BSA b44/50

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Like the Norton gear pump the BSA one leaks from feed side to scavenge side via the shafts, I do the same mod as my Norton pump fix and add X rings to the shafts.

X-ring-to-pump.jpg



Plus you need to check the pump assembly as it can leak at the joints and the face where it sits against the crankcase.
 
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In my innocent days of youth (!) I commuted for four years on a B44, and whilst I did do top end work in pursuit of what I now believe to be the mythical: '90+mph' performance figures, the bottom end (apart from the gearbox) remained unmolested and totally oil tight and trouble free.....
 
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Thanks for the answers, seems I have another winter job. Will also check the ball in the return suction pipe, which might prevent leakage between feed and return side of the pump going down to the sump. Luckily have a new spare pump.
 
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Will also check the ball in the return suction pipe, which might prevent leakage between feed and return side of the pump going down to the sump.
No, all that does is stop the oil that was on its way back to the tank held in the pipe from draining back, a egg cupful at most.
 

baz

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I think I may have found the problem
I took the outer timing cover off to access the anti wet sump ball and spring and realised I had the wrong blanking bolt that retains the spring against the ball bearing
It didn't quite meet the spring
I went and found a spare inner timing case that had the correct bolt and it was approximately 3mm longer
So I have re seated a new ball bearing and fitted the correct bolt
Put it back together and started it a couple of times to let the oil level settle
I've checked the oil level in the tank and I'll check again in 3 days
If there is no improvement I shall remove the oil pump and check it
Cheers
 

baz

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Definitely had the wrong length bolt compressing the spring on the ball bearing
I've been starting the bike every day so I haven't been able to give the wet sumping a fair appraisal
But I'm now away from the bike for over a week and I measured the exact height of the oil in the tank before I left
Fingers crossed
Cheers
 
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Presume the bolt is same as on earlier models. A screw 3/8 x 26 with a screwdriver slot. Intended to go in so it's flush with the case. Punched to lock.
What is the correct length of that bolt? Or rather how long shall it go in? No hurry to get an answer.
 

baz

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Presume the bolt is same as on earlier models. A screw 3/8 x 26 with a screwdriver slot. Intended to go in so it's flush with the case. Punched to lock.
What is the correct length of that bolt? Or rather how long shall it go in? No hurry to get an answer.
Yes it's the same one
I don't have the measurement for you but it should compress the spring by approximately 3mm
Or at least it does on my bike
I've just checked the oil level in the tank after one week and it's stayed exactly the same as when I left it, so it was definitely the spring length that was the issue
I should add that I changed the ball bearing (1/4") for a 6mm one
In the hope it would seat better on a slightly different part of the hole
I gave it a sharp tap with a parallel pin punch and hammer to make sure that it seated properly
Cheers
 
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