Fuel line problem.

[Richard the old one]

I recently purchased a dolomite that has not been on the road for over ten years. The previous owner was left it by a relation and had intended to put it back on the road but after having it for a number of years decided it had to go. He had started doing various bits but had not finished anything, so there were no clutch or brake hydraulics and he had removed all the rubber hose sections that join the fuel line together.

As I was interested to hear what the engine sounded like, so I cleaned the build in filter on the petrol pump. This was not very dirty and I initially ran the car using a petrol can and a length of hose. I was surprised how quickly it fired up after 10 years.

The petrol tank had been drained and I took it out to check it over for rust and to give it and the area under it a coat of Waxoil. I then set about replacing the rubber hose section something I have done a number of times before on my other dolomites over the years. I took care to ensure that the connections were tight and I also checked the metal pipes as best I could while they were in place. When I turned the key I expected the car to burst into life once again after a short period. This did not happen and when I checked by taking the hose to the front carb off there was no petrol in sight. Next I checked at the petrol pump. Again it was dry but I could blow through to the petrol tank. I then started disconnecting the various rubber hose connections starting at the tank. There was petrol here but not at any further forward initially. I resorted to taking out some of the pipes and blew through them but they all seemed clear and I could not find any pinholes in them. Finally I did get petrol to run out of the first connection under the car back from the pump and I collected almost a gallon in a petrol can. I reconnected the rubber hose and attempted to run the engine again but it still would not start due to lack of petrol. I was now thinking that the pump must have failed and to prove this I once again connected the pump direct via a hose to the can of petrol that I had collected. When I turned the engine over it fired so it was not the pump! I now once again connected the pump to the petrol line and much to my surprise it worked this time.

As you may have guessed this took up most of the afternoon but I just can't explain what caused the problem. Has anyone else had this problem and can anyone please come up with an answer.

[Jon Tilson]

Pumps do like to suck air, so if you had the merest hint of an air leak on any of the sections you joined it would be enough to stop the pump sucking.
I'm guessing your pump had partial gravity assistance from your can arrangement, which is a great way of preventing air leaks, so then it was happy.

When it comes to a completely air filled fuel line your poor old pump has a LOT of sucking to do. A good tool is one of those hand squeezy pumps that the AA men use.
Stick that on your fuel line and see what happens. The trick is to get fuel nearly up to the pump and then it will do the rest. In situations like this there is a lot to be said
for the old moggie thou style SU electric pump.

Jonners

[Richard the old one]

Hi Jon.

The petrol can was on the floor.

It was just so frustrating and I wasted a lot of time and effort. I did attempt from the start not to have any air leaks so I will look into getting a hand pump as you suggest.

[Jon Tilson]

Just wondering if at times you had the pump fitted so the lever was under the cam?

I dont ever recall this happening to me on an ohv but it has a few times on various slants.

Jonners

[Edin Dundee]

I was always told to prime a pump with oil when refitting empty, gives it something decent to suck on.

[Richard the old one]

For info. I did not remove and replace the pump at any point in the afternoon.

I am just glad that the car is up and running once again and hope that the advice given will help others members if they have the same problem.