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MG MGA - Fuel Starvation??

I noticed recently when driving hard up hill I sometimes feel a very slight hesitation. I immediately thought plugs , electrics and checked..found nothing untoward.
On a drive up very steep hills today the car just gave up the ghost .. not just a hesitation..and it happened about 3 times..once on a very steep climbing switchback. It was very unnerving ..as no continuous hard shoulder and big kenworths hoofing up and down .
I noticed the engine would restart right away and my little non standard rattler fuel pump was very loud and I had about 3 or 4 mins when I moved to when it ran out of umph.....dirty fuel filter says I.
I got to a little town called Braidwood and took it into the 1st garage....great people. They put in on the hoist right away and I had a cheap clear plastic inline filter on the suction side of the pump. The mechanic took the filter out and it looked clean but the inlet nozzle had a small crack in it......but no fuel leaked or could be smelt prior to its removal. He checked the pump and its little filter..all ok and put a new filter on the inlet .
The rattler pump is now much quieter and no 'hesitations' . I drove it hard up and down hill after the replacement so problem is solved .
I can only presume the small through thickness crack was letting air into the line ( ie line is under under vacuum ) when the pump was under throttle demand....even with a near full tank.
Any thoughts..
Neil Ferguson

Neil

With the SU pump you should not put a filter between it and the tank. What's the score with your non-standard pump?

Steve
Steve Gyles

The pump is facet type ..very rugged little sods but noisy at times ( at least you know they are working!) You can put a coarse filter ( ie strainer ) on the suction side but as always you need a large area and coarseness to ensure free flow and limit deltaP .I do have the suspicion that the one I put about 10 years ago ( and failedjust now) maybe was too fine or too small an area and created a vacuum on its inlet .
I have no idea about Su original config.. And filters ...
K
I do have a NZ FreeFlow pump I bought many moons ago and may change out the facet unit and reconfigure the suction piping for Easier maintenance.
Neil Ferguson

Neil
if the engine begins with a slight misfire as if it has gone down to 3 cylinders, which then drops to 2 cylinders, then only 1 and then stops altogether.
Then you are running out of fuel and probably have a fuel blockage ( fuel filter hidden somewhere in the fuel line for example)
It has happened to me a few times!
Colyn
c firth

Colyn..first time for me ....and I am now a specialist ( These days that title is given to someone who who has done something once before) . The hesitation is exactly as you describe with the addition that it only occurred climbing hills ..on the flat full steam ahead. I think air was getting in the line ....and the pump noise is consistent . I am away from the comfort of my garage and up in the mountains . ..and car is humming along..
Neil Ferguson

This thread was discussed between 10/02/2016 and 11/02/2016

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