Long 310 loss of power/rpm problem solved

bladerunner3 · Nov 13, 2009

While using my Long 310/260 last weekend, the tractor began losing power, running slower and slower, until it would just quit. After sitting for a few minutes, it could be started back up, run for a little bit, then it would start slowing down again and finally just quit. This tractor has been sitting for a long time before I got it, and I suspected a fuel starvation problem due to junk coming from the tank and lines. I had just changed the fuel filter earlier that morning. I was getting plenty of fuel up to the injector pump. Taking the input fitting out of the pump, I found a small screen filter, gobbed off with black junk. I sprayed it off with the only aerosol spray I had handy, a can of starting fluid. It did the trick. After re-installing the screen filter, the tractor started up, made full rpm, and ran perfectly for an hour or so, then began doing the same thing it was doing previously. Checking the screen filter revealed that it was again gobbed off with black junk. After the second cleaning, I haven't had to clean the filter again, but will probably have to in the future. Here's a link to a rebuild manual showing the parts of one of these injection pumps-go to the last 2 pages of the manual, the filter is part no. 10:
http://www.fujiyachts.net/manuals/CAV DPA Pump Rebuild Manual.pdf

Hope someone finds this useful.

Raw Dodge · Nov 13, 2009

Thank you for sharing...I had a diesel that had a dirty tank,i put a cheap clear inline filter between the tank,and main fuel filter,it was under no pressure just gravity feed.I changed it about 10x in 2 weeks before it stopped plugging ever few hours...