Fuel pump getting hot..

[bluegrass]

I have tried to fit new points and diaphragm to my broken fuel pump. It ran ok on the bench, but once fitted, the car had a lower tickover, so must have been getting less fuel. After a few minutes the pump stopped, and was very hot to the touch. Once back on the bench, it runs fine again. Any ideas much appreciated.

[steve jw]

could the earth need cleaning?

[bmcecosse]

It will be hot if it spends a lot of time with the contacts closed - it' supposed to stop (because of output pressure) with the contacts open - then the carb calls for fuel, the diaphragm relaxes, the points close and it pumps again. So I can only suggest you adjust the throw-over stroke to get to that happy state!

[Ufudu]

Sounds like you may have a blockage/restriction on the fuel inlet side, causing it to get stuck in the 'energised' or 'sucking' phase (rather than the de-energised or pushing fuel to the carb phase (if you know what I mean...))

[Biggles1957]

Have you checked the filter?

[bluegrass]

Thanks. I got it working after re-assembling again. The only thing now is that the clicks seem very loud, louder than the electric non points version I had on before. Will it get any quieter with use or could it be another adjustment problem?

On the SU website it states:

(a) Check the lift of the contact blade tip above the top of the pedestal (A) with a feeler gauge, bending the stop finger 'X' beneath the pedestal, if necessary, to obtain a lift of 0.9mm +/- 0.13 mm (0.035 +/- 0.005 in).
(b) Check the gap between rocker finger and coil housing (B) with a feeler gauge bending the stop-finger 'Y', if necessary, to obtain a gap of 2.3 mm +/- 0.13mm (0.090 +/- 0.005 inch).

I notice other people set the (b) gap to 0.070 rather than 0.090 . would that make it any quieter ?

Thanks

[bmcecosse]

Loud is good - you know it's working..... It's when it goes quiet that you start worrying. If it really bothers you - it can be mounted on little rubber 'cotton reel' insulators. Cue Declan for his excellent (and much used) picture.......

[bluegrass]

Ok, thats great. Thanks