3 replies to this topic

[Nero_1973]

[b]Model Austin Mini 1000
[b]Year 1973
[b]Description of problem
Yesterday It was going alright in the morning (8:20 am) and then again when i drove to tescos from college and back but then just an hour later when i tried to drive home it was coughing and jolting along, I sprayed some wd40 on the spark plugs and timing screw (like i was told to do and usually works) and turned it down a bit because it was running very very fast (i needed it going fast for my driving test a week ago because it kept cutting out when i was doing reversing manouveres). It was going ok after that until i got to the stretch of road which is 60 mph and before i had even accelerated it started to lose power doing the weird jolting thing again wouldnt go above 30 mph. Then the speed changes down to 40, then 30 and back up to 60 down hill, there it went up to 55 and stayed at 40 going up hill until suddenly it started jolting again.

It has been to the garage so much, had new spark plugs and point which they said should cure the problem and did for 2 weeks and now its back again!
Im going to fill it right up with petrol to see if that helps. i checked the oil and it was ok. the petrol gage says it is half full .

If anyone has any ideas i would be really grateful. ive asked this question before but i need some more advice. I just really cant think why this keeps happening, its getting quite frustrating!

thanks

[clambert81]

sounds like a fuel problem. Check the float bowl and fuel valve to see if any crud is blocking the fuel flow. Also check the float to fuel valve gap and the float itself to make sure it is not punctured.

[Brian422]

[b]Model Austin Mini 1000
[b]Year 1973
[b]Description of problem
Yesterday It was going alright in the morning (8:20 am) and then again when i drove to tescos from college and back but then just an hour later when i tried to drive home it was coughing and jolting along, I sprayed some wd40 on the spark plugs and timing screw (like i was told to do and usually works) and turned it down a bit because it was running very very fast (i needed it going fast for my driving test a week ago because it kept cutting out when i was doing reversing manouveres). It was going ok after that until i got to the stretch of road which is 60 mph and before i had even accelerated it started to lose power doing the weird jolting thing again wouldnt go above 30 mph. Then the speed changes down to 40, then 30 and back up to 60 down hill, there it went up to 55 and stayed at 40 going up hill until suddenly it started jolting again.

It has been to the garage so much, had new spark plugs and point which they said should cure the problem and did for 2 weeks and now its back again!
Im going to fill it right up with petrol to see if that helps. i checked the oil and it was ok. the petrol gage says it is half full .

If anyone has any ideas i would be really grateful. ive asked this question before but i need some more advice. I just really cant think why this keeps happening, its getting quite frustrating!

thanks

Suggest checking oil in carb dashpot.
Also suggest, if oil is correct, removing carb suction chamber, cleaning the piston and inside suction chamber.

[dklawson]

I second Chris' comment about this being a fuel issue. Running up to a low maximum speed and then experiencing bucking and jerking (or surging) is usually fuel related.

First trace the fuel line from the back of the car to the front. Look for any fuel filters along the line. Previous owners could have put them anywhere. Unless you know the history of the car, replace all the fuel filters on the assumption that they are old and plugged. If that does not address the problem, look inside the float bowl as Chris suggested. Remove any debris in the bowl, make sure the float valve can open and close properly, and finally... carefully remove the carb vacuum chamber and lift its piston up carefully to pull the needle out. Clean any debris/deposits off the needle and from inside the jet tube as Brian said.

That said, I usually focus on fuel problems last. It is ALWAYS a good idea to adjust the valves on a cold engine, then check and set the points gap and ignition timing. Never adjust the fuel mixture settings without doing a valve adjustment and ignition tune up first.