Update - Obviously this issue hasn't been real urgent for me... lol I tried the whole removing the lid to make sure the vent works. No joy. Vent works fine. I blew air back into the tank from the fuel filter. I could hear it bubbling in the tank. That was one day early last week. I also added some Poweer Service Clear Diesel at the time. I tried to run a camera down into the tank to see if I could see anything, but I couldn't see a darn thing. Too much fuel in the tank still to be able to see anything on the bottom. Didn't really have a chance to use it much until yesterday and the problem returned in about 5 min. Thinking back, when i was blowing air into the tank, fuel never did try to run out of the fuel like like it SHOULD have. I finally got it moved over to the driveway where I don't mind spilling a little fuel on the ground now and then. Pulled the fuel line off at the tank. No fuel coming out. Blew air into the drain, and fuel started pouring out. I had the line off at the fuel filter too so I got it hooked up at the tank, then ran around to the filter and hooked that up as well. Fuel bowl STILL didn't want to fill (it was only half full).
I did notice some junk in it so I started to take it off and drain it. As soon as I had it loose enough for the air to drain, fuel started pouring out so I just tightened it back up. At first I thought I had fuel leaking back from the fuel pump and I started cursing myself for not clamping that line off like I would normally do when changing a fuel filter. I soon realized that I had drained noticeably more fuel than what the pump and injectors could hold so what ever the root cause was, it had now gone away. I only ran it about an hour after that, but it had no issues and the bowl was always full. Since the fuel wasn't draining when I had the line off at the tank, OBVIOUSLY there was/is something in there causing a problem. Once fuel was draining though, I would have expected the fuel bowl to fill without having to vent the air out. I would have expected the line on top of the fuel filter to vent the air back into the return line. Am I missing something there?
FWIW, I changed the fuel filter about a month ago. That was the first thing I did to try to address this problem. The problem has gotten progressively worse sense then (until yesterday). The PO used the machine to maintain his deer lease so it sat for long periods of time. I'm wondering if he didn't use some fuel with Biodiesel in it, and I'm dealing with algae. I have some work to do with it tomorrow. When I'm done, I'm going to go ahead and drain the fuel filter again to get the crud out of the bowl. I'll also pick up some Bio Kleen on the way home tonight and add that to the tank before hand.
