Engine not running smoothly

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bmcecosse
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Post by bmcecosse »

Show us a picture of your carb ! Don't panic - no need for garage - yet!
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Geraldine
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Post by Geraldine »

Just went to take a pic of my carburettor to find that the battery is flat on the camera! Will do tomorrow, just really wanted to ask whether its OK to use the car , wanted to visit someone tomorrow but am a bit wary of driving it in case it dies on me! I suppose it will be OK once I get going, but want to be sure.
Thanks for your help. much appreciated.
bmcecosse
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Post by bmcecosse »

Well - if you can get a picture - we can help you rather better! Stick some new batteries in the cam - and get snapping!
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Geraldine
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Post by Geraldine »

Here is picture of carburettor:

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bmcecosse
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Post by bmcecosse »

The little screw on left of this picture is the normal 'idle' screw, the fast idle for use with choke is underneath slightly to the left - with a little spring around.
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ani
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Post by ani »

BMC - wouldn't it be a good idea to clean out the carb - doing this made a huge amount of difference to mine. Although some of the much had also got into the petrol pump which also have to be dismantled and cleaned - plus new contact points.

bmcecosse
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Post by bmcecosse »

Of course! Always a good idea - if Ger knows what to do - otherwise could lead to all sorts of mayhem!!
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ani
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Post by ani »

Very true - I did have a bunch of great helpers at the National. It's a completely different matter if you're on your own. Looks like Geraldine could do with a Minor friendly neighbour.

cormorant
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Post by cormorant »

Hi Geraldine you might find that your Minor only needs 3/4 choke to start it in this warm weather anyway from cold. The chugging you describe could be that the engine is getting too much fuel. It's difficult to say as "chugging " could be interpreted in different ways and without actually hearing it.....normally when the car starts you push the choke back in as far as you can without the engine stalling, and after a few hundred yards you can push it in all the way . I would start the car up and reduce the tickover to a sensible level then see how the car runs and what the plug colour is. Then you can adjust the jet underneath as necessary, a bit at a time. Every time you adjust the jet you may have to reset the tickover a bit as this will be affected. You are aiming to get the smoothest possible tickover.

If you think you have adjusted the jet too much and completely lost the setting you can always get the engine running as best you can, let it warm up, and screw the jet up until the engine starts to falter ( mixture now too weak). Now at least you know you will have to screw it down again, if you go too far it will start to run all lumpy (mixture too rich). I suspect that from what you say the mixture is too rich anyway ( you mention sooty exhaust, chugging=lumpy?) which is why I am suggesting screwing the jet up to start with.

Don't be afraid to try again, the correct setting means messing about with the jet and the idle speed, and continual little tweaks and listening to the engine, it's not something you do just in one go. If adjusting the jet means the tickover rises, well adjust the tickover back down again, see if the tickover is nice and smooth. If the engine speed can be made to rise with a further small turn of the jet, well do it and adjust the tickover again.
Geraldine
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Post by Geraldine »

Thanks everyone, think I have been getting a bit obsessed with this!
We did turn the right screw for idling speed, as Cormorant says I will have to do a bit of "tweaking" and see how it goes.
Charged the battery tonight which helped as well!
bmcecosse
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Post by bmcecosse »

I'm lost - how did charging the battery help with this ?
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Geraldine
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Post by Geraldine »

Yes it was rather unconnected with what I was talking about, am not making much sense at the moment!
End of topic I think!!
bmcecosse
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Post by bmcecosse »

Ok - just wondered if it had been struggling along on low coil volts with dynamo not charging.
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Geraldine
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Post by Geraldine »

I think dynamo OK, we had been starting the engine a lot while trying to sort out the idling speed and also the windscreen wipers. Had also made lots of short journeys recently.
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