centre. In the pic I had already filed them down by around 0.035" each! These protrusions were at times lining up with the drum bolt heads, as there was clearance I had assumed they would not contact.. This would have been the case, but I sadly didn't consider the clutch drum wobble, which evidently was enough for them to whack together. (In my defense, I had seen this as a potential cause way way back, and I worked out the clearance between the two studs and deemed them to be too far apart to make contact). My emotions are a mix of feeling somewhat sheepish (should it have been obvoious? :oops:) and great joy :D .

A big takeaway for me is how tricky isolating a noise can be around aluminium casings.....the noise just seems to be everywhere.....like magpies calling....you just don't know where they are!

Cheers
Campbell

Clutch centre.jpg

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simon.holyfield
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Re: MK1 primary (?) knock I can't nail

Postby simon.holyfield » Wed May 06, 2020 5:20 pm

Brilliant! Another one for the knowledge bank. We can all share your relief - I bet we have all been there at one time or another.

A thought. I am currently writing a W/NG magazine article, and while writing about my W/NG experience it struck me that coming to the single from the SQ4 I have never worried much about the single. Having a SQ4 makes you quite resilient, I reckon.
cheers

Simes

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'58 Huntmaster,
'42 W/NG,
'78 CX500
http://ariel-square-four.blogspot.com

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Re: MK1 primary (?) knock I can't nail

Postby Steven.Carter » Wed May 06, 2020 5:41 pm

Well done Campbell.

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Re: MK1 primary (?) knock I can't nail

Postby JohnnyBeckett » Wed May 06, 2020 6:03 pm

HI that is something to go in my memory bank in case i get a noise like that i will look at the clutch first :D :D

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Re: MK1 primary (?) knock I can't nail

Postby john.mitchell » Wed May 06, 2020 11:17 pm

I hope the article is coming to Cheval, Simon.
John
John Mitchell
Editor Cheval de Fer

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Re: MK1 primary (?) knock I can't nail

Postby simon.holyfield » Wed May 06, 2020 11:20 pm

john.mitchell wrote:I hope the article is coming to Cheval, Simon.
John


Of course!
cheers

Simes

'51 Square Four,
'58 Huntmaster,
'42 W/NG,
'78 CX500
http://ariel-square-four.blogspot.com

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Re: MK1 primary (?) knock I can't nail

Postby ryszard.pisula » Sun May 10, 2020 12:29 pm

Hi!

My wife is sending you this reply as we are currently apart and she is not returning home until next week.

I had the same trouble as it sounded like the big end, but it wasn't. If you would like to give me a ring on 01279 413705 and discuss your problem, I am in all day, and I have solved my problem.

Regards

Richard

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Re: MK1 primary (?) knock I can't nail

Postby camstevens » Sun May 10, 2020 12:35 pm

Hi
Certainly keen to hear your experience / solution.

Campbell


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