I just purchased an M6800 with around 400 hours. Fuel system not service since new. Sediment bowl full of gunk. Cleaned & changed spin on filter. Cannot figure out how to bleed system to put fuel back into filters. There is a pump??? on top of the spin on filter but cannot figure out how to make it work. No manual. HELP!!!
M6800 fuel problems
- Thread starter lfirmin
- Start date
If you can put fill up the filter with as much diesel as you can, then spin up the filter will help a lot. You may need to crack lines open to bleed any extra air out of the lines.
The little round top on the filter base, push down hard and it will pump the filters right up. It's a PIA the first time until you figure out how hard you need to push down on it. It doesn't take very many pumps though.
After that if you loosen the bolt where the line goes in the injector pump just a little then bump the starter over. Just barely bump it and as soon as the fuel squirts out tighten the bolt back down and crank it up. More than likely it will fire right up and then start running ruff. If you are ready to start pumping the hand pump as soon as it cranks it will clear up after a few seconds and be ready to run. Hope this helps.
After that if you loosen the bolt where the line goes in the injector pump just a little then bump the starter over. Just barely bump it and as soon as the fuel squirts out tighten the bolt back down and crank it up. More than likely it will fire right up and then start running ruff. If you are ready to start pumping the hand pump as soon as it cranks it will clear up after a few seconds and be ready to run. Hope this helps.
Not trying to start a war but this is a big mistake especially on the newer engines. It's a death sentence on the teir 4 engines. Any fuel poured, pumped or other wise into a filter before it's installed allows unfiltered fuel to go straight to the injector pump and injectors. This not only causes unwanted wear but you stand a change of stopping up the injector tips. The expence to rebuild a fuel system is thru the roof so why purposely bring trouble to yourself. Sometimes it's a real pain to do things the right way but your tractor and your wallet will thank you for it.
Lossen the nut that holds the fuel line to the injector pump, 1/2 to 1 turn and wait for the fuel to start dripping out around the bolt shaft, tighten the nut up and it should fire within a few turns, (this could take several minutes to bleed all the air out).
I don't know about your setup but on my L1500 there is a bleeder on the filter housig just above wher the fuel line comes out to the injector pump, if I loosen that until the filter fills it really speeds things up.
Bottom line, you have to allow the air to escape the lines and filter at least from the tank to the injector pump before it can prime itself.
I have had some diesel engines where I even had to crack open the injector lines at the injectors and crank the engine until fuel started leaking at the injectors.
On my ford backhoe priming the fuel system is such a bite I even went so far as to install an electric fuel pump between the tank and filter, that made priming the system soooooooooooo much easier.
I expect with the newer engines just bleeding the air to the injector pump should be enough.
Best Regards
Paul
I don't know about your setup but on my L1500 there is a bleeder on the filter housig just above wher the fuel line comes out to the injector pump, if I loosen that until the filter fills it really speeds things up.
Bottom line, you have to allow the air to escape the lines and filter at least from the tank to the injector pump before it can prime itself.
I have had some diesel engines where I even had to crack open the injector lines at the injectors and crank the engine until fuel started leaking at the injectors.
On my ford backhoe priming the fuel system is such a bite I even went so far as to install an electric fuel pump between the tank and filter, that made priming the system soooooooooooo much easier.
I expect with the newer engines just bleeding the air to the injector pump should be enough.
Best Regards
Paul
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