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Car stutters and stops - fuel pump problem?

Andy McGhee said:
What's the number on the side of your carb?
I ask because it can affect the float setting - on some 28IFs (like the one below), the setting is 8.9mm rather than 8.4mm. What setting did your manual give?
If you do go for a new (perhaps remanufactured...) or secondhand carb, it's important that the specification is right.


View attachment 29288
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V05 079

The nearest carb ref in our manual is V05 078, which gives a measurement of 8.9mm and that’s what it is set to and it’s what it was set to.
 
When cars stops have you tried take of fuel hose at carburetor and crank engine to check you got fueling to the carburetor
 
I've had another thought: Your remark about the car "spluttering and stalling after a few minutes" suggests something either warms up or changes after this length of time, causing the engine to fail. The fuel supply has been confirmed as being O.K., so the electrical side might be faulty. Have you considered the coil might be failing, and that after a few minutes it warms up, and in due course the insulating material inside becomes less viscous and therefore the coil fails?

I appreciate we're all scratching around, here, so any idea might be worth a try!
 
if I read you correct Edwin- avoid changing coils at all costs-as if done ,this might lead to driveshaft failure...... -R.
 
I suppose you could say that driving the car caused the driveshaft to fail. So the coil failure was protecting me from that, so by replacing it I was asking for trouble. My fault entirely. Let that be a lesson to us all.
 
Hi Everyone

Thanks for all your helpful suggestions and advice.

The car is now running again properly...so what happened?...

Took off the distributor, it was very dirty and then noticed that the points were quite black, which couldn't be seen with the distributor on the car, this led me to suspect the condensor needed replacing. Cleaned up the dizzy, replaced with a new condensor, cleaned and gapped the points, put dizzy back on car.

Car now runs as it should. Interesting that I was convinced it was a fuel issue and my wife always tried to get me to look at the electrical side of things!

Took it for a Portuguese IPO (MOT) and the emissions were too high/rich. The mixture screw was 3.5 turns out, so have turned it down to 2.5 and car runs OK even though the mixture is now leaner. Any recommendations for mixture screw settings ready for re-test as it is strict here? Will it run on a leaner mixture?
 
I'm glad it's sorted! The condenser breaking down when it warmed up is a common problem, and is often overlooked when searching for the answer. I thought the coil had suffered a similar problem! As regards the mixture, you want the engine to run on the mixture as recommended by the manufacturer. Too rich a mixture:
1/ Wastes fuel.
2/ Is environmentally damaging.
3/ Fouls the sparking plugs.
4/ Causes uneven running and sluggish performance.
5/ Costs money!

As a rough guide, g-e-n-t-l-y screw in the mixture screw fully in, until it reaches its stop, then turn it out 2 to 2 1/2 turns and start the engine. Let then engine warm up and adjust the tick-over speed, using the idle speed screw. Once this is set correctly, begin s-l-o-w-l-y turning the mixture screw IN, until the engine begins to run unevenly. Then turn it OUT a half turn, check the tock-over speed again and go for a drive. If the car hesitates, the mixture might need to be a little richer, so screw the mixture screw out a quarter turn and drive it again. It really is a case of trial and error.

For an accurate guide, ask your friendly garage to use their exhaust analyser to set it properly! I'm not quite sure of the correct settings for a Renault 4, but 3.5-4.5% CO should give a decent response.
 
Joolzy said:
Hi Everyone

Thanks for all your helpful suggestions and advice.

The car is now running again properly...so what happened?...

Took off the distributor, it was very dirty and then noticed that the points were quite black, which couldn't be seen with the distributor on the car, this led me to suspect the condensor needed replacing. Cleaned up the dizzy, replaced with a new condensor, cleaned and gapped the points, put dizzy back on car.

Car now runs as it should. Interesting that I was convinced it was a fuel issue and my wife always tried to get me to look at the electrical side of things!

Took it for a Portuguese IPO (MOT) and the emissions were too high/rich. The mixture screw was 3.5 turns out, so have turned it down to 2.5 and car runs OK even though the mixture is now leaner. Any recommendations for mixture screw settings ready for re-test as it is strict here? Will it run on a leaner mixture?
Click to expand...
Glad you managed to get the 'old friend' working again. Up here in Tomar - i've been meaning to fix a - 'hesitating when under load syndrome' with my 1981 GTL. And checked the carb, fitted a new inline fuel filter & No result! Then moved on to the 'sparks' and cleaned & fitted new points... and then..... replaced the thing that undid me many years ago - yes the condenser! And for the princely sum of 6Euros i made the old girl run as 'sweet as a nut" = RESULT!
As for the emissions issue - mine failed on that last year, but it aint too difficult to screw in the mixture screw & ajust until it does the business!
Boa tarde amigo!!
 
I had a (fairly new) condenser fail. Although the engine didn't stop, it become incredibly sluggish (especially up hills).
 
The condenser (or capacitor-it means the same thing) acts as a smoothing device. When the condenser is working properly the amount of charge passed through the points is very little and so they don't burn out. If the condenser is not functioning properly the points have to handle a HUGE electrical load, and therefore they burn out, and they no longer act as an efficient switch, so the spark produced is less, and the car splutters-hence the struggles up hill or under load.

A condenser is easy to test, and I would change it when the points are changed, keeping the old one as a "just in case".
 
I had changed the condenser fairly recently, so it was still quite new when it failed. It didn't occur to me (or the mechanic!) to test the condenser first. Mechanic thought it was a carb issue to start with.
 
One of the problems associated with running older cars that have points & condensers is that no-one manufactures these parts in any quantity (or quality!) any more. Those that are "new, old stock" have, in many cases, degraded internally, owing to the ravages of time.
 
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