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Author Topic: Camshaft end play  (Read 248 times)
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Ron B
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« on: 28.09. 2011 15:07 »

Hi everyone, on my A10 crankcase (no number vintage unknown) I am having a bit of a problem setting up a 356  cam.  If I put the cam pinion on the cam as far as it will go it is bound up against the crankcase and will not turn.  So by pulling the pinion off a bit I am able to rotate the cam.  The problem by setting the cam pinion this way I have arrived at a random position of the cam in the crankcase and it is locked into place only by the press fit of the pinion on the cam and the piece of cork.  How do I set it up so that it is correctly located in the crankcase?  It looks like the bushes in the crankcase are a longer distance than the drive end bearing surface of the cam.  Any advice will be appreciated.  Ron Bohm
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1949 A7 Long Stroke
1950 B31 w/ M21 engine
1954 A10
1967 BMW R60/2
muskrat
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Lake Conjola NSW Oz


« Reply #1 on: 28.09. 2011 15:32 »

G'day Ron,
              is the key staying in place when you push the pinion on ? They can slip back and wedge against the bush. The pinion is a snug fit so I heat it up and use a glove to push it on easier. Also use a soft (wood or plastic) wedge between the cam lobe and case to stop the shaft moving inwards.
 Cheers
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Only young once, immature forever. Now how can I make this go faster. '51 A7 plunger, '57 A7SS now A10, '71 A65 Lightning (gone to god) '76 XT500, '83 CB1100F, next project a '64 A65.
chaterlea25
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« Reply #2 on: 28.09. 2011 16:24 »

Hi Ron,
Further to Muskrats observations,
Are the cam bushes fully home in the cases?
The cam position is held by the pinion locking against the shoulder on the cam.
the distance between the cam gear and the shoulder on the camshaft (pinion fitted) should
be a few thou greater than the width of the cam bush on the timing side case
So it looks as if you have some mismatched parts???
THe cam MUST sit correctly so it will match the followers
some measuring will tell you if the bush inner or outer needs machining
Make sure the inner face of the cam pinion has not been damaged by the shoulder on the cam

HTH
John O R
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1961 Super Rocket
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bsa- bill
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« Reply #3 on: 28.09. 2011 20:26 »

Hi Ron
I've had that trouble and it was as John states the new bushes, the shoulders was to thick.
took a bit of careful measuring and machined a bit off the shoulders (machined - in the loosest meaning of the word  smiley4)
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All the best - Bill
Goldy
Warwickshire, England
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« Reply #4 on: 28.09. 2011 20:33 »

Yes spot on Bill the dimensions of replacement parts are not very accurate and I assume the manufacturer does not realise the importance of the flange thickness.
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56 A10 Golden Flash - Restore, ride, relive.                                           
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Ron B
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« Reply #5 on: 29.09. 2011 02:32 »

Thank you all for the information.  I suspect the bushes are the problem.  This engine is built out of the junk box.  Heaven knows what else I will find in there.  If my information is correct the span of the bushes is 2.485-2.498.  Should have checked.
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1949 A7 Long Stroke
1950 B31 w/ M21 engine
1954 A10
1967 BMW R60/2
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