11 replies to this topic

[ashparry_]

Hi all.. Got a problem with my 1983 Mini Mayfair. Almost every time my revs drop to idling speed it cuts out, even when engine has been run for a while. I'll come up to a junction, and when I go to idle it cuts out almost instantly. My mate says I could adjust the idling speed via the idle adjustment screw located on the dashpot?

 

If anyone has had this problem or knows how to fix it I'm all ears! 

 

Ash

[Cooperman]

It might be a sticky carb piston. If the piston drops too slowly, when you stop the revs drop but the piston is not fully down and the engine is artificially rich momentarily which can cause it to stall. Check the piston drop rate, assuming there is sufficient oil in the dashpot chamber, and make sure it drops with a slight 'click' as it bottoms out.

Alternatively, check for spindle wear on the carb butterfly spindle.

[ashparry_]

I'll get looking - thank you!

[KernowCooper]

It could also be running weak, thats a sign of cutting out when coming back to idle

[Cooperman]

Indeed it could be.

Just check the carb thoroughly, setting mixture and checking the piston drop. Then re-set the static timing, check the vacuum advance-retard pipe, clean and re-set the ignition points (if you have points ignition, and make sure the dizzy is advancing and retarding as it should. Set the tick-over when the engine is warm to around 800 rpm. Clean and re-gap the plugs to 0.025".

[Icey]

I've just been fighting with something very similar and it turned out to be a vacuum issue with the breather system. So I'd start with a general look over to see that everything is still connected and that none of the pipes have cracked/split. 

[andyapanel]

I've just been fighting with something very similar and it turned out to be a vacuum issue with the breather system. So I'd start with a general look over to see that everything is still connected and that none of the pipes have cracked/split. 

I had this and thought vacuum leak, too. It turned out to be the coil.

[ashparry_]

I've just been fighting with something very similar and it turned out to be a vacuum issue with the breather system. So I'd start with a general look over to see that everything is still connected and that none of the pipes have cracked/split. 

I had this and thought vacuum leak, too. It turned out to be the coil.

The ignition coil? I've just literally touched one of the wires very gently and it disconnected from the connection. It idles fine when started but it's when i press the accelerator and the revs drop after doing so is when it cuts out

[ashparry_]

Took a video https://youtu.be/2cwSJnumDgE

[andyapanel]

Have you had any success yet?

[ashparry_]

Have you had any success yet?

I topped up the dashpot oil a tiny bit and adjusted the idle speed very slightly but it still cut out that morning. When I drove it in the afternoon it stopped cutting out. Since saturday it has been running fine. Maybe moisture in the engine bay could have been the cause somewhere. I also had to rewire the ignition coil due to the wire breaking off the connection. I've had problems with coolant leaking from the overflow pipe so I've ordered a new cap for the radiator and I'll flush it and change the thermostat. Non-related really but it all helps! Stumped on why it cut out though.

[andyapanel]

It might be an idea to do a "wiggle" test on the Low Tension connections. Not a good idea with the HT leads, tho without insulating your hands.

its good you are mobile, tho.