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Fuel pump leak

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tahoe healey

tahoe healey

Yoda
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I have a square body original fuel pump on my Phase 1 BJ8 that has decided to leak. The leak is between the square body and the tubular housing at the flang. The 6 or 8 screws seemed a little lose but tightening them didn't help. We are talking neg ground conversion. The pump works fine and strong.
The problem is a 300 miler we are scheduled for nest Saturday. Without opening it I'm guessing its the diaphram. What else will I need? Or should I just get a new one and rebuild the old one as a spare at my leasure? With a strong pumping, any thoughts on rebuilding after the first trip and before San Diego (a 2000 mile trip)the end of June?
 
My vote is to get a new one..rebuild the old one and keep the spare in the trunk..With my BJ8 I always had a spare distibutor and fuel pump...along with my phoropter and trial lens set!!
 
Just some inside humor!!!!
 
Will, I opted for a new SU square fuel pump. I will try to rebuild the original later. What they don't tell you is that the mounting bolts form the original do not thread to the new ones. Now I have to wait to properly mount it.
It seems to work fine but it "ticks" too fast compared to the old one. I assume it is set properly from the factory. I'll run her tomorrow to see how well it works. I'm trying to get it set for a long weekend run. Any thoughts about the rapid ticking?
 
Wow - You got an original expensive square model pump. I think these were original only to the early BJ8's.

I don't know that there is any correct "ticking rate". It ticks faster if it is moving a lot of fuel or if it is trying to move air in the fuel. As the pressure builds up in the carbs, all SU pumps should reduce the ticking rate.

If the carbs are full & the engine is stopped, the rate should be very slow like once every few seconds. Ideally it would be zero except there is always slight leakage of the pump's valves. The tick rate will increase as the fuel flow requirements increase with engine load & speed.

If the carbs are full with the engine stopped & nothing is leaking, including the float inlet valves, and the pump is still ticking frequently, the pump is likely sucking air from a leak on the suction side of the pump.

There have been rare cases of new pumps not having the pump stroke correctly adjusted but this is not likely.
D
 
Thanks, Dave. She ran well today and it seems to be settling in and doesn't tick very long anymore.
Moss said these pumps were on Jags and a few others. I've tried to keep everything as close to original. And yes, expensive.
The old one had a good diaphram. It appears the leak was from the gasket beside the diaphram. It should make a good spare.
 
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