Carter W1 empty itself quick

[Phil Waterman]

Hi

The Hand Throttle and Choke are operated by slide cable from the dash. These pictures show how they connect to the carb



For higher resolution photos go to http://canadianmilitarypattern.com/R...mera%20045.jpg
and
http://canadianmilitarypattern.com/R...mera%20046.jpg

More engine photos from my HUP project http://canadianmilitarypattern.com/H...INE%20WORK.htm

Glad you found the source of the fuel leak, the slow priming is one of the reasons I have gone over to electric fuel pumps. Was very interested to hear that you are using some high tech tools to tune the engine. You will have to tell us more about this as your project progresses.

Cheers Phil

[david moore]

I have the same sort of problem as mentioned here - my jeep is very slow starting after being left even for an hour or so. I can help it with a spritz of gas into the top of the carb (its a Solex in this case).
I'm wondering if the fuel cap is supposed to have an air vent? Mine doesnt. My logic is that, if sealed, there will be a partial vacuum in the tank after running - which could suck back fuel to the tank. Or is this not possible?

Or could it be that the timing is a bit off? I never know if it needs to be a shade more advanced or retarded for easier starting. I also dont know which way to turn the distributor head a little for advancing or retarding.

Comments welcome!

[motto]

Fuel cap venting has been a topic of some discussion over the years and is often misunderstood. Basically, a fuel tank cap must have venting unless the venting is provided elsewhere. Having said that, the fact of the matter is that on a hot day no venting is needed as the fuel vapour will pressurise the tank anyway. After all, a LPG cylinder does not require a vent to expel it's contents, vapour pressure does that. The difference is that LPG vaporises at a much lower temperature than petrol.

I once put a jerry can in the sun and it went up to 3 psi which is fairly close to fuel pump pressure. The standard WW11 4" cap used on GMC, Jeep, etc. had a relief pressure of around 3 psi and this was not without reason. On hot days, this pressure in the tank helps prevent vapour lock which, as we know, can immobilise a vehicle.

Cold conditions are a completely different ball game. We've all seen jerry cans with the sides sucked in that had been filled in warm conditions and then subjected to cold. Your fuel tank will do the same if not vented and this is made worse if fuel is being removed from the tank. For this reason, those 4" caps that have the 3 psi outwards relief also have (if I remember the figure correctly) 1-1/2 psi inwards relief.

In summing up, for cold climes, a simple vent hole in a cap is sufficient. For hot climes, a pressurised tank through use of a relief valve is a definite advantage.

David

[patallen]

given the short time you mention that the jeep is reluctant to start, i would say, from experience, vapor lock. it wont be the first time i hear about fuel boil into the carb on a jeep once stoped after a ride.
fwiw make sure there is a heat insulator under the carb to isolate it from excess heat.