5 replies to this topic

[bajean]

So today i decided to go for a quick drive in the mini, and noticed that when releasing the throttle pedal at a certain rpm ( low rpm 2000-3000 ) in gear the engine sometimes judders. It has never done anything like it before. When you press the gas again it accelerates normally ( engine feels strong no problems their ). Any idea what it might be ?

[MiniMadRacer]

Do you mean the engine judders as in revs being juddery or is it a mechanical knocking... if the latter.. check the engine mounts and stabiliser bars first

[bajean]

The revs seem juddery. The stabilisers both have poly bushings in them and the engine mounts are brand new as i just put the engine in february. It honestly seems like the throttle cable is getting stuck and releasing slowly causing the engine to change revs.

[MiniMadRacer]

A stuck cable would make it rev, but I wouldnt call that juddery... that would be just rev ing more than you expect.. is it the the standard SU carb, and if so check the oil in the dashpot, and maybe take the dash pot off and carefully make sure the piston is a smooth sliding fit in it... I say carefully as you dont want to drop either component or bend the needle

 

Could the juddering be the clutch ?

 

When it judders try pressing the clutch, and separately try pulling the choke to see if either make a differnce to the judder

[bajean]

The carbs are twin hs2s which i rebuilt. Ill give the dashpot oil a quick look if so ill top it up with some Su carb oil. I doubt its the clutch as its also brand new, with a new diaphragm, friction plate and so on. 

[cal844]

The carbs are twin hs2s which i rebuilt. Ill give the dashpot oil a quick look if so ill top it up with some Su carb oil. I doubt its the clutch as its also brand new, with a new diaphragm, friction plate and so on.

If you find that the engine stutters as you accelerate try using 20/50 engine oil