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Odd screw
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Topic: Odd screw (Read 2174 times)
coater87
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Join Date: Jul 2008
Posts: 1204
Karma: 6
Odd screw
«
on:
15.07. 2009 21:31 »
Guys,
I have cleaned up the cases, and was going to shell blast them today. After cleaning them I noticed an odd screw near the timing side bush- I think I remember this being a spring and ball check valve. But I am not sure if my memory is correct here.
Is there good reason to remove this, or maybe it is just an oil gallery plug and should be left alone? I am curious as to whats behind "door #1", but I also believe the screw will not survive this. If I do have to remove it, does anyone know the part number as I cannot find it in my meager "wish books".
Lee
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Central Wisconsin in the U.S.
muskrat
Global Moderator
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Join Date: Jul 2009
Posts: 10777
Karma: 130
Lithgow NSW Oz
Re: Odd screw
«
Reply #1 on:
15.07. 2009 22:19 »
You are correct it is a check valve and it would be a good idea to at least clean it out. I have seen them on eBay (njavery) in UK I recall.
Cheers
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'51 A7 plunger, '57 A7SS racer now a A10CR, '78 XT500, '83 CB1100F, 88 HD FXST, 2000 CBR929RR ex Honda Australia Superbike .
Australia
Muskys Plunger A7
coater87
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Posts: 1204
Karma: 6
Re: Odd screw
«
Reply #2 on:
15.07. 2009 23:38 »
Hi Muskrat, and thanks for the reply.
I found the ball and spring on e-bay alright, so I am set there. I am most worried about the little screw itself- seams mine was peaned over in the same manner as the sludge trap plugs. I dont think there is any way I will get it out and be able to save it. I did not see that part on e-bay, and its not listed in my parts books.
Any thoughts?
Thank you,
Lee
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Central Wisconsin in the U.S.
olev
Brisbane, Australia
Resident Legend
Join Date: Sep 2008
Posts: 624
Karma: 5
Re: Odd screw
«
Reply #3 on:
15.07. 2009 23:40 »
Lee,
Its an interesting one. This is the valve that prevents wet sumping.
I wrecked the bung getting it out of mine but had no problem getting another.
The spring was a different matter, mine was stuffed and in 2 pieces.
The new spring I got from njavery was an mcs brand and looked nothing like the original.
The next one was from the local bike shop (also an mcs) and was very very stiff and nothing like the original.
Maybe both would have worked but this really high lighted to me the variable quality of the spares we buy.
I finally got one I'm happy with from a wild old hairy type at a swap meet. (with a personal guarantee)
The BSA service sheets tell you not to disturb this screw. From where I'm sitting its just as well I ignored their advice.
The later model A65's fitted this valve under the oil pump where its accessable.
Its your call Lee, but unless you have better luck than me, prepare for some fun.
cheers
ps: thanks for the lead on the bottom end , but it all got too hard.
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Dynamo Regulators Mike
A's Good Friend
Join Date: Apr 2008
Posts: 168
Karma: 6
Fareham, UK, 1960 A10
Re: Odd screw
«
Reply #4 on:
16.07. 2009 09:00 »
Hi Coater87
I fully agree with Olev, open the door.
When I took mine out the lightweight spring was in 2 pieces. But a good cleanup and new replacement ball and spring will eliminate most 'wet sumping' or drain down (apart from leaks past oil pump gasket and shaft. And look how many times that issue comes up.
DO take care with getting correct weight replacement. I think I got mine from Draganfly but Lightning spares, C & D for example should also be reliable source. When sorted no need for feed line taps or aftermarket valves.
Cheers
Mike
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Mike Hutchings
A10, T800
Director, DRL
www.dynamoregulators.com
coater87
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Join Date: Jul 2008
Posts: 1204
Karma: 6
Re: Odd screw
«
Reply #5 on:
06.09. 2009 14:43 »
Well guys,
I absolutely destroyed the screw getting it out. I could not believe how deep the peening was, seams someone fifty years ago had an "angry face" on, (thats what my 8 year old daughter calls such moments!
).
Now I need a new screw (or need to know the thread size- as all I have is a bent up lump left)- and a part number for it if possible. I have read on the forum about the A65 valve, but no really good explanations on it. If I go with the A65 set-up, what do I need to modify or do?
My spring was in one piece, and I suppose with a clean-up I could re-use it after grinding the ball in for sound mating. The big one here is the screw. I am willing to make this if I have to, but I need to know all I can about it, or an SRM part number, or any other help. I am stuck in the mud until I get this sorted.
Lee
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Central Wisconsin in the U.S.
scotty
Resident Legend
Join Date: Aug 2008
Posts: 557
Karma: 8
Re: Odd screw
«
Reply #6 on:
06.09. 2009 16:23 »
Lee
you're doing the right thing in replacing the anti syphon assy while she's all laid bare
i recently replaced mine and got the parts from British Cycle Supply in NS canada.
i think they also have a store in hackensack NJ.
here's the part no's
67-1401 oil retaining ball grub screw
67-1400 oil retaining ball spring
1 4675 oil retaining ball
scotty
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Scotty
Current liabilities:
'56 A10 Dark Flash
'54 B33
‘74 Berlin Bomber R75-6
coater87
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Join Date: Jul 2008
Posts: 1204
Karma: 6
Re: Odd screw
«
Reply #7 on:
06.09. 2009 18:08 »
Scotty,
Thanks!!!! That is exactly what I needed to know, and BC is not all that far as shipping goes.
Lee
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Central Wisconsin in the U.S.
olev
Brisbane, Australia
Resident Legend
Join Date: Sep 2008
Posts: 624
Karma: 5
Re: Odd screw
«
Reply #8 on:
07.09. 2009 03:51 »
Lee,
I remember reading somewhere (could have been on this forum) not to grind the ball in with paste.
Its better to sit the ball against its seat and give it a couple of sharp taps with a rod and hammer.
Apparently this does the job admirably.
maybe someone else can comment on this?
the size of my sharp tap might differ to others.
cheers
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RichardL
Outside Chicago, IL
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Join Date: Nov 2007
Posts: 6387
Karma: 55
Re: Odd screw
«
Reply #9 on:
07.09. 2009 04:17 »
Olev,
I confess, I was one (perhaps the only one) to suggest grinding in with paste. I can't say I know it's better than a tap, but, having lapped in a lot of valves, it seems to make sense, to me, at least.
Richard L.
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orabanda
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Join Date: Nov 2008
Posts: 1180
Karma: 24
Re: Odd screw
«
Reply #10 on:
07.09. 2009 11:39 »
Olev,
Youv'e got it right brother!
A light tap, using a drift which is softer than the ball (mild steel or copper is very good). Don't hit the ball excessively hard, as the crankcase is soft (aluminium) and the seat could be damaged.
We use this technique daily in the fluid power industry.
Richard
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Odd screw