Rockrunner

Worked on it a little the weekend got the #5 delivery valve out of the injector pump it is stuck and looks rusted in side send it off to get replaced then will move onto fuel pump

Where do I attach the fuel pressure gauge and where will I find the spring and ball it doesn't look like it comes apart.

I have return pressure to tank. I pressure washed it today and I am working on it this weekend. My dad says it is the governor but I think it is the fuel pump, but because I have fuel return to tank he says governor. I guess we will find out this weekend

I have two filters on driver side long and short the fuel come from tank into short ( I guess primary) then to the side of injection pump i guess transfer pump, (which is where your tach is installed ) then out back to the other filter then back to injection pump so I should take line off after transfer pump that goes back to second filter? Sound like a good idea if the transfer is not pumping fuel than that's my problem.

Not sure why they are upside down

My injection pump does not look like that it is not that clean yet here is a pic of mine

Just got in from checking it out this is what we did Undo main hose from tank at filter blew into tank lots of bubbles, then pressurized tank, fuel came out hose tighten hose un did filter fuel came out filter, tried to start fuel out return line at tank. Made sure everything was Tightened up. Had to either to start. Runs. Now it will not idle unless you use the throttle cable, and then the idle is rough, will not start with out either does not seem to be responsive with fuel peddle, on top of injection pump is the lines all lines loosed showed fuel and made engine idle rougher except one the 2 nd from back. Now going to try and figure out how to get that thing out and what is it called. Any more suggestion would be appreciated. No fuel prime pump at injection pump. Bummers

Is there a transfer pump or fuel pump before the injection pump?

Ok I will try these things this weekend the injection pump is on pass side the shut off valve is in. Even released the set screw and made sure the lever was fully open. The truck has a pneumatic blower on it and was running at 800 rpm when it started losing power. Drove it home and now it won't start changed both filters the fuel smells like turpentine or thinner I have owned the truck 2 years and not used it much except has a back up to my other blower truck maybe 5 times always started quick and ran good this was sudden. We had just put 20 gallons of diesel in it the day before. I primed the filters try to start then when I take the short filter off it is half empty. So we will try the clean container first I guess. Thanks

Sorry it is a 1990 model Mack .

I have a 92 Mack with Mack 300 hp engine it will run on either primed fuel filters but it won't pick up fuel new to Mack where is he fuel pump?