won't start - now intermittent loss of power

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amgrave
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Re: won't start - now intermittent loss of power

Post by amgrave »

I know you have changed the fuel pump but have you done a flow test to see how much petrol is pumped up in say two minutes. There might be a restriction in the tank pick up or a small crush in the copper pipe under the car so at slow speed there is enough fuel coming through but as the engine requires more it is getting starved as the flow is restricted. Just a thought.

simmitc
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Re: won't start - now intermittent loss of power

Post by simmitc »

You've probably been through this (I haven't read all the responses) but having just had a condenser fail after 30 (yes THIRTY) miles, and got very similar sumptoms, I'd try fitting a known good condenser - if such a thing can be found these days.
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Re: won't start - now intermittent loss of power

Post by bmcecosse »

Is it not now an electronic dizzy ??
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LouiseM
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Re: won't start - now intermittent loss of power

Post by LouiseM »

Yes, although the first thing I replaced on the old dizzy was the condenser. ESM are now selling a Distributor Doctor condenser which might be worth trying Simmitc: http://www.morrisminorspares.com/igniti ... ty-p831043
amgrave wrote:I know you have changed the fuel pump but have you done a flow test to see how much petrol is pumped up in say two minutes.
A flow test was done with the previous pump by another traveller owner who stopped to help when it broke down and he said it was OK. I could try another one - can you post an 'idiots guide' to doing this. It was pouring with rain when the last one was done so I wasn't paying too much attention. Thanks!


Eric - 1971 Traveller
leafie
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Re: won't start - now intermittent loss of power

Post by leafie »

Many years ago I remember we had a transit van at work that had the same symptoms, the problem turned out to be a partial blockage of the fuel line which was not enough to stop the engine but would starve it of fuel at anything above 50 mph. So might be worth looking into if all else has failed to find a resolution.
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Re: won't start - now intermittent loss of power

Post by LouiseM »

I think a blockage is probably the likely problem, as everything else has been tried! Probably won't be able to sort it before the National though. How easy is it to change the fuel line, if needed?


Eric - 1971 Traveller
leafie
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Re: won't start - now intermittent loss of power

Post by leafie »

Hi Louise,

A simple enough job just have to watch you don't damage the thread on the new fuel line and I would take the opportunity to take the tank out and clea it.

Before you do that is the flexible fuel line between the pump and the carb an old one? If so it is possible that is collapsing when fuel demand is high, changing that is a two minute job and if that doesn't work you'll always have a spare.
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Re: won't start - now intermittent loss of power

Post by bmcecosse »

To flow test - just simply take the pipe off the carb and stick it in a container -and switch on. It should pump a good pint of fuel through in 2 minutes. In an hour that would be ~ 4gallons - so if say you were running at 60 mph - that would equate to 15 mpg, which I think would be excessive in the extreme. Even if the pump only managed 1 pint - that would still be = 30 mpg at 60 mpg..... and your car should be doing better than that unless there is something sadly wrong.
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Nickol
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Re: won't start - now intermittent loss of power

Post by Nickol »

pints...gallons.....mph....mpg.....
Roy, you are in Scotland - you belong to the world ..what are These strange measurements ? :D :D
Gott schütze mich vorm Sturm und Wind und Autos, die aus England sind.
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oliver90owner
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Re: won't start - now intermittent loss of power

Post by oliver90owner »

is the flexible fuel line between the pump and the carb an old one? If so it is possible that is collapsing when fuel demand is high, 


I think you can discount this possibility. The fuel line after the pump should be under positive pressure. A build up of dross behind the float valve could be a further possibility.
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Re: won't start - now intermittent loss of power

Post by simmitc »

Do not discount the possibility of collapsing felxible pipe. It is entirely possible for a flap to start peeling with the loose end facing the pump. Fuel flow then presses the flap further until it seals sufficiently to cut the flow. This has been seen on both fuel and brake pipes.
amgrave
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Re: won't start - now intermittent loss of power

Post by amgrave »

When you do the flow test it would be best if you can pump the fuel into a clear container is poss. One thing to watch for is does the flow slowly decrease and this will require at least two minutes pump time. If you disconnect the flexible pipe from the carb it will check the pipe too. Report the results back and we will take it from there.

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Re: won't start - now intermittent loss of power

Post by taupe »

I havent read the whole thread but have you checked that the air filter is clean, this wont explain all of the symptoms but can lead to the car faltering at higher speeds due to restricted air flow....Try a run out with the filter removed?

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Re: won't start - now intermittent loss of power

Post by bmcecosse »

Nickol - now we have escaped from the meddling nightmare of the EU -we can and hopefully will revert to using IMPERIAL units - and selling our bananas in any size bunch we like -and weighing them in POUNDS and OUNCES !!! :D
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LouiseM
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Re: won't start - now intermittent loss of power

Post by LouiseM »

Thanks guys for the advice so far.

Leafie - Funnily enough I had the same thought this morning about the fuel line between the pump and the carb so ordered a new one first thing, which should arrive tomorrow morning. The current one looked fairly new when I got the car 2.5 years ago, and looks in good condition, but it is the 'cheaper' type so I've ordered one of the better quality ones. Will have a good check of the current fuel line tomorrow.

BMC - Thanks for the instructions, I'll carry out the flow test tomorrow.

Amgrave - I was planning on using a plastic 'jerry can' which I've already got but it isn't clear. Would a plastic water/milk bottle be any good, or a measuring jug, or would a glass container be better?

Taupe - I checked the air filter last time I had this problem but will check it again.

I'll post back with results tomorrow!


Eric - 1971 Traveller
amgrave
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Re: won't start - now intermittent loss of power

Post by amgrave »

If you can't see the fuel flowing into the container you have try and do it by holding the end of the pipe above the neck and observe the flow that way.

bmcecosse
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Re: won't start - now intermittent loss of power

Post by bmcecosse »

And if you can get the pipe under the surface you will be able to see if there are any 'tiny bubbles' coming through with the fuel. I think the Milk people may object to you using a milk bottle..... :o :roll:
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LouiseM
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Re: won't start - now intermittent loss of power

Post by LouiseM »

No glass milk bottles around this neck of the woods Roy, but have managed to get an old style lemonade bottle and I've marked up where the pint level is so all ready to give it a go in the morning.


Eric - 1971 Traveller
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Re: won't start - now intermittent loss of power

Post by LouiseM »

Did the fuel flow test - a pint in about a minute. Flow seemed regular and no sign of air bubbles. The fuel line between pump and carb had started fraying at the carb end but the rubber seemed OK. Fitted the new fuel line anyway then took him for a run. Was running well, and managed about a 2 mile stretch at 60mph around 25 miles into the journey, then all of a sudden it started to lose power and there was a rattling noise which I hadn't heard previously. Slowed down to a halt and then would turn over but not start so I had to call out a recovery truck.

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Not sure what the problem is - possible blown head gasket? There was a bit of mayo in the rocker cover neck, but no water in the oil. Radiator level was fine but there was an oil leak which seemed to be coming from the centre of the block, near the manifold (not from the rocker cover or sump). Anyway, he's now at my local garage and they are going to take the head off so Eric won't be going to the National tomorrow :(


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Re: won't start - now intermittent loss of power

Post by bmcecosse »

He never does..... Head gasket is possible - the flow test is barely enough - but it should be enough. Only takes 30 mins to lift the head - what did they find?
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