Rebuilt fuel pump

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RobThomas
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Rebuilt fuel pump

Post by RobThomas »

The little sod sat on the shelf for years after it was rebuilt with a Burlen kit. Ticked away well enough. Not a single tick today, though.

I pulled it apart, span the diaphragm back a full turn from the point where it ceases to flick over, wedged the thingy up and then tightened everything down before the wedge came out. Is SEEMS to be trying very hard to flick over with about 75% of the solenoid movement but never quite makes it. Do the diaphragms dry out in storage? Some rubber grease or rubber softener? Bigger hammer? Do the coils become partially knackered?

Can tthe body of an MG Midget pump be substituted? I have one here and wondered if the differences are all in the upper body and spacer casting. Phil, You'll probably know this. :D
Cardiff, UK
philthehill
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Re: Rebuilt fuel pump

Post by philthehill »

Rob
If the MG fuel pump body containing the coils is the same length as the Minor then you will be home and dry.
Phil

RobThomas
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Re: Rebuilt fuel pump

Post by RobThomas »

Problem solved. New (a few years ago) diaphragm was as hard as nails when compared to an old one. Old diaphragm in...pump clattering away.
Cardiff, UK
philthehill
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Re: Rebuilt fuel pump

Post by philthehill »

Rob
Well done.
Had a similar problem with the neoprene diaphragm in a PCV valve which went solid.
Phil

simmitc
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Re: Rebuilt fuel pump

Post by simmitc »

I had exactly this when I fitted a brand new pump on the way to the National. I applied WD40 to the diaphragm, put the pump back together and all has been perfect since; so yes, they do stiffen in storage.
StillGotMy1stCar
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Re: Rebuilt fuel pump

Post by StillGotMy1stCar »

Glad you got it sorted.
The original diaphragm had an outside layer of clear plastic about the thickness of a supermarket bag bonded to the rubber. I wonder if the new replacements have this feature.
May be a case of older is better.
A hope the mice haven’t chewed the NOS ex MOD one I bought many years ago.

As a side note. Lots of people blame ethanol in modern fuels for this sort of issue, the only issue I’ve had with ethanol is with 2 stroke engines. When I add the oil to the fuel it makes the water absorbed into the ethanol separate out causing serious carb problems. So I now run my 2 strokes on expensive Aspen fuel, it is an Alkylate petrol, it burns very clean and plastics and rubbers don’t react to it and has a 5 year shelf life. However I still need to change my primer bulb every couple of years so ethanol wasn’t causing that to perish, the carb stays clean so worth the extra expense, my last gallon was £18 and will last me 3 years.
Regards John
RobThomas
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Re: Rebuilt fuel pump

Post by RobThomas »

There was a bit of crud in the fuel line on this one, too. I stuck a hose from a foot pump onto the fuel line nipple and gave it nearly 30psi before it surrendered. Now I've got fuel flow and the little sod runs! The dissy is stuck solid in the block and it is too hot to get my hands on it. I think it has been painted in and then left. I hope I don't have to destroy it to get it out. Next I need to source a complete set of headlights with buckets and rubbers. Where is the cheapest source?
Hmmmm.
Cardiff, UK
RobThomas
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Re: Rebuilt fuel pump

Post by RobThomas »

Simmitic. Did the WD40 resolve the issue in the longeer term? I was wondering about stewing the diaphragm overnight in WD.
Cardiff, UK
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