10 replies to this topic

[Baz]

Hi all. I'd Welcome any thoughts on why my engine has suddenly refused to run. I took my 1990 cooper out on a run today it drove great for about 5 miles. I stopped to take some pictures of the car by the river. I Got back in, it started but then 100 yards up the road just lost all power. I got a tow home and have checked the fuel pump working fine, pull the choke out and the engine will idle fast put choke in it struggles for a bit then stalls. I'm baffled so has anybody had a similar issue? Cheers

[MiniMadRacer]

Partially blocked Carb jet maybe...

[cal844]

Check there is no detritus in the carb jet and float.

do you have a fuel filter fitted? If this hasn't been changed in a few years you'll have issues.

How much fuel is in the tank? How old is the fuel?

Do you have a spare coil or even better is a friend with a running mini who lives nearby you could borrow parts from to diagnose, then once you find the fault return the parts used.

I suspect it's either a blocked jet tube, or a piece of detritus in the carb, remove the dash pot assembly and blow down the jet, ideally you'll want to remove the float bowl lid and drain the float bowl(small syringe or use some rags) before you blow the jet through. You only need 40-50psi.




You want to remove any sediment from the bottom of the float bowl then rebuild and top the dash pot oil up.

Start it up and check for leaks, now run the car and see how she goes.

If the fault hasn't changed try a coil from a known working mini on it.

Edited by cal844, 03 June 2020 - 09:47 PM.

[Baz]

Thank you this is really helpful. I can take the carb off this morning and clean out as suggested. The coil is new and I had filled up recently so don't think this is the issue. Reckon it's muck in the carb causing a blockage.

[pete l]

Check all pipes for a split, an air leak and it won't drive.

[cal844]

Thank you this is really helpful. I can take the carb off this morning and clean out as suggested. The coil is new and I had filled up recently so don't think this is the issue. Reckon it's muck in the carb causing a blockage.

If it's an HS2 or HS4 carb, You wont need to remove the whole carb, (that, ofcourse is upto you) as you can blow the air through the jet assembly by simply removing the three screws on the dash pot, and the three screws on the float bowl lid.

Remove the fuel from the bowl and blow through from the jet where the needle sits into. Remove any debris from the float bowl and rebuild, remembering to top up the dash pot oil.

Hope this helps

Cal

[andyapanel]

It could also be a sticky carb spring. If it is not letting the needle move properly, then you could suffer fuel starvation which you could rectify with the choke.

 

+1 for fitting a fuel filter if you have not got one.

 

Good luck

[big john]

Remove the cap for the petrol tank and see if full power returns. Could be a plugged tank vent line.

[Baz]

Well guys,thank you for all your input. The car is now running fine. One piece I forgot to mention the car had been in for its MOT. Seems to get it through the emission test the garage backed the mixture screw right out so it was running so lean it wouldn't pull. In the end a simple fix but really baffled me for sometime.

[cal844]

Well guys,thank you for all your input. The car is now running fine. One piece I forgot to mention the car had been in for its MOT. Seems to get it through the emission test the garage backed the mixture screw right out so it was running so lean it wouldn't pull. In the end a simple fix but really baffled me for sometime.

That really is a nightmare, I will send a PM to your inbox for a little cheat...

[andyapanel]

Its always good to hear a solution.