9 replies to this topic

[hatchet]

Had some chap come to look at my Cooper the other day but as it was running so poorly he understandably didn't want to buy it! :nugget: He's left his number as he would like to see it running properly.

The problem is that it starts and idles ok, but when opening the throttle quickly it fluffs and sputters. It doesn't mind too much when opening the throtle in small increments. The only thing that I have done since its been off the road is remove and replace the exhaust. There is a very small leak at the y-piece and link pipe join, would this have the effect as described. Or the back box may need replacing as it is now very noisy, could this also affect the running?

Or would it more likely be a fueling issue (fuel pump possibly)?

Cheers
'Abbo'

[Pooky]

I've had this problem but only when i stop in traffic after a long journey!

I've always thought it was fuel and i've read that putting a fuel filter in the line helps!

I've also heard that it could be the hot manifold evaporating fuel in the float chamber or something?!

[Jackman]

Mine does that when its cold, even in hot weather. Dont know why, need to start with choke.

[Jammy]

Hmmm, could be something to do with the oil in the dashpot or something? Maybe the piston in the carb is being allowed to raise and fall too quickly, so when you open the throttle quickly, the car runs too rich!?

[Bungle]

Hmmm, could be something to do with the oil in the dashpot or something? Maybe the piston in the carb is being allowed to raise and fall too quickly, so when you open the throttle quickly, the car runs too rich!?

sounds about right , have you checked ?

[Purple Tom]

i think its the other way round.

Sounds like its running lean to me. But I think Jammy could be right about the dashpot, it sounds like it could be a combination of the dashpot needing oil, and too weak a mixture.


Does it run better when its on choke? If it does then it almost certainly us running lean.

[Jackman]

It runs fine when on choke but when it warms up it runs fine again, also im using the proper su oil, should be getting it on a rolling road this week tho to get my emissions down from 7.77 to the legal limit lol.

[Jammy]

Well it sounds like your problem would be sorted with a rolling road.

[Purple Tom]

if it runs fine on choke then its almost certainly running too lean when off choke.

like Jammy says get it rolling road tuned, will make a huge difference.

The same goes for hatchet too!!

[Gaylord Focker]

miniman5 here on gay lords acount,(he is sitting next to me)


i would say that its running slightly lean if it runs ok with the choke out.