Rebuilt my pump recently and replaced some original parts which included the valve discs from Burlen. The new one's appeared to have a shot blasted look to them or possibly they had been deburred in a rumbler type machine?
This gives a slightly broken surface to the discs.
The pump works well but will occasionally tick engine not running!) indicating lost pressure, my carbs have the 'rubber' type seatings and seal positively so the only 'leak' can be back through the valves. Removing them and sucking the valve shut confirms the lost pressure is through the valve/seat.
My original valve discs were smooth finished and therefore would provide a better seal, has anyone else found this?
I'm tempted to polish the surface flat!
Alan
SU pump valve discs
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alanworland
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philthehill
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Re: SU pump valve discs
The Burlen fuels web site technical instructions for SU fuel pumps as fitted to the Morris Minor states that the disc valve has a smooth face and a not smooth face. The smooth face should always face to valve seat.
Does your disc valve have smooth and non smooth faces?
As the valve is a flat disc on a metal/plastic valve seat you will always get some suck/blow/creep past of fuel. The valves are not precision ground.
So long as the fuel pump is delivering sufficient fuel I would leave well alone.
Does your disc valve have smooth and non smooth faces?
As the valve is a flat disc on a metal/plastic valve seat you will always get some suck/blow/creep past of fuel. The valves are not precision ground.
So long as the fuel pump is delivering sufficient fuel I would leave well alone.
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svenedin
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Re: SU pump valve discs
The last discs I fitted (about 8 months ago) had a hatched side and a smooth side. It was very obvious which side was the valve facing side.
1969 1098cc Convertible “Xavier” which I have owned since 1989.
Stephen
Stephen
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oliver90owner
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Re: SU pump valve discs
The pump works well but will occasionally tick engine not running!) indicating lost pressure,
A good reminder to turn off the ignition switch! That might prevent the coil over-heating.
I expect they all tick occasionally. Problems arise when they either never tick or do so continuously (rapidly).
A good reminder to turn off the ignition switch! That might prevent the coil over-heating.
I expect they all tick occasionally. Problems arise when they either never tick or do so continuously (rapidly).
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alanworland
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Re: SU pump valve discs
Thanks for your replies!
Don't remember reading anything about a particular side to face the seat, in fact both sides look identical and appear as though they have been rumble deburred which has left a less than smooth surface.
Not a big deal I know but could have been avoided if (as others have found) one side was more suitably finished.
Alan
Don't remember reading anything about a particular side to face the seat, in fact both sides look identical and appear as though they have been rumble deburred which has left a less than smooth surface.
Not a big deal I know but could have been avoided if (as others have found) one side was more suitably finished.
Alan
