Author Topic: A 7 plunger camshaft  (Read 1198 times)

Offline anjimehra

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A 7 plunger camshaft
« on: 09.06. 2017 15:35 »
Hi
Help Please ! Cant seem to get any info on the camshaft end float. Even after fully tightening the gear onto shaft the play still persists. Thanks
Anji

Offline coater87

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Re: A 7 plunger camshaft
« Reply #1 on: 09.06. 2017 16:00 »
Hi Anji,

 That's OK. There is a cork that goes between camshaft gear and breather that will tighten that up.

 Do a search here and it's explained very well how this all goes together, better than I could explain. *conf*

 
Central Wisconsin in the U.S.

Online RichardL

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Re: A 7 plunger camshaft
« Reply #2 on: 09.06. 2017 17:14 »
Anji,

Here is s relevant link: http://www.bsawiki.co.uk/chaps/9-engine/16-chapter08

Here is the paragraph that applies.

The crankcase breather should now be inserted on to the cam pinion, with a cork washer between the pinion and breather. Smear the breather with engine oil, and place the inner cover in position, securing with the screws. Check end float on the breather and correct if necessary by fitting a thicker cork washer.

One more thing. When you buy the breather washer, make sure it is a set with multiple thicknesses to choose from.

Richard L.

Online RichardL

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Re: A 7 plunger camshaft
« Reply #3 on: 09.06. 2017 17:22 »
I guess I have to add one more thing. That paragraph says to correct a bad fit by adding a thicker washer. Obviously, if it's too tight you should be adding a thinner washer not a thicker washer. Don't fracture your inner timing cover by over tightening on a way too thick gasket.

Offline anjimehra

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Re: A 7 plunger camshaft
« Reply #4 on: 09.06. 2017 19:13 »
Hi Anji,

 That's OK. There is a cork that goes between camshaft gear and breather that will tighten that up.

 Do a search here and it's explained very well how this all goes together, better than I could explain. *conf*

Thanks Coater 87. I had visions of having to strip the crankcase again !!

Offline anjimehra

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Re: A 7 plunger camshaft
« Reply #5 on: 09.06. 2017 19:14 »
I guess I have to add one more thing. That paragraph says to correct a bad fit by adding a thicker washer. Obviously, if it's too tight you should be adding a thinner washer not a thicker washer. Don't fracture your inner timing cover by over tightening on a way too thick gasket.

Thanks Richard. To the rescue once again !

Offline chaterlea25

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Re: A 7 plunger camshaft
« Reply #6 on: 09.06. 2017 23:08 »
Hi All,
I hate to rain on your parade BUT  *ex*
When the cam sprocket is bolted fully in position there should be minimum end float
I have seen where  the pinion key gets "hung up" and a piece of it gets squashed between the pinion and camshaft shoulder
resulting in excess endfloat *warn* *warn* *warn*
The purpose of the cork washer is to make the top hat breather air tight *ex*

John
1961 Super Rocket
1963 RGS (ongoing)

Online RichardL

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Re: A 7 plunger camshaft
« Reply #7 on: 10.06. 2017 00:40 »
Bu, bu, but, John, will there not naturally be space there for the cork? Is the BSA service sheet wrong? Maybe I just don't get what you're saying.

Richard L.

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Re: A 7 plunger camshaft
« Reply #8 on: 10.06. 2017 01:16 »
G'day Anji.
Doing a search on the subject I found a post of yours back in 2009 on the Classic Motorcycle Forum.
Once the pinion is on the camshaft it should have 2-3 thou" endfloat. When the cork is compressed by the inner cover there should be no float of either the camshaft and timed breather. The cork should only be thick enough to give 1/2mm compression as too much will cause excessive wear of the outer bush thrust face.
Cheers
'51 A7 plunger, '57 A7SS racer now a A10CR, '78 XT500, '83 CB1100F, 88 HD FXST, 2000 CBR929RR ex Honda Australia Superbike .
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Muskys Plunger A7

Offline chaterlea25

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Re: A 7 plunger camshaft
« Reply #9 on: 11.06. 2017 14:28 »
Hi Muskie,
Absolutely !
I would be hard pressed to get it all into that statement *smile*

John
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Offline bikerboy

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Re: A 7 plunger camshaft
« Reply #10 on: 13.06. 2017 01:01 »
I have to say I have had a fair number of A10's apart and I dont think I have ever had as little as a couple of thou end float on the cam?

Offline anjimehra

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Re: A 7 plunger camshaft
« Reply #11 on: 25.06. 2017 08:00 »
Thanks guys for all your help & advice. Got it all together & fired up the other day. Running abs fine except for noisy valve gear / timing side. Tap pets are correctly set at .010 " & oil going into the rockets from the return pipe, very little backlash in gears, oil pump OK as timing chest has plenty of oil. The breather was assembled w/o end float, but on rechecking has developed some play. I would have thought that the cork washer would expand after getting soaked in oil, but the reverse seems to have happened ?? New cam bushes. Foxed ! Any ideas
Anji

Offline duTch

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Re: A 7 plunger camshaft
« Reply #12 on: 25.06. 2017 10:24 »

 I can't recall if I actually did it, but at least considered 'shimming' the cork with gasket paper-or any suitable material of whatever thickness I needed-BEHIND the cork..if need be......can't see that'd be a problem *dunno*
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
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Offline anjimehra

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Re: A 7 plunger camshaft
« Reply #13 on: 25.06. 2017 14:09 »

 I can't recall if I actually did it, but at least considered 'shimming' the cork with gasket paper-or any suitable material of whatever thickness I needed-BEHIND the cork..if need be......can't see that'd be a problem *dunno*
Hi duTch
Shouldn't the cork have expanded after getting"wet " ? Am going to shim up the washer as suggested, but still can't figure out the source of the clatter in the valve train