Morris Minor Owners Club

I've just overhauled Ted's fuel pump, standard AUA66, with a kit from Burlen. I set it up using the instruction and with help from this chap.

https://www.youtube.com/watch?v=oU5uLjuOQdM

The pump works but is a lot noisier than the spare I've got and runs slower too, more of a thunk, thunk, thunk, thunk whereas the spare is almost a buzz. I've adjusted the diaphragm one way then the other, set the points stops gaps but still the same. The pump does deliver plenty of fuel but it doesn't seem quite right, any advice welcome.

Cheers

Check it out with a Voltmeter. Is it earthing correctly?
Have you got full voltage across the points or are you dropping any across the earth side?
I'm just thinking that if you're dropping a couple of volts somewhere, it might make it a bit sluggish to operate.

I'll check that tomorrow, I'm sure the earth connections are OK as it's the same on the bench and on the car. I'm wondering if the new diaphragm is causing more mechanical resistance than the old one in the spare pump

That's an idea, if the diaphragm is thicker/stiffer I imagine it would have the same effect.

I connected the fuel line to the tank (I was running it on a petrol can in the engine bay) and put a gallon in. After a good old clatter as it primed the pump settled out to the occasional click. The engine fired up first kick and the pump seems a lot quieter for some reason now it's running from the tank, I'll call it fixed

I think that the fuel the pump is pulling would provide a damping effect on the pump mechanism by providing an amount of resistance to the diaphram movement. The longer pull from the tank versus the can in the engine bay would provide greater damping.
That is my theory Ahem .
Don

don58van wrote: ↑Tue Jun 14, 2022 11:13 pm I think that the fuel the pump is pulling would provide a damping effect on the pump mechanism by providing an amount of resistance to the diaphram movement. The longer pull from the tank versus the can in the engine bay would provide greater damping.
That is my theory Ahem .
Don

I agree, past posts, including this segment

panky wrote: ↑Mon Jun 13, 2022 8:57 pm ...as it's the same on the bench and on the car.......

didn't mention that the 'on the car' wasn't actually correctly installed but fed from nearby container, undoubtedly at a similar level, if not higher than the pump.
The Minor pump is intended to suck fuel from 10ft away and raise it over 2ft.....

But at least it's sorted now.

The petrol can was sitting on the nearside tie plate and lower than the pump but admittedly not as low as the installed tank. The dampening effect does sound feasible and that, coupled with the new diaphragm, could well explain the difference to the spare pump so I'll go with that. I guess the only way to be sure is to spend another £50 plus p+p and overhaul the other pump - nah I'll stay as I am

Different overall configuration of distance and height of liquid to be lifted.
If it sounds OK now, I'd stick with it.