So I've alleviated the fuel pump now what can be wrong?

[alvera]

I agree that it could be caused by having a non vented petrol cap fitted. Several years ago when it was very cold I had a similar problem and I my assumption is that I had ice form and block the vent path. When I took the cap off I could hear the air rushing into the tank and the engine started up once again.

I will attached a picture of a locking type cap stripped down so that you can see the vent path. There is no hole to see, there is a slot cut under the rubber seal and up the side. Very crafty. If you look carefully with the rubber seal in position you can see the slot up the side.

Thanks for the pictures etc.
I checked the non locking cap today and everything seems fine, I also checked the fuel line from the tank and didn't find anything wrong.
I removed the coil today and it seems an original as it is a Delco one. I shook it and it doesn't seem to rattle.But the ballast resister is missing and there is a lot of wires connected to each other. Alan

[alvera]

So I have decided to replace the rubber parts of the fuel line, blow the line back to the tank, and fit a fuel filter after that I will check the carbs float etc.Then when after all the checks I will take some tools and go for a drive and see what happens. That way I can alleviate the fuel except for the tank, but at least I will be able to see if the pump is sucking muck out of the tank and if that happens I will have to clean out the tank.By having tools with me I can then check the spark and replace anything needed and hopefully I can get back home without a breakdown service.
Thanks for all your suggestions, it's very hard when in the garage it runs perfectly.
Wish me luck Alan