3 replies to this topic

[ben.mini]

Hi All,

 

So my Mini hesitates under light throttle. I can be driving along, a nice cruise, but if I press the throttle lightly to speed up the engine hesitates. If almost feels like a misfire but not. Giving it more throttle to full throttle normally cures it until next time. This happens in all gears and is not dependant on RPM. 

 

The engine is a 1275 from an MG Metro. I have set the timing by idleing at 2000 rpm adjusting till revs stop rising then back off a bit, took for a drive and backed a little more off due to pinking (65D dizzy). The carb is a HIF44, have checked oil in the dash pot and topped up. 

 

I am trying to work if it is ignition or carburettor related. Could the oil be too light in the dashpot? Could the spring be too light and the hesitation being caused by the damper opening too quick? Or the jet set too lean at lower throttle openings? Or could it be the timing advance? Well I mean they are all the things in my head, but I am struggling to put an order to them.

 

Has anyone seen anything similar or could give any insights?

 

Cheers

Ben 

[blacktulip]

Try the a thicker dashpot oil and see what happens. Then report back. I have always used 3 in 1 oil with no problems and nearly every time I have experienced this issue it has been fuel related.

Edited by blacktulip, 01 June 2020 - 07:07 PM.

[cal844]

Use a thicker dash pot oil, I have to use 20w50 engine oil as my cars dont run as good with anything else

[ben.mini]

Been away from the mini for a bit, so quick update. 

 

I decided to strip the whole carb down and give it a service. Well nearly every seal and O-ring was rotten, the choke seals being the worse. The Jet was also stuck in the bush so wouldn’t adjust. After giving everything a good clean and fitting a new seal kit, resetting the jet two turn below the bridge. She runs a whole lot better. very little hesitation, so now to just fine adjust the mixture I think.