How does the Kubota BX fuel tank vent?

[Jon Baughman]

I've been to a Blow Mold factory and watched the process of making water tanks. When the plastic is drilled to install something, there is flash (shavings) inside that need removed.

I've read of many problems coming from BX owners who've completely removed the fuel tanks to find shavings and plastic remnants. That's enough validation for me to feel the quality control regarding the issue is nil to none.

I've also seen images of the low quality fuel sending units that are used, covered in rust. Rust draws moisture and creates a breeding ground of more problems.

I am very sure that the fuel tank outlet is not clogged with debris. When I wiggle that fuel pump line off, fuel will just gush out of it.

 

[Jon Baughman]

Update;

Over the late fall and winter, I have continued to experience the same engine shut down.

The symptoms are the same; tractor chokes off and won't start, I can't hear the fuel pump pumping fuel, and when I release the vacuum on the inbound fuel pump line the tractor starts and runs perfectly.

This spring I will post pictures. My son-in-law is a mechanic and has a bore scope for fuel tanks and I will be able to view the inside of the tank to determine if there is debris or not.

I did watch a youtube video where a bx owner removed the fuel tank to clean it out only to discover that it was not dirty. He did discover in the disassembly that the outbound fuel tank line had developed a kink in it from being routed over a pinch point. That kink in his line caused the same symptoms that I am having.

I will try to evaluate that next.

 

[whitetiger]

You have debris in the fuel tank that is blocking the fuel outlet fitting which creates a vacuum in the fuel hose between the pump and the tank. When you remove the hose from the pump suction fitting, it sucks in air which is dislodging the obstruction from blocking the tank outlet fitting. I have seen this scenario several times.

A simple test is to run a piece of fuel hose from the outlet of the secondary filter to the fuel tank fill opening and turn the key switch to the run position to let the fuel lift pump circulate fuel for a while. After a while, the flow will lessen or stop completely which will show that it is obstructed. Also, with the cap off it will rule out the cap vent being obstructed.

 

[GreensvilleJay]

Here's what finally chug,chug, stopped my BX23S It's a tiny, crescent shaped piece of plastic that wedged itself into the 'exit' spigot of the tank. The spigot is maybe 1/4" ID and this was inside it ! Due to the 3 chamber design of the tank and this being black,same material it was impossible to see. ONLY after I removed the tank,blew air in via spigot did water flow out ,so I KNEW 'something' was in the tank. I took a very leisurely 3 days to remove/clean/replace the tank. Help to remove seat and fender pan would have been nice...otherwise an easy job. I've upgraded my 'sink strainer' to a 'cold press mason jar' filter this year.