petrol filter empty

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sidsmith
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petrol filter empty

Post by sidsmith »

Hi all you moggy men, I started mungo up in the garage today, got it warm and let it tick over on a faster than tickover speed. (by adjusting the carb) what i would like to know is, the petrol pump (elec') is working ok, the car as I said was ticking over but I couldn't see any petrol going through the filter, is it normal, does the petrol go through that fast that I can't see it or should the filter be full all the time. I ask because the last couple of times I have been out in Mungo he cut out a couple of times and then after 5mins started again. while it was ticking over in the garage everything seemed fine , I let it go for about 7 or 8 mins and it never cut out at all. your help would be most appreciated. cheers
ColinP
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Post by ColinP »

Sid,
You need to make sure that the pump is tiicking over as well.

The standard fual pump will tick (noticeably) while the engine is running.

I don't know wehre your fuel filter is - mine's part of teh fual pump so it isn't visible without unscrewing it.

What engine/pump/carb/etc do you have?

Colin
Stig
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Post by Stig »

I'm guessing you've put an in-line fuel filter before the pump. I've got the same and it only ever looks about 1/3 to 1/2 full - that's just the way they are. As for it running OK for several minutes, well, it'll run on idle for a few minutes on just the fuel in the carb's float chamber, ry disconnecting the supply to the fuel pump and you'd see. (careful of sparks if you do try this!)

Can you head the pump tick occasionally at idle and more regularly when running?
Rob_Jennings
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Post by Rob_Jennings »

Do you have the heat shield fitted over the copper fuel line to the pump?

The fuel line tends to heat up because its above the exhaust and the fuel boils. The air bubbles in the line cannot easily be pumped out by the fuel pump so the engine starves. But once cooled a little all is fine, thats your 5 minute 'fix'. Also at tickover the engine will warm, but not get as hot as when it working hard.

I have a fuel filter in the line and as said above it never looks very full, but works fine.
Rob
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Kevin
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Post by Kevin »

Do you have the heat shield fitted over the copper fuel line to the pump?
Dont see them fitted that often and it was a Grumpys Kit and it didnt seem to make much difference.
Cheers

Kevin
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sidsmith
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petrol filter empty

Post by sidsmith »

Hi all, I have a SU positive earth fuel pump, with a pipe coming from the fuel pump to a see through filter and then it goes to the carb. I cant hear any ticking over when the car is running, only on start up when it fills the carb'. I hope this can help identify the problem. cheers sid
Kevin
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Post by Kevin »

Well you should be able to hear the ticking when its running although it will only be occasionally as the fuel is used, your engine isnt so noisy you just cant hear it is it.
The other check is to take the pipe of the carb and put it in a jar and check the fuel is being pumped be careful as it can be quite a strong squirt.
Cheers

Kevin
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sidsmith
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petrol filter empty

Post by sidsmith »

yes i did take the pipe off and put it into a big jug, i then turned the ignition on and the petrol came through but as soon as i covered the end of the pipe the petrol stopped which i should imagine is normal. The only other thbing i haven't tried is cleaning the contacts on the pump as you have said the pump should click periodically my doesn't it only clicks on the initial start up.
cheers sid
bmcecosse
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Post by bmcecosse »

The car will not run unless petrol flows. The heating up fuel thing never happens - look at Minis with pump and fuel lines right beside exhaust system trapped down behind the engine - they never have this problem. There si probbaly just an air bubble in the filter - and fuel is flowing through below. Check oil in carb damper for cutting out thing - also check if vacuum forming in petrol tank. Next time it cuts out - give the fuel pump a dunt - if it then pumps away furiously - then there is the problem!
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57traveller
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Post by 57traveller »

s
57traveller
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Post by 57traveller »

[quote="bmcecosse"] give the fuel pump a dunt [/quote]

Scottish for hit it! :wink:

p.s I've asked before but never had an answer, why don't the quotes work properly for me??
57traveller
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Post by 57traveller »

[quote="57traveller"]

p.s I've asked before but never had an answer, why don't the quotes work properly for me??[/quote]

Many thanks to all who responded to this question - very much appreciated!! :(
Kevin
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Post by Kevin »

The heating up fuel thing never happens
In the frozen North perhaps where your points of view obviously rule. Try explaining that to cars broken down in traffic queues waiting for things to cool down furthur down south (you obviously didnt go to Donnington) and perhaps you can explain why Grumpy`s went to the effort of making a kit to try and help the problem it cant have been for those that also own an MG and thought that as the MG`s have them their Moggie should also have one so as not to feel left out.
Cheers

Kevin
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bmcecosse
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Post by bmcecosse »

Well - as you know there is a great long thread on the matter already - but the point is - it NEVER happens with Minis - so , why does it (seemingly) happen sometimes with Minors - although it has never happened to me. The Mini fuel pipes are much closer to the exhaust and in a much smaller and very hot space! Both have 'puller' pumps, but the Mini one is block mounted mechanical - so I can only suggest to anyone who is plagued by this - try a mechanical pump if the block has a hole for it. Alternatively - lower the existing pump so it draws on the level and then pumps up to the carb (yes, already suggested by others) or - fit a pusher pump (as fitted all early Minis) at the rear.
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Cam
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Post by Cam »

The answer is simple. The mini low pressure side is not near the heat source. The high pressure side is which RAISES the boiling point. With the Minor, the LOW pressure side is near the heat source which has the effect (due to the fuel being at low pressure) of DECREASING the boiling point.

It's VERY real. Many, many Minor owners have experienced this and I think it's madness to say that something 'never happens' just because it's never happened to you! :roll:
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