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Replacement Fuel Pump - useless priming lever


Stuart R
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After noticing a strong whiff of petrol at Triumph Fest 2014, I discovered that the top of the fuel pump was loose on my '69 Herald 1200.  Turns out that the top had been bodged on with a self-tapper which had run out of 'bite'.  Fuel was oozing out and running onto the starter motor.

 

So, got myself a new pump from one of my regular sources.  It looks slightly different to what was fitted, but all suppliers seem to be offering the same.

 

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Now, my Herald often sits around for weeks at a time doing nothing, so I always found between 5 or 10 pumps of the old pump's priming lever would be enough see the fuel drawn through the see-through in-line filter and hear it arrive in the float chamber.  That makes for an easy start with minimal cranking.

 

With this new pump, over a 100 pumps of the priming lever and the fuel just about gets to the filter with still another 2' of hose to go to reach the carb.  I've tried this with the tank filler cap open and closed.  I've given up on the priming and so now need a lot of cranking to get things started.

 

I have removed the pump from the block in an effort to make sure I hadn't got it installed the 'wrong' side of the cam, but it seems to go in easily enough so must be landing in the right place.

 

I'm going to take a closer look at the pump this weekend, as there is still a petrol smell and the top of the pump still seems damp at times.

 

Anyone else experienced similar with these replacement fuel pumps?

 

Thanks in anticipation,

 

Stuart.

 

 

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Hi Stuart

 

Certainly have. I too fitted one of the repro items from a well-known supplier, and they are made of some monkey metal that is like putty. The most careful and gentle tightening stripped the thread, and the fibre sealing washer had been fitted on the inside! I went back to five quid's worth of second-hand pump from a triumph breaker and have had no problems since with leakage.

On the matter of getting fuel up to the carbs, I have the same problem, and I think is down to the volatility of modern fuels. Even a short lay-up and the lines dry out, and you are on your way to flat battery city.

 

My own solution after a lay-up has been to mount an electric pump on a board shaped to sit on the front wishbone, with two long power leads with croc clips for the battery, and two good lengths of fuel pipe, one with a piece of copper line and a hose clip on it. I disconnect the fuel hose at the carb end, and use the pump to suck fuel through to prime the system, discharging into a fuel can as it comes through. I then reconnect the line, remove the pump kit, and she fires up within a few cranks. It only takes a couple of minutes, and saves the battery, and you could use any electric pump from a scrapyard.

 

Regards

 

Steve

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Stuart one thouht here is the primer lever wont do anything if the cam lobe is already holding the pumpmstroke down

the lever then just has no action to pull the diaphragm as its already gone.

 

 

turn the engine one revolution , to get the low part ofmthe pump lobe and see if it makes any difference

 

a electric is a good option, check the fuel hose to the tank reserve suction tube outlet is tight and not hard and sucking air .

 

if you jump to full time electric make sure its a max 2.5psi rating or you overload the carb float needle valve

and have to faf about with regulators

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Hello Steve & Pete,

 

Thanks for your thoughts and suggestions.  I can remember using in-line pumps with gerry cans and geneators - a rubber bulb was squeezed to get the fuel moving.  I might look out for one of them as they could be left in-line - so long as they can cope with modern petrol. 

 

I took the pump apart last night.  No fibre washer at all on the top of the casing and the nut has to be nipped up tightly to get a seal on the rubber O ring below that doesn't weep.  I opted for a nut spinner rather than risk a spanner after reading Steve's warning.

 

Took the rest of the pump apart last night and yes Pete, you're right -once the pump is on the downstroke the primimng lever has no efferct. It is just possible to feel the subtle difference in handle operation as you rotate the engine.  I don't remember the old pump having that limitation, but maybe it's just because ths new one is so gutless.  I saw about 5mm maximum stroke of the pump diaphragm.

 

I should add that the engine runs OK (noises aside) with no fuel starvation problems.  It's just a shame that with the old pump you could hear the fuel rushing to the carb as you pulled the lever, this one requires a lot more effort - even when you get the engine in a 'lucky' position.

 

 

Regards,

 

Stuart.

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i would not bother with an electric pump ,the modern ones for our type of car are not much good.

i used to run a mg and had loads of electric  pump problems as did many people--the club forum was always full of owners asking for pump advice,

hope you can sort your problem ok.

cheers

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ah ha  fit a air pump to the dash and pressure the tank, 

    just dont forget tp pump indicat steer and dive around a roundabout whilst pumpng like mad as the engine dies ....

 

             helped out  with an ERA   racer that had this nightmare   who   said concentrate 

 

Pete

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