360 GLE Solex carb fuel cut off valve

Does anyone know anything about the fuel cut off valve on the Solex 34-34 late carb on the 1988 360 GLE models. This is not the idle solenoid but another one which I think needs energising to allow the fuel to flow. I had a non starting problem today and no fuel could get into the carb. I dismantled the inlet pipe where there is a small filter (inside the carb not the in-line one lower down), then I poked up insde the carb with a bit of wire and then the car started. Not quite sure how to get to the valve and clean it. The latest Haynes manual for the 300 series only covers the 34-34 CISAC carb without the fuel cut off valve, so it's no help.

[pettaw]

I suspect that there might have been a small bit of grit that has got into the carb filter and blocked the crucial bit. Poking it with the wire probably cleared it.

As far as I know, and I'm not really that familiar with the carb 360's having only an injection one myself, there is only one cut off valve. However, it's easy enough to tell, because there will be a wire for its electrical connection. You should hear the valve 'click' upon connection and disconnection of the wire.

Hope that helps.

Andy

Andy

Yes, you may be right about the grit. This carb certainly seems to have two of something as there are two wires going to the carb, the idle solenoid certainly clicks when connecting it with the ign. on but when connecting the other one I could not hear anything. This is why I suspected a problem in that area. All I know is that it is mentioned as a fuel cut off solenoid in Haynes manual, but there are no other details. The trouble is I think they call the same thing the "idle solenoid" the "fuel cut off solenoid" and the "idle jet cut off solenoid". I am beginning to think you are right and that there is only one solenoid. The other wire may be due to the "pre-heating system", whatever that is. It is again referred to in the manual, but no details of it are given. My understanding of the first solenoid, call it what you will, is that it was intended to stop running-on when the ignition was turned off, (which it does not seem to always be effective at). Anyway, the car is running OK at present.

[pettaw]

All of the fuel cut off solenoids look similar, a barrel shaped thing with an electrical connection to it. If your carb has an electronic preheater then this will look quite different. It might just be a plastic housing covered by a screw with what looks like a connector going to a metal plate.

Basically the electronic preheaters are a piece of resistance metal that when connected to a supply get hot. They're normally attached to the carburettor base, somewhere near the idle circuit of the carburettor, and their function is supposedly to smooth out the idle in the first few minutes of warm up and to help stop icing. The older ones worked on engine coolant flowing round the baseplate, but as in the way of things, technology changed and these electronic ones were invented.

If you have a resistance meter, then you could disconnect the electrical connection and check the resistance, it should be about 10-20 ohms or so. If not it doesn't really matter that much, as long as your car is running well, I'm sure it'd be OK.

Andy

Yup, I'm now sure there is only one cut off solenoid and that's the one that looks like one, as you say. I did measure the resistance of the other lead to the carb yesterday, I think it was about 35 ohms, I just wanted to make sure it was not open circuit. I'm sure this is a pre-heater although it was hard to see where it went, somewhere below where the throttle a choke linkages connect.

I think as you say it was a piece of dirt, that I shifted just near the filter in the inlet pipe. The car went fine today - 50 miles driving.

Thanks for all the help.