Running to long
Turbo Mini Forums

It is running again now, fuel problem is sorted
Now when I hit the throttle it revs up, if I release the throttle it keeps revving a few seconds and than returns back to idle again.
This is to much to accept, I want it back to idle a lot quicker.

What will this be?

sticky throttle cable? or maybe the return spring is weak.
DAN :)
but then sod's law says its gonna be more complicated than that :(

Trottle cable is long enough.
Butterfly thingy is soldered shut.
With or without turbo pressure same story.
Pressure reg set at 4PSI.
Engine running superb.

I have a feeling that the big piston in the carb is to slow closing.
with or without oil in the dashpot, no difference.

HELP

Could be an air leak, post carb. If you have a servo, then check that the diaphragm is not porus and that the one way valve is working. Failing that, if you still have the breathers sttached to the manifole, chekc the one way valve there as well. Petrol vapour can degrade the diaphragms on some.

Is it only when the engine is hot ?
The turbo carb has a swinging needle arrangement and this *can* (but slightly unlikely) cause too much friction between the needle and jet, resulting in the piston dropping slowly, or jumping. if the meedle is notched, this can also happen. As you swimg the throttle shut, it goes from pressure to vacuum, which can suck external air in and weaken the mixture when the throttle closes.

Just wondering what you mean by butterfly thingy...

I could find a leak with some wd40 cant I?, I have no servo or anything other vacuum things other than the boost gauge connected to the manifold. I have however an extention between the carb and manifold.
This happens when de engine is cold and when its hot and it very consistend.
The butterfly thingy is the hole with the little valve and spring in the butterfly, this is soldered shut.

Disconnect the throttle cable at the carb. Get your hand on the throttle inkage at the carb and rev it up with your hand, then snap it shut. Can you feel it closing securely with your fingers? What's it doing now?
If the throttle is indeed shutting securely, then it can only be an air leak, or that the disc is not seated correctly I'd have thought...

Alright, the butterfly didn't close. I seems ofset to the shaft and I turned it upside down and now it closes. PROBLEM SOLVED
How many turns do I loosen the mixture screw as a basic setup to a standard metro lump?
I want to take it from here.
Its revving up real fine now and de-revving also. responding like a stamper in a ladys hand.

I had my first test real runs today after fitting a new gearbox.
It seems to have a loud knocking when comming on boost, its getting louder when the engine is warm. What will that be?. ignition is set to 20 deg advanced and having no vacuum to it.
The car runs very very nice and very very fast, apart from the knock it seems fine. It has the standard setup from a metro turbo, bolted to a high compression block. running at 4PSI.
Anyone?

arno what dizzy is fitted to engine

A bogstandard mg-midget one with breaker points

i take it the same dizzy as cooper s it got no vacum advance fitted

you sure about the advance - ie checked the TDC reference to actual TDC?

so its a advance problem, thats what it sounds like the most.
I shall check the TDC mark hopefully today.
It has a vacuum fitted but not connected, should I?
I think I am on the right track now, just hope it didnt damage.
Thanks for thinking with me