24 replies to this topic

[Little Miss B]

So I'm having troubles with my Mini's engine, she has recently started juddering when the engine is put under load.

As a quick summary, she is a 1987 City, with a 1330 engine (stage 2 rally kit), the problem appears most when in lower revs within each gear, once the revs get high enough she smooths out, especially within 4th gear.

It does appear to be intermittent, when taken on a recent 200 mile round trip there were points where the problem would all but disappear when cruising on dual carriageways/motorways.

My first guess was a fuel related issue, as it seems that when under load not enough fuel is getting through (causing judders and lessening of performance at the same time), possibly carburettor?
My other guess was whether the alternator was struggling, as she has recently started struggling to start up, when previously she would on the first attempt.

Has anyone else experienced this and know what it might be. Any suggestions welcome as I want to avoid lengthy expensive garage time to work out what the problem might be??

Many thanks
Emma

[Kam]

Do you mean the engine is stuttering and spluttering as in fuel related or juddering as in engine mount related? I'm guessing the latter?

Theres a couple of thread about the engine mounts.....I'll have a look....

[Little Miss B]

Thanks, its the former ... the engine is stuttering, spluttering when under load, but when not the engine is stable so I wouidn't think its the engine mount (this was also looked at fairly recently and all was fine)!

Do you mean the engine is stuttering and spluttering as in fuel related or juddering as in engine mount related? I'm guessing the latter?

Theres a couple of thread about the engine mounts.....I'll have a look....

[Kam]

Stuttering and spluttering under load would be fuel related, which could be a number of things

If when you accelerate and back off and hear a knock/judder then that would point to mounts, to check the mounts you could try pushing and pulling the engine yourself when cold and see if/how much it rocks, then start it up and get someone to operate the pedal and check it like that

Fuel wise, there might be someone along shortly that knows a bit more! You could top-up the carb dash pot though and see how that fairs? They get forgotten about easy and will cause stuttering under load if not topped up

[Little Miss B]

Thanks for this, I'll check the mounts and try and rule that out for starters.

I've heard about the carb dash pot before, I guess I should check that too. Hopefully the fuel experts will be able to give me some more tips too

Stuttering and spluttering under load would be fuel related, which could be a number of things

If when you accelerate and back off and hear a knock/judder then that would point to mounts, to check the mounts you could try pushing and pulling the engine yourself when cold and see if/how much it rocks, then start it up and get someone to operate the pedal and check it like that

Fuel wise, there might be someone along shortly that knows a bit more! You could top-up the carb dash pot though and see how that fairs? They get forgotten about easy and will cause stuttering under load if not topped up

[pikey7]

if it's relatively recent, and you haven't messed around with the carb settings, then i reckon it's electricals. dizzy cap, rotor, points, HT leads, LT short, coil, plugs. It may *sound* like a fuel issue, but if you are getting a bad spark, then it will change the size of the bang in the engine.

Replace the cap and rotor, adjust the points and clean/replace/gap the plugs and see where you are.

[Little Miss B]

if it's relatively recent, and you haven't messed around with the carb settings, then i reckon it's electricals. dizzy cap, rotor, points, HT leads, LT short, coil, plugs. It may *sound* like a fuel issue, but if you are getting a bad spark, then it will change the size of the bang in the engine.

Replace the cap and rotor, adjust the points and clean/replace/gap the plugs and see where you are.

The carb had been played with for the MOT and afterwards and the spluttering/struggling to start began after this.

[Little Miss B]

Also forgot to mention that the plugs/points have been checked and are in a good state

[MiniJosh92]

if it's relatively recent, and you haven't messed around with the carb settings, then i reckon it's electricals. dizzy cap, rotor, points, HT leads, LT short, coil, plugs. It may *sound* like a fuel issue, but if you are getting a bad spark, then it will change the size of the bang in the engine.

Replace the cap and rotor, adjust the points and clean/replace/gap the plugs and see where you are.

The carb had been played with for the MOT and afterwards and the spluttering/struggling to start began after this.

This would indicate that the mixture was adjusted to get it through the emissions test. It probably just need re-adjusting to get it to run right.

[Gulfclubby]

Also forgot to mention that the plugs/points have been checked and are in a good state

Timing hasn't been changed either, has it? Is the dizzy tied on properly?

[Little Miss B]

if it's relatively recent, and you haven't messed around with the carb settings, then i reckon it's electricals. dizzy cap, rotor, points, HT leads, LT short, coil, plugs. It may *sound* like a fuel issue, but if you are getting a bad spark, then it will change the size of the bang in the engine.

Replace the cap and rotor, adjust the points and clean/replace/gap the plugs and see where you are.

The carb had been played with for the MOT and afterwards and the spluttering/struggling to start began after this.

This would indicate that the mixture was adjusted to get it through the emissions test. It probably just need re-adjusting to get it to run right.

Yep the mixture was adjusted for the emissions test as before she was running rich and did always start first time which no problems. I did think it could be this but a 'friend' told me otherwise, mentioning alternator and electrical issues which confused me. I will try adjusting it back this weekend.

[Little Miss B]

Also forgot to mention that the plugs/points have been checked and are in a good state

Timing hasn't been changed either, has it? Is the dizzy tied on properly?

Timing is a tricky issue. She has no vacuum advancer so the timing is adjusted by hand. However, the timing she is set to in theory she shouldn't even be driveable with, its possible its slipped though.

[Kam]

Not sure whereabouts you are but maybe run it round to carl at fastparts in croydon, might be someone closer where you are but he loves his minis.....

http://www.talkaudio...d.php?p=3577355

Hth

[Little Miss B]

Ok so an update.

The mounts have been checked and are all fine, they were recently tightened before the MOT.

The plugs are fine.

There is some occasional smoke in the lower gears but this is irregular.

Do people still think this is a fuel or electrical issue? I still need to play with the fuel mix.

I appreciate any feedback, many thanks!

[Kam]

Does this only happen when its raining or generally damp? If so then that rules out fuel!

Carbs been played around with aswell so go with that first