Author Topic: MK idler spindle  (Read 430 times)

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Offline tck

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MK idler spindle
« on: 27 Nov 2020 at 11:14 »
In the timing side of the crankcase casting of the MK  there are two hollow idler spindles that support the idlers on a bush 20589 they have a hexagon 'boss' on the inside of the crankcase my  top spindle is snapped off at the top of the bush so I have to replace it How are they fixed in the crankcase, screwed, pressed or cast in?
Then I shall have to make a new one in a decent steel

Offline eddie

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Re: MK idler spindle
« Reply #1 on: 27 Nov 2020 at 14:59 »
Hi Tim,
           They are a light press fit in the crankcase.

   Regards,
                   Eddie.

Offline tck

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Re: MK idler spindle
« Reply #2 on: 27 Nov 2020 at 16:40 »
Thanks Eddie
And the LDMCC has them in stock :-)

Offline tck

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Re: MK idler spindle
« Reply #3 on: 30 Nov 2020 at 13:16 »
I have received my replacement spindle (The new post war spares service deserves a round of applause)  Like a lot of things on this engine the broken upper spindle and the lower one  is unlike the replacement  is partially hollow in that a hole has been drilled up the center by eye about 3/16 diameter it is made from both ends but does not meet in the middle there are no cross holes apart from the threaded one and as far as i can see can only be to reduce weight! in fact its hollowness is probably the reason the threaded end had broken off.
My question is have I got another plus part in my engine? was this a know modification  I remind you the engine was originally in the care of the Mcandless brothers in Norther Ireland they of the feather bed Norton  fame
 

Offline tck

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Re: MK idler spindle
« Reply #4 on: 30 Nov 2020 at 16:08 »
To make things a little clearer here is a picture new and broken spindle

Offline eddie

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Re: MK idler spindle
« Reply #5 on: 30 Nov 2020 at 16:56 »
That spindle has fractured immediately below the nut, so I would think it has probably been over-tightened (maybe in order to fit the split pin). In the past, I have skimmed the base of the slotted nut in order to fit the pin whilst getting a reasonable torque on the nut.

Regards,
                Eddie.

Offline tck

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Re: MK idler spindle
« Reply #6 on: 30 Nov 2020 at 20:10 »
Yes I agree but it has not been helped by being centrally drilled I was wondering whether that drilling was a modification by the factory for some models and why it was done considering there was a long hole from both ends with out meeting in the middle

 

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