fuel system

Got a White 2-105 tractor. had it about a month. Using it Monday and it ran out of fuel in lower tank that is in front of the right axle housing. After inspecting the system set up, I turned on the upper tank and let that fuel in the lower tank. It took a lot of priming of the pump, but finally got it started. Now, it is hard to start every time. Is this the way all the 1955 Olivers and White 2-105's were plumbed, to pull of each tank individually and you have to switch the tanks back and forth? Has anyone ever put an electric pump between the tank and the pump on the engine? Just trying to get educated on the unit. I have a parts manual and owners manual ordered. Nice tractor and I enjoy using it, what little I have; just a few squirelly things happening.

1955 & early 105 pulled out of the top tank and created partial vacuum which drew fuel out of the fender or lower tanks. Late 105 drew out of the bottom tank and gravity fed the lower tank. My guess is the some part of the original system failed and the prior owners "field expedient modification"'d it. When the factory system failed on our 2-150 we F.E.M an electric pump to refill the top tank when it got down, eliminating the vacuum system.

Is the supply pump on the block side working right? They do go bad after awhile, usually the internal check valves come loose. Just replaced the neighbor's 2-85 pump that died..

There were two fuel tank systems used on early and later tractors.

The early version had a non vented cap on the upper tank and a vented cap on the lower tank. You would fill both tanks through the cap opening on each tank. Then the upper tank syphoned fuel from the lower tank to the upper tank as it was used by the engine. A fuel line from the bottom of the upper tank fed the fuel pump on the side of the engine and then to the fuel filters and injector pump.


In the early version if there were any vacuum leaks in the lines between the upper and lower tanks the fuel would not be syphoned to the upper tank and you could run the upper tank dry but have fuel in the lower tank.

It is important to remember this early system had two fuel caps and it is very important to make sure you have the non vented cap on the upper tank and the vented one on the lower tank. Mixing them up defeats the system. Also the upper cap must seal properly for it to work as well as every connection in the line between the two tanks. Sometimes the gasket on the non vented cap would deteriorate due to usage and the system would not work.

The later version had a vented cap on the upper tank and no cap on the lower tank. When you fueled the upper tank it filled the lower tank through a large line from the bottom of the upper tank until both tanks were full. The fuel pump would draw fuel from the lower tank.

You can overcome the syphoning issue by putting an electric fuel pump in the line between the upper and lower tank and pump the fuel into the upper tank from the lower tank as it is used.

Just a question, is there a rebuild kit for the fuel pump on the side of the engine or do you have to replace the complete pump? The manual describes rebuilding the pump with a kit.

I installed that change over deal on my 1975, 2-105 back in 76-77 and everything has worked great, no gauge on lower tank was the only drawback, but the square "O" ring in the lower tank cap with the 2 hoses deal failed this spring and it is still available thru AGCO parts and I was surprised. I need to replace the lower tank supports as the rubber deals are worn out. Agco parts has them also for about $40.00 each if memory serves me right.

probably debris, start at the tank and work toward the carb. It took a lot of priming because of the low flow, that's good, some where in between. Last guy had this problem found it in the fuel pump. I've always found it in the neck, between the tank and the bowl. Dirt, leaves, crops all get in there over the years. Add to that a machine that sets for spells, a condition that creates moisture and the tank deteriorates, flacking off sitting there till the fuel sucks it into the neck.

I don't think an electric fuel pump is needed, just think about the pressure x number of gallons has. The blockage could be between the tanks.

Mine I'm told holds 45 gallons, if a gallon is around 8 pounds, using some rough math that's 370 lbs when full. Same principle as a water tower, just think how much pressure that thing has. Feeds an entire area and I don't think it pumps out, just in.

Clean it out and you'll be good as new, or as it can be. I'd replace the pump, cheap maintenance.