SU pump assembly

[alanworland]

Just used a rebuild kit from Burlen on my 70 year old pump. Looking very good inside but the diaphragm had got very 'firm' compared to the new!
The Morris manual suggests powering the diaphragm into operated position before tightening the six assembly screws but the Burlen instructions make no reference to this?
Could this be because the new diaphragm is more flexible and doesn't need it?
Makes sense to power it before nipping up.

Alan

[svenedin]

I have also read that the pump should be powered and the points held closed before the 6 body screws are finally tightened. I think this is old guidance because I have a recent copy of the SU Workshop Manual and there is no mention of powering the pump in the reassembly instructions. As you say, it may be related to changes in the material used for the diaphragm.

If you have used a rebuild kit that contains a Zener diode (that reduces arcing and pitting of the points as well as reducing radio interference) be careful that the diode or its wires are not crushed onto the points when you put the cap on. I am assuming that you are using your old cap which will not have the hump to accommodate the diode. I had trouble getting that diode to sit correctly and the diode's legs are fragile and will snap if fiddled with too much......as I found out.

Stephen