5 replies to this topic

[nospamprl]

I own a 998cc Mini 30.

My mini was running great but I felt idle speed was a little too much (tach @ 1200 rpm).

So I reduced it to about 900rpm by adjusting the idle screw on the carb ( I didn't touched the fast idle).

Since then, I feel the engine runs erratically specially when cold and hesitates under acceleration, when it's very hot it runs fine.

So I turned idle speed up again, maybe a little too much. And it got worst.

I thought idle speed had nothing to do with hesitation, but it happened when I adjusted it.

Do you think hesitation is related to this adjustment or may it be another problem that appeared by coincidence at the same time?

I'm not willing to mess it up by myself. So if it's something else I would take it to the mechanic, and I don't want to unless there's no other easy solution.


Thanks

[carbon]

Do you need to use the choke to start the engine, and if so then how long before you can stop using choke?

[nospamprl]

Yes, I use it for about 30 seconds to 1 minute. I live in Mexico and it's not really cold here.

[Retroman]

I would think it might need a new needle and main jet to restore the mixture back to where it should be, the idle should then be back to normal too.

 

They wear and it causes all sorts of tickover and mixture issues.

[carbon]

+1 for Retroman's suggestion about wear on the needle.

 

They are quite easy to check, take off the dashpot (3 screws, but make sure this piston does not drop out and get damaged) and check along the length of the needle for a wear ridge, normally this is about 3mm from the lower face of the piston where it rubs against the side of the main jet.

 

If it is worn then SU Burlen have just about any needle off the shelf. Minispares also hold a good stock.

[nospamprl]

Well, after a good 30-mile run on Sunday at highway speeds, the hesitation disappeared at least when hot. I parked the car and lowered again the idle speed.

Yesterday I took it for a test drive and hesitation is gone both cold and warm.

Seems that the problem was only related to idle adjustment.

Thanks everybody for your help.