QuestionQUESTION: After a year rebuilding the engine, one of the two fuel pumps on my '58 XK150S doesn't pump. I've taken it apart and cleaned the points. How can I check if the solenoid coil is ok or do you have any suggestions before I buy a new pump? Thanks.
ANSWER: Hi Bill,
The simplest way is to Just connect a 12v battery to the solenoid wire for a moment with the points disconnected, to see if it becomes an electromagnet and pulls the diaphragm in. If the pump is old, the diaphragm may be hardened and the solenoid can't pull it to operate it so that needs to be looked at also.
Or you could use an ohm meter on the good solenoid and check the ohms and compare it to the one that does not work.
Howard
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QUESTION: Hi Howard,
Thanks for the good info. I'll do the checks you recommended. I can push the diaphram up easily with my thumb and the diaphram looks quite new. I changed them some years ago. If the solenoid is bad, can it be fixed (and by whom) and also, can I just run the car on one pump? Some people have suggested buying a non-original pump to replace both. Don't like that idea, but the replacement SUs are $350 +.
AnswerSorry Bill, I don't know of anyone that fixes bad solenoid coils. To tell you the truth I never tried to get the coil out of one. If you can get it out of the iron case you could rewind the coil with coil wire from a electric motor repair shop (if you can find one) or measure the size of the wire and order a spool of coil wire from someone like Radio Shack or some electronic shop. You may even find a break in the wire that can be repaired. If it is bad, you have nothing to loose trying and $300+ to gain.
Any pump that can maintain from 1.5 to 3 PSI pressure on the carbs would work.
Howard
