15 replies to this topic

[fin199]

Last year i fitted a stage 1 kit and since the summer had came along i decided id get an Mot on my mini again, whilst taking it a blast down the road i discovered when i put full throttle on it would stutter and there would be pops and bangs from the carb. The ignition timing retards a fair bit then it begins to advance acording to the stobe light, but whilst idling the engine runs on time.

It runs very rich, and the color tune and spark plugs confirm this. It stinks too...

I have been researching and now i believe i have a resistive coil system but a standard coil. So i think the fault might be here. Would my coil be permantly damaged? Will i need a new one and wire it in the standard 12v method? Is this my problem?

I have reinstalled my points because i was unsure if my electronic ignition was at fault.


I find it very weird as the car ran fine last year.

[Cooperman]

First of all change to a directly wired 12 volt coil.

 

The set everything up accurately. If you have a points-type distributor it could well be the bob-weights at the base of the distributor sticking. To check this remove the distributor and strip it down. by taking the points and condenser off, then removing the base plate. The bob-weights can get stuck and require lubrication, especially if the car has been sitting. I had exactly this with an Innocenti Cooper and I took the carbs to pieces, then changed the coil, condenser, plug leads, rotor arm and dizzy cap before checking the bob-weights, which turned out to be the cause of the problem.

[carbon]

Fin - did you disconnect the vacuum advance tube from distributor when using strobe to check ignition timing?

[fin199]

I will check the bob weights. I did put a little wd40 on them when i had it apart but i will look at them.

I set the timing with the vac advance connected. Is that correct? The vac makes quite a difference when its connected and the engine wont run if the timing is set before the vac pipe is connected.

[carbon]

Ignition timing data for strobe is with vacuum advance disconncted.

 

This will make a big difference to your timing.

[gazza82]

Ignition timing data for strobe is with vacuum advance disconncted.

 

This will make a big difference to your timing.

 

And blocked at the carb outlet!

[fin199]

Hi, ive fitted a new coil (12v non ballast) set the timing with a strobe light, vac advance disconnected, 4degrees before tdc, everything is good,but... if you floor the throttle it wont rev up. If you press it gently it will rev. Is somthing sticking?

[fin199]

Somtimes there is a little pop noise from the carb too

[Its a min]

Hi Fin,

Have you checked your fuel mix? I was getting backfire from the carb and found out I was running lean.

[Its a min]

Another thing you may want to check, if you haven't already done so, are the tappet clearances.

 

Hope you sort it.

[timmy850]

Have you checked the SU damper/dashpot oil? Do you have points or electronic ignition?

[fin199]

I do have a colour tune and i used that to set the mix, but i feel it might be too lean indeed? Although the colour tune reads roughtly right. I always think it runs too rich.

The tappets have been set.

I have electronic ignition.

[Dusky]

What engine is it? 4° could be a tad low

[CityEPete]

Do you have an advanced timing strobe or a fixed one? Setting it to around 32btdc at 4000 rpm all in with the vac connected would be better, back it off a touch if it pinks on the road.

How old is the fuel too, if it's from last year forget it, chuck a couple of gallons of super unleaded in before you start tuning anything.

[fin199]

Its a 998cc a+