Hey gang...reluctant to post again but darn if I am stumped once again....months ago my car would not start because the fuel pump would not run....I ended up changing the battery, the distributor cap, cleaning the distributor out including trigger points, replaced the wiring harness with a tested replacement, replaced the ECU with one that seemed to function properly compared to my old one, replaced the Pertronix, and fixed about everything else I saw along the way. After replacing the wiring harness the car started and ran like a top....and has for over three weeks now. But today, in somewhat hot weather in Los Angeles, the fuel pump failed to run again after about an hour or so of running great. I swaped a bunch of relays and checked all of the fuses.....I am a bit perplexed at this point as it was so much fun to have my car back in action and today was was a total surprise and let down. Any ideas out there? I have not replaced the relay board and I do have an extra and I have not jumped the fuel pump like before to verify wires and pump function...I will report back on that once I do the jump test....welcome any comments and my mentors have been fantastic but running out of ideas.....all ears at this point....thank you very very much!!
gg

The tranny ground has been discussed so I guess I will replace that with a new one...all other grounds have been inspected and cleaned...WTF??
Thank you,
gg

Hi,
With your dizzy cap off, and someone turning the key, watch and make sure the points are opening and closing.
( that is if your car has points)

If the dizzy shaft has rust on it. It will sand the plastic rub strip on the points, and you car will act like it ran out of gas.

Also, I’ve heard remanufactured fuel pump don’t last long.

( on a side note, at Laguna Seca, probably a rennsport, I saw Hurley Haywood in an orange 914, driving like a madman, zipping in & out, passing several cars each lap, and then holding first place, then the mad driving ended, and he headed to the pits.
Later, I asked him what happened, he said his fuel pump lost pressure)

Thank you Scott...I have Pertronix electrical ignition...no points...thank you very much...
gg

Have you done the solenoid fix? Takes 20minutes.

To verify just jump the hot to the yellow on the solenoid, if it turns over, that's your issue.

I guess I should ask if the thing was turning over .. I assumed it was not.

If it is turning over, vapor lock could be an issue. My pump doesn't sound like it's running if I am pumping fumes.

Where is your fuel pump? Is it in the engine bay? That location was prone to vapor lock in hot conditions.

Just idea or suggestions:
1. Vapor lock- it will not run when hot and should run again when engine is cold.
2. Pertronix - do you have sparks on all spark plug wires? If not try to use contact point to test if you will get sparks. Pertronix usually get burnt when you leave your key On for awhile without running your engine. It just shot down even while you are driving it.

Greg,
Like the rest, I'm leaning toward vapor lock. My 3 port pump ran but was probably weak at best.
Car ran with no problems in cool weather, but as soon as it got warm (not hot outside just warm)
it would vapor lock and die leaving me stranded until it cooled down.
I would even carry a can of compressed duster for computers, as it comes out cold, with limited success.
I finally found a 75-76 blister and moved a new 2 port pump up front under the tank. Happy to say not a single problem since.
The car starts better, idles better and runs better overall. I should have moved it years ago.
Good luck with your problem.
Here are a few pics.
Mike
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I did have to change out my relay board as all the potting was cracked and missing quite a bit. A handful of connections looked suspect. It did cure a lot of electrical gremlins (fuel pump included). I think I might have a spare one if your in need.

Well...my battery was well charged and when I did the jumper trick on the fuel pump relay socket all I got was some sparks....fuel pump did not go on like before.... Hmmm? Any chance it is the relay board? Or is this a slam dunk on the fuel pump being toast? I hate going under the car to replace it....I sure wouldn't mind if I had a full height lift....I am 67 years young but I still am tired of lying down on the concrete to do the work. Any thoughts would be greatly appreciated and if anybody has a three port fuel pump I would love to hear about it. I like the idea of relocating the pump to the front trunk but I do not want the extra work right now....five months down and cooler weather is coming soon so I need some driving time....thank you and keep those cards and letters coming!
All the best,
gg

If you suspect the fuel pump, just get a fuel pressure gauge and see what it says. You can do that from topside. Where are you in LA?

Woodland Hills....I appreciate any help that you may offer....thank you very much!
gg

If you jumped it did the engine turn over? It's not clear from your posts what is actually happening.