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Hind Sight Is 20/20 - Fuel lines

PAUL161

Great Pumpkin
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I took the "B" out yesterday for the first time in about a month, got about a half mile from the house and she started to act a little funny. It sounded like fuel starvation as it would sputter, die a little and then pick up again. I made it back home and checked the fuel pressure and found out that I had more air in the line than gas.The pump is fine ,it's new. Problem was a deteriorated fuel suction line. The braided banjo one. When restoring the car, I put the old banjo line on,(TEMPORARILY, I thought), so I could check out the system with intentions of installing a new one. Well, naturally I forgot about it until yesterday. Moral of this story, Don t trust old fuel lines, especially the braided ones where you can't see the condition of the line inside the braid. Every line on the car was replaced with new, EXCEPT, that one. As I said, hind site IS 20/20.
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A new one is coming from Moss. PJ
 
On the topic, sort of. When I turn the key on, no ignition just the accessories position, my fuel pump clicks once about every 6-7 seconds. This is not the clicking we hear when first turning the key that "fills" the line. This is after that. I've tapped it with a wrench, but I think I might need a bigger wrench. Fuel pump dying?
Car runs fine otherwise, plenty of fuel delivered.
 
If you have a SU fuel pump, the ticking you are hearing is normal, other than it shouldn't occure when the accessories position of the ingnition switch. When the float bowls are full and the pump is energized it will tick over anywhere from 5 to 15 or 20 seconds.

The fact that your pump is being energized when in the accrssories position indicates that it is hooked up to the wrong place, it should only come on when the ignition is on. That said, the original ignition switch ia 66 MGB doesn't have an accessory position, where only the radio circuit and some other auxiliary devices are getting power. The original ignition switch in a 66 only has three positions - off, on, and start.
Cheers,
 
Thanks Dave, The key is indeed in the on position. Are you saying that it will tick at 5-15-20 second intervals (roughly) or that it will only tick for up to about 20 seconds or so? The reason I ask is that it will tick every 6-7 seconds until I shut off the key, could tick for five minutes if I left the key on for that long. I don't know if it does it when the engine is running, but I'll check that tonight.
 
Mike, It'll tick at some interval, be it 5, 15 or 20 seconds between when energised (key in the "on" position). It'll likely tick more frequently when running (I hope /bcforum/images/%%GRAEMLIN_URL%%/wink.gif ) but hearing it is a bit more problematic with the engine running. The pump is a diaphragm type and if the pressure on the inlet and outlet sides are relatively equal (as with the key on, engine not running) it will take a while for it to "cycle". If you're worried, get a "suitable container," pull the supply line off the carbs and direct it into the container and switch the iggy to position one. It should tick "woodpecker" rapidly and pump about a pint a minute (actually volume varies with whichever model pump you have).
 
Doc explained it a little better than I did. It is normal for the pump to tick over at a very slow rate after it has filled the float bowls. The rate at which it ticks over depends on how well the internal check valves are sealing. based on that, your pump is working normaly.
Cheers,
 
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