4 replies to this topic

[aircoolednut]

HI all, me again

1990 Mini city 998cc, cleaned and checked carb, fuel pumps works fine, fuel gets to spark plugs. New contact breakers set to 0.35mm, new spark plugs set to 0.8mm, new condeser, new HT leads, new rotor arm, new distributer cap, new battery and nice blue spark, so why does it run rough, occasional misfire or chug chug and it needs to idle at more revs than it should.

OK so what next, I dont know? I do have a dwell meter, but not sure how that works.

the engine was runing fine, but as usual I decided to improve it and thought I would change things make it sweeter, but aaaagghhh yes, the ungifted amateur struck and I **** it up. I have tried to check and clean all connections etc and all seem ok.

Well that is about it really, any gifted suggestions that I can understand will be truly welcomed.

many thanks

Aircoolednut

[stickycreambun]

Hiya.

Do you have, or cold you borrow a compression tester? Also, did you change the condensor too?

[Retro_10s]

if you have definately ruled out all of the electrical reasons for it to run roughly,.. then it is time to suspect the fuelling to be at fault. What is it idling at,.. a standard 998 engine in good health should be able to sit at about 600rpm when warm.

[aircoolednut]

The dam thing will not tick over with out revving it, it sits there going chug chug chug if I push in the choke, I have checked the idling speed adjuster and it also misfires, not ofton, not big time, just does, still reckon something screwy, not sure about contact breaker gap, set it to 0.35mm, but Haynes not totally clear on that one for a 1990 mini.

[Retro_10s]

AS I said, if you're sure it's not electrical... then the fuelling could be suspect....I believe (although there are quiet a few possibilities) that misfiring is usually caused by Under fuelling,... which would also explain the Idling problems you're getting...