Trouble starting

[NickJ]

Hi, I'm having problems starting my '72 it has the standard set up except an electric fuel pump, I have gone through various checks, points, plugs, leads etc I have come to the conclusion that there is fuel getting into the carb but not through it. I took out the drain plug on the side of the float chamber and I could here the pump clicking as it filled back up with the ignition switched on. When trying to start it and pumping the the pedal there is no petrol smell as if it was flooding.
Any advice for the next step would be greatly appreciated.

Thanks
Nick.

 

[rob]

have you checked the electric cut off valve in the side of carb body ?

 

[NickJ]

There is power to it but how do I check if it is working ok.

 

[rob]

if working on own with ign on take the feed wire on and off and you should hear it operate.

 

[NickJ]

Ok tried that and I can hear it clicking when I touch the wire to it, tried pouring some petrol straight down the carb and it fired straight away so I think it is defo a fuel issue.

 

[rob]

are you sure fuel is getting into the float chamber ...... there is a needle valve in the top of float chamber which can somtimes stick a bit .......... try giving the top of carb a very gentle tap near the fuel inlet pipe

 

[NickJ]

Gave it a tap still nothing, yesterday I undid the screw in plug at the bottom of the chamber and quite a bit of petrol came out and then I could hear the pump working as it filled up again.
Do you think it is time for the carb to come off for a better investigation ?

 

[rob]

i think your going to have take it off and have a look inside ....... overhaul kits aren,t dear so whilst its off give it a good clean up and blow out the jets etc .

 

[NickJ]

Ok cheers for your help Rob.

 

[rob]

anytime ........ hope you get it sorted soon

 

[NickJ]

Hey Rob, in my frustration I forgot to say "Welcome to the forum"

 

[noddy]

If your valves get tight this also make it difficult to start, also have you checked for a spark at the plugs.

Ian

 

[cyberdyne systems]

Sounds like you have found a problem with your carb.

But to be certain, remove the fuel line from side of carb and turn on ignition with someone holding a container to catch any fuel that comes out. If fuel is being pumped, then unscrew the top of your carb to have a look in float chamber and check its filling up. If it is then by opening the throttle by hand and looking down the top of the carb, you should see fuel spray out, if not then try the clean/rebuild. If fuel is present then you need to look at ignition/compression etc.

Gareth

 

[NickJ]

If your valves get tight this also make it difficult to start, also have you checked for a spark at the plugs.

Ian, Yes I have checked for a spark at the plugs and it's a nice strong white spark.

Sounds like you have found a problem with your carb.

But to be certain, remove the fuel line from side of carb and turn on ignition with someone holding a container to catch any fuel that comes out. If fuel is being pumped, then unscrew the top of your carb to have a look in float chamber and check its filling up. If it is then by opening the throttle by hand and looking down the top of the carb, you should see fuel spray out, if not then try the clean/rebuild. If fuel is present then you need to look at ignition/compression etc.

Gareth

I had the pipe off the carb and there was fuel in that also took the drain plug out of the float chamber then re-connected the pipe aith ignition switched on I could hear the electric pump clicking as it refilled, couldn't get my head over the carb to see in but pumped the carb by hand and couldn't smell petrol, but rebuild kit arrived yesterday so with a bit of luck I may be able to have a go at it tomorrow.

Thanks for the interest and advice I'll update asap
Cheers Nick.

 

[NickJ]

Got the carb off and it seems that I have got water in the fuel :evil: so going to have to drain the tank as well :roll:

 

[rob]

so going to have to drain the tank as well :roll:

hope it wasn,t a full tank

 

[Araon]

How much water?


a bit of meths in the tank helps to carry the water through with the fuel, will run a bit crappy for a while but should get rid of some of the water, used this trick on a few times on old bikes, however if its really high in water content then your as well to pull the tank and clean it.....

 

[NickJ]

There are only a couple of gallons if that much, I took the petrol pipe off the carb and drained that into a pot and this had water in it, took the carb off again some water in the float chamber, when I changed the bellows on the choke mech this has a bit of rust on it :shock: so cleaned it all out and used a rebuild kit on it.
Got it back on the van now but not connected up to the fuel line.
Any water in the tank should be at the bottom shouldn't it ? So shouldn't it come out before the petrol ? The van has been standing for a couple of months so it should have seperated out.
Any more ideas gratefully received.

 

[NickJ]

Well stripped and cleaned the carb, drained the tank and still no starting so fuel cut off valve is next I think although I could hear it clicking when I took the power lead to it on and off.

 

[Araon]

have you tried a syringe of petrol into the carb with the airfilter removed, just get someone to turn it over and try a couple of small shots...