Dying at the lights

[Sleeper]

Dear All
After a 30 mile spirited drive ( well 60-65 mph on the motorway ) ,came to a stop at the lights and when I went to set off,the engine was just ticking over...no response to the throttle...at the next lights it died but re-started again OK, this had happened last time I took her out and so I cleaned the float chamber ( only specs of crud) checked the main jet and needle and everything seemed OK
Thinking out loud...no venting of the fuel tank causing fuel starvation? but surely I'd notice this more at higher revs?
I know very little of how the carb operates , so , is there something when warm/hot that will stop the needle body ( for want of a better word ) from lifting when the throttle plate is opened ??

Help..

John

[myoldjalopy]

First thing, check you have enough oil in the dashpot...if all was well before, and it happened sudenly, it is most likely a simple fix. Clean the carb piston etc. and also check the fuel pump for delivery....

[kennatt]

its more likely to be fuel vaporization in the pipe from pump to carb,try moving the pipe,or fitting a heat deflector of some sort between the exhaust maniforld and petrol pipe.

[firedrake1942]

Sounds silly, but it is not mentioned in the original post, so worth checking the pump. Is the pump responding to the demand for fuel ? More rapid ticking should be heard. If you are playing with the fuel line. put the carb end in a bottle and see if the pump is pushing the fuel through. If it is, then the issue is further down at the carb or as the last poster says, vaporisation. It has only happened to me once on the M25 and it was a very hot day.

If the pump is not pushing fuel thru, check a) you have fuel in the tank ( Do NOT rely on the petrol guage) and b) give the pump some sharp taps. If no clicking is heard, check the wiring to the pump including the fuses and terminals, things do fall off esp with the old screw on types and they can also be intermittent.

Cleaning the pump points is often a simple solution in this case. In case of the dashpot suggestion, do NOT overfill it.

[Sleeper]

Many thanks,like the vaporisation idea as when stationary there will be no cooling going through the engine bay,as for the fuel pump,it is not electric but mechanical on the side of the block..but will give it a check anyway..

Thanks
john

[firedrake1942]

What model is it ??

[amgrave]

Glad you have said the fuel pump is a mechanical one on the side of the block. In the past there has been a problem with engine heat transferring to the pump and causing vapour lock and you could get a spacer to place between them to alleviate it. I don't know if this is your problem but it fits the symptoms.

[Sleeper]

What model is it ??

'58 4 door,9M-U-H-1xxxxx
FAB1 / 5xxxxx

John

[Sleeper]

Glad you have said the fuel pump is a mechanical one on the side of the block. In the past there has been a problem with engine heat transferring to the pump and causing vapour lock and you could get a spacer to place between them to alleviate it. I don't know if this is your problem but it fits the symptoms.

Looks like the prev. owner had the same problems,the fuel pump looks new as does the in-line filter, a half inch thick black spacer between the block and pump....

John

[firedrake1942]

How common were those pumps instead of the electric / points SU ones ?

[palacebear]

Sleeper: You may want to consider deleting
your chassis and engine numbers from your previous post ... for your own peace of mind

[firedrake1942]

Quite a lot on the forum in the past re mechanical fuel pumps and indeed 1958 Morrises are mentioned. It seems to be that some Minors had A series engines that were closer or perhaps intended for / transplanted from Austins which mainly had mechanical as opposed to SU electrical pumps. At least that's what I gather from the posts.

[Sleeper]

Sleeper: You may want to consider deleting
your chassis and engine numbers from your previous post ... for your own peace of mind

Will do

Thanks
John

[Sleeper]

Dear All

Looks like the dash-pot is short on oil,could that be the cause?

John

[myoldjalopy]

I did suggest checking that earlier. Not enough oil in the dashpot will mean hesitation and cutting out on trying to accelerate......fill up to the correct level and see if it makes any difference.......easy check to do.

[Sleeper]

Yes,sorry,thought i'd checked that last time I cleaned out the float bowl etc...bit busy at the moment but will report back..

John