Fuel pump overheating

[crankedup]

I have a 12v SU fuel pump on my post war classic car. Yesterday I had problems with the car engine spluttering and finally dying out. I found that the external fuel pump body was quite hot to touch. When the pump cooled off the engine started and ran nicely for a few miles until the same problem re-occurred. This happened numerous times on my journey home. The pump ran noisily and seemed to be permanently and rapidly running when the initial break down occurred. After cooling down a little no more rapid runnin* noises.
mystery to me what could cause this? It sure wether to have the pump repaired or replace with new. Advise sought please.

Edited by crankedup on Friday 9th April 10:51

[tapkaJohnD]

Fuel pumps are cooled by the fuel running through them.
If your's overheated, then I suspect an obstruction, making it work harder and reducing fuel flow.
Blow through the lines with compressed air, and check the tank for contamination.

John

[Penelope Stopit]

This has brought back memories

You will very likely find that the contacts at the top end of the pump need cleaning and adjusting or replacing and setting up

The coil on the pump is overheating because there has been a constant current running through it due to the points remaining made rather than operating On/Off/On.....and so on

There's a flick-over mechanism that makes and breaks the contacts

The magnetic field being switched On/Off/On.....and so on is what moves the diaphragm to give the pumping action

Read this, it's a good article http://www.da7c.co.uk/technical_torque_articles/SU...

There are several videos at YouTube that show operation and the repairing of SU pumps

[crankedup]

Thank you both for quick and informative replies.