Fuel pump

[JJC]

This post also appears on the 4 forum. I’d be interested to know how many of us have been running pumps with the original AC diaphragm with no problems due to unleaded. Thanks. JJC

[mikej]

Well, it's statistically weak but I use a standard fuel pump that has not had a new diaphragm in at least 30 years (if ever). It does not leak and works just fine. I'd guess that Ethanol is more likely to affect the parts than un-leaded but as yet, I have not heard of any issues.....although if the diaphragm does swell slightly it may not have any effect? 

 

[Ian Vincent]

1 hour ago, mikej said:

Well, it's statistically weak but I use a standard fuel pump that has not had a new diaphragm in at least 30 years (if ever). It does not leak and works just fine. I'd guess that Ethanol is more likely to affect the parts than un-leaded but as yet, I have not heard of any issues.....although if the diaphragm does swell slightly it may not have any effect? 

 

Of course Murphy's Law means that it will fail soon.

Rgds Ian

[Hamish]

I had a fuel pump diaphragm fail on a hillclimb competition the smallest hole lost the suction pumping action and the car just died from full throttle.
But the fuel didn’t leak into the block from the tank.

a Dave Davies refurb fixed this 

but have since gone electric for other fuelling reasons.

[JJC]

Thanks for the replies. I’ll trust to the original AC diaphragm which replaced the failed after market one but will look at a petrol tap because a failed diaphragm drains the petrol tank into the sump under gravity. JJC

[ianc]

One of Triumph's stupid improvements was to remove the petrol tap when the TR4 was introduced.

Ian Cornish