Hinckley Classic Car Show 2017

jonbills

Membership Secretary
Site Administrator
Yes those carbs do seem to be set-up well - your second man did a good job. It ticks over very well and stops immediately when you switch it off too - a novelty for me. I have to stall my blue car and did the same with my old car.


Explain. Just hard to start samuri tick over nice and turn the key off and it will stop[/QUOTE]

It should always start on the button after a couple of pumps of the throttle pedal - if it doesn't, your accelerator pump jets are possibly blocked. (or possibly they're too big and you've flooded it!). If you take them off the manifold one by one without spilling the fuel from the float chamber and pump the throttle by hand, it should squirt petrol a couple of feet.

If it runs on when you turn it off, then you've got something other than the spark plug in the cylinder that's starting combustion - possibly red hot carbon deposits from running too rich.
Fix it with a rolling road session or an AFR gauge and fun hours swapping jets :)
 

Rob Gaskin

Treasurer
Staff member
Site Administrator
It should always start on the button after a couple of pumps of the throttle pedal........

If it runs on when you turn it off, then you've got something other than the spark plug in the cylinder that's starting combustion - possibly red hot carbon deposits..........

Hi Jon, yes with these Webers the car starts really well.

Running-on, I don't think it's as simple as that. I think it's to do with the SU type carbs and high compression engines. Neither of my cars that did it were rich.
 

Mr Ex Jnr

Club Member
Explain. Just hard to start samuri tick over nice and turn the key off and it will stop

It should always start on the button after a couple of pumps of the throttle pedal - if it doesn't, your accelerator pump jets are possibly blocked. (or possibly they're too big and you've flooded it!). If you take them off the manifold one by one without spilling the fuel from the float chamber and pump the throttle by hand, it should squirt petrol a couple of feet.

If it runs on when you turn it off, then you've got something other than the spark plug in the cylinder that's starting combustion - possibly red hot carbon deposits from running too rich.
Fix it with a rolling road session or an AFR gauge and fun hours swapping jets :)[/QUOTE]

I was wondering and wanting to no why he has to stall the car to stop it


There nowt up with Sam apart from needs 're jetting no choke on it so that wat I mean by its a fars to start but few pumps on pedal and it wanting to start
 

jonbills

Membership Secretary
Site Administrator
Hi Jon, yes with these Webers the car starts really well.

Running-on, I don't think it's as simple as that. I think it's to do with the SU type carbs and high compression engines. Neither of my cars that did it were rich.

when you turn the key off, there's no spark at the spark plug. if it runs-on, there's something else in the chamber that is starting combustion, and that something will be red-hot - it is as simple as that. High compression engines generate more heat and so are more likely to heat something to that level - could be carbon, could be nicks on the piston, could be burrs on the piston or head from casting or porting, could be valves worn to a knife edge, it could even be the tip of the spark plug.
I think we've had this topic before - running on is not an essential characteristic of a sporty engine. It's a characteristic of an engine with a remaining opportunity for optimisation :)
 

jonbills

Membership Secretary
Site Administrator
There nowt up with Sam apart from needs 're jetting no choke on it so that wat I mean by its a fars to start but few pumps on pedal and it wanting to start
fair enough. The pump jets on side draught carbs mean you really don't need a choke - you get the cold start enrichment you need from the pumps.
 

kev64

Well-Known Forum User
Rob are you going to donnington park to watch the racing? as im thinking of going and maybe to the Hinckley show too depending on the weather.
 
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