I've been trying to start my sled to get it running for the season which is just starting here. It's a 2009 Expedition TUV WT with 600SDI HO engine. At the end of last season I siphoned the gas from the tank and left it empty for the summer. In the fall I attempted to run the sled to get it ready for winter. I put about 5L of gas treated with Seafoam into the tank and tried turning it over. The engine would not start.
I then left the sled sit until a few weeks ago when I tried again. I took battery out and fully charged it to make sure I was getting the full cranking amps. The engine started after a few tries but would not idle. After a few attempts, the engine idled for a few minutes but the idle seemed to need to build a bit. After restarting a few times it would idle shorter and shorter until it would not idle at all. I even tried putting a little gas directly into the cylinders, but this would only turn the engine over for one or two cycles.
I then left the machine again for another week and for my next attempt to start I installed clean new spark plugs and checked the spark against the engine block. A good solid spark. As temperatures are constantly below zero here now, I put a tent over the sled engine and heated it up for a few hours. I also siphoned the treated fuel out of the tank and filled the tank full of new fuel, with some seafoam added. Engine turned over when I tried to start but it could not keep it going. Again, every time I started it would turn over for shorter time until it would not start at all. it would turn over with a little gas put directly into the cylinders, but would not start. I swapped the relays to check them.
I suspect that I may have a dirty fuel line or dirty filter, but don't know where the filter is to check. Another thing I suspect is that i may have got some moisture in my fuel line after leaving the tank empty all summer.
Any ideas or pointers would be much appreciated.