I changed the fuel filter, filled the housing with fuel and tightened everything down and when I went to start it, it crank a little and fired missing on a couple cylinders, picked them up eventually but then started bleeding fuel and air out a vent tube under the floor boards then started acting like it was running out of fuel. I shut it off before it died, checked the filter housing and it was almost empty so I refilled it and tried it again and had the exact same result. What did I do wrong and why does it continue to bleed air and fuel out the vent under the floor boards?
I failed to add that it was a 1979 Komatsu Dozer. It's new to me and before I used it I thought I'd change the filters.
I believe that it has a float tank that regulates the fuel I have had to pull these and clean them out sounds like what you are talking about. Without the float tank fuel would flow thru the injectors and fill up crankcase
Thanks Dave. I found the float tank and it appears to be working fine. The hose under the floor boards that surged air filled fuel when trying to run was attached to that float tank and a return line from the fuel filter system. I am confused though that there doesn't seem to be a manual lift pump on the fuel system somewhere to help in the bleeding off of the air in the fuel system, even just to help in the filling of the filter canister or even to pressureize the fuel pump before cracking the injectors to relieve the air. There was a knurled knob on the the front drive side of the injection pump that looked like a round barrelled shaped 1" pump in the vertical position that I felt should have been, or at least looked like it could be a lift pump. When I loosened the thumb cap, it did not have anything fastened to it that could create a pumping action or no spring loaded plunger for plunging/pumping fuel. Confused on the lack of manual lift pump.
the lift pump is built into the PT pump the knurled knob is the override for the fuel shut down solenoid turn it in and it will run without power and wont shut off until you screw it out. I normally get it running with knob in and keep ignition off then screw it out till it shuts off get fuel to you filter and then at the feed line at the injection pump and it will crank up you should have a compression release if you want to pull it to help bleed it out
Screwing that knob in will fill the crankcase full of fuel if the engine isn't running. No hand pump on these engines because the tank is mounted higher than the engine.
Thanks for the interest and responding. I will keep you posted on what I find but the sun is out so my work load just doubled (farmer), I may not get at it today or till late, but will keep you updated on my progress.
Did you ever get back to your D65? I have the same machine I am getting the same fuel air vapor out of vent. I’ve put around 10 hrs in trouble shooting but still haven’t gotten it straight. I’m planning on giving it a few more hours tomorrow but probably pulling the injection pump for a rebuild. It doesn’t seem to pull fuel even when eliminating everything else.
What is the proper shut off procedure for the D65-a. I had been using the compression release thinking it was an Air shut-off,
just turn the key off
Nope, wiring is trashed. No alternator/generator hooked up. I just keep the batteries charged up. I'll look for a Fuel shut off silenoid.
then you have to back out the knurled knob till it shuts down screw it back in to start
Thanks