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Author Topic: A10 valves  (Read 1680 times)
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bsa- bill
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« on: 20.08. 2006 14:04 »

Lapped in the vales on A10 project last night, got a nice matt ring around
each about an 16th inch.
put the springs and collets on and filled the heads with diesel/petrol
mixture.
Checked it this morning, most of the liquid still there  -   maybe one pot
has dropped a sixth and a the other a quarter
slight moistness in one ex port and enough liquid that it can be seen in the
other.
Now my question is - is this acceptable or should there be no leakage at
all, they were left for about twelve hours and diesel/ petrol makes a good
penetrating oil.

All the best - Bill

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All the best - Bill
LJ.
Peterborough UK.
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« Reply #1 on: 20.08. 2006 15:02 »

Well Bill... I'm no engineer or mechanic but it sounds good to me. Diesel or penetrating oil will get through as thats what the stuffs designed to do. I'd be happy with your results.

Incidently I had my valves done by SRM, very happy with what they done. Boy! you could feel the compression afterwards when the head was refitted.

As some BSA friends have said to me... These old bikes are very forgiving! and I think it is very true!
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Ride Safely Lads! LJ.
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1953 BSA B33  500cc Teles/Plunger-Maroon
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1961 BSA A10  650cc Golden Flash-Red
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« Reply #2 on: 20.08. 2006 15:39 »

Now my question is - is this acceptable

Seems -very- acceptable, quite perfect, ain't it?

Erling
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bsa- bill
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« Reply #3 on: 20.08. 2006 18:57 »

Well I hope so Erling, save me getting the valve compressor out again 8)
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All the best - Bill
dpaddock
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« Reply #4 on: 29.09. 2006 01:29 »

Perhaps good enough for roadwork, but . . .
For competition, I do the following:
   Lap the valves, diluting the paste with light oil after every twenty or so rotations.
   Wipe the surfaces with facial tissue until they're clean.
   Drop the valves in and fill the chambers with rubbing alcohol. Do NOT fit the springs or oil the faces.
   Wait a few minutes.
   Check the ports for wetness.
   Repeat the process if leakage shows.
If you can't get a good seal this way, you might have a bent valve stem or an off-center valve guide. Stop and fix the problem.
Remember, the purpose of the valve spring is to follow the cam at all engine speeds: it's not there to seal the valves. That's your job.
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David
'57 Spitfire

a10gf
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« Reply #5 on: 29.09. 2006 01:59 »


Remember, the purpose of the valve spring is to follow the cam at all engine speeds: it's not there to seal the valves. That's your job.

Never tought of it that way, excellent!

Regards
E.
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A10 GF '53, Triumph 900 Legend, Yamaha XT500
Norway - Bergen
bsa- bill
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« Reply #6 on: 08.10. 2006 22:43 »

Well almost finished our busy spell ( overtime working ) so will have more time shortly, so I have started to give this method a go. no intention of competion work but when the heads off might as well go for the best result I can, let you all know how it goes.
Then I have a spitfire camshaft to fit, so once again as the cases are to split might as well have the sludge trap cleaned ( oh joy )
we do have a compressor and air tools on the farm so I'm thinking there is an attachment like a large screwdriver bit, might be usefull for removing the caps --- ah getting ahead of myself .

all the best - Bill
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All the best - Bill
bsa- bill
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« Reply #7 on: 12.11. 2006 19:42 »

Well I used Dpaddocks method to grind in the vavles, did both sides although it needed two goes on the troublesome side to get it them to seal.
used thin fork oil ( it was at hand ), both sides showed no sign of leakage after several days - I'm happy
many thanks for all advise given

all the best - Bill
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All the best - Bill
a10gf
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« Reply #8 on: 12.11. 2006 20:23 »

Hi Bill, about your (former) personal picture...  Tongue You own the cutaway A10 engine? Lucky you if so, any story about it? (start a new thread)

Regards
E.
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A10 GF '53, Triumph 900 Legend, Yamaha XT500
Norway - Bergen
bsa- bill
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« Reply #9 on: 13.11. 2006 11:09 »

Hi Erling - no I don't own the engine just the picture, has not come out as well as I'd hoped ( hence the change )

All the best - Bill
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All the best - Bill
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