The Fordson Tractor Pages Forum

I have just finished rebuilding my Dexta after a paint job and when I came to turning it over it was hydraulicking. All cylinders had diesel in them and No3 was full to the brim.
I took out all the injectors and left the fuel turned on - no fuel came out the injector pipes or spill lines.
I checked the diaphragm on the fuel pumps and when I opened the diaphragm housing about a tablespoonful of diesel came out. The pump side of the diaphragm was dry and oil free.
I sucked all the oil out of the cylinders, connected the injectors and ran it up. As you would expect it was a bit smokey at first but quickly ran cleanly. At this point the engine started to race (I can't tell you the engine speed, because the taco cable is still disconnected) When I pulled the stop lever it had little effect and the only thing that brought the speed back under control was shutting off the fuel until it slowed and then I could stop it on the stop lever.
The fuel rack moves smoothly and the line from the diaphragm housing has been checked and is in good condition.
Nothing mechanical was done while it was stripped for shot blasting / painting and it ran fine beforehand.
It is looking great in its new coating, now all I need to do is get a little help in getting it running properly. I just can't figure out how fuel is running into the cylinders, and how did some of it get into the diaphragm housing?

I think I may have figured it out with a bit of overnight thinking. My feeling is that the pump that feeds the cold start might have failed and fuel is flowing from the tank through the pump into the air manifold and then into the cylinders. This is the only explanation I can come up with as to the diesel I found in the vacuum side of the diaphragm housing. I have a new unit on the way and hopefully that will be the end of the problem. Anyone else seen this kind of failure?

That's the only reasonable cause, pop an inline tap into the cold start feeder pipe as a quick fix to get you going whilst you sort a tap repair out.

Thanks russelm, I think fitting a tap would be a good precaution. I'll fit one once I have the new unit fitted

I've now fitted an new unit and the old Dexta is running as sweet as ever -- happy days