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#1
  This topic is about my 1976 MG Midget MkIV
Northern Midget Avatar
Northern Midget Norm Paterson
Haileybury, Ontario, Canada   CAN
1961 Morgan 4/4 "Joan"
1968 Fiat 600 "Luigi"
1976 MG Midget MkIV "None Yet"
I have installed SU HS-2 carbs on my 1500 engine. I am having problems with fuel. The fuel flows from the fuel pump to the rear carb, and then to the front carb. As soon as the engine starts fuel shoots out of the overflow hole on the rear carb. I have adjusted the float in the rear carb until the cows come home, but it doesn't stop the fuel from shooting out of the over flow hole...


Any suggestions would be welcome.

Norm

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Northern Midget Avatar
Northern Midget Norm Paterson
Haileybury, Ontario, Canada   CAN
1961 Morgan 4/4 "Joan"
1968 Fiat 600 "Luigi"
1976 MG Midget MkIV "None Yet"
I just checked my fuel pump pressure. I am using the mechanical fuel pump and it's at about 15 pounds per square inch. That seems high to me. Anyone know what it should be?

Norm

TheLastDeadMouse Avatar
TheLastDeadMouse Tim Vollmer
Potsdam, NY, USA   USA
Way too high, you want 2-4 ish. You should be able to pick up one for 30ish bucks at your local auto store that'll get the job done.

Edit: Sorry, I missed that you're using a mechanical pump instead of electric. I'm not familiar with how that set up works, but that's still too high if that's the pressure at the carbs.



Edited 1 time(s). Last edit at 2017-06-16 02:19 PM by TheLastDeadMouse.

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dickmoritz Avatar
dickmoritz Gold Member Dick Moritz
Philly 'burbs, PA, USA   USA
Post a photo of your carb setup. It's possible you have the fuel inlet going into the overflow port on the rear carb by mistake...

Dick



Errabundi Saepe, Semper Certi
(Often wrong, but always certain)

dlrhine Avatar
dlrhine Silver Member Dave Rhine
Columbia, SC, USA   USA
Hi Norm

Converted my 1500 to HS2s a couple years ago.
15 PSI fuel pressure is way to high, that will overpower the float needles for sure.
My mechanical pump puts out around 10 PSI & caused similar issues.
I installed an in line adjustable fuel pressure regulator from local parts store & solved that problem.
It may take rebuilding the carbs & a little bit of fiddling before you sort them to your liking, but once you get them right, they're nice little carbs!

Also, like Dick said, post pics of your setup...

Good Luck thumbs up



If it ain't broke, I'll fix it 'til it is! winking smiley

ice Avatar
ice Gold Member Larry Ice
Lawrenceville, GA, USA   USA
Like the other guys have said pressure way too high. With that much pressure you might be able to rent your car to do fracking for oil companies!
Never heard of a mech fuel pump producing that much pressure. Why not do a way with the mech pump, get a low pressure (low cost) electrical pump? Put on a blanking plate where the old mech pump mounted and Bob is your brother!



Iceman

Atlanta GA

60 AH MK1
62 AH MKII
67 Midget
71 Midget

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