Phyrphighter Posted April 12, 2008 Share Posted April 12, 2008 Hello There, I am the new owner of a 1942 Mack 80 LS. I have some work ahead of me but it's running and I was able to drive it 10 miles to get it home. I have beena firefighter for a number of years but I am not sure that I am engaging this pump correctly. (Hale Z-D) A plate in the rig says to pump in fourth gear. I start off with the rig in neutral - push in the clutch and move the lever that is left of the drivers seat. Then I put the trans. in fourth gear and let out the clutch. I then go to the panel on the side of the rig that has a lever with "Prime" and "Pump" - (I think neutral too) When I move the lever to "Prime" The primer pump runs and sounds a lot like those of all the rigs I have worked on. Then I attempt to move the lever to "Pump" as I get to pump The clutch pedal in the cab goes to the floor (I believe pulled by a vacuum cylinder under the rig) . The pump does not seem to turn with the clutch to the floor. A few times I increased the RPM's using the gas pedal. I believe this created a drop in vacuum allowing the clutch pedal to come out. Each time I have done this there is an enormous amount of grinding and squealing of gears but I don't think the pump is turning. Am I not doing this correctly - or is something hanging up or not engaging correctly in the systemThanks for any help you can offerBarry Lasky Quote Link to comment Share on other sites More sharing options...
twostickmutt Posted April 13, 2008 Share Posted April 13, 2008 Hello There, I am the new owner of a 1942 Mack 80 LS. I have some work ahead of me but it's running and I was able to drive it 10 miles to get it home. I have beena firefighter for a number of years but I am not sure that I am engaging this pump correctly. (Hale Z-D) A plate in the rig says to pump in fourth gear. I start off with the rig in neutral - push in the clutch and move the lever that is left of the drivers seat. Then I put the trans. in fourth gear and let out the clutch. I then go to the panel on the side of the rig that has a lever with "Prime" and "Pump" - (I think neutral too) When I move the lever to "Prime" The primer pump runs and sounds a lot like those of all the rigs I have worked on. Then I attempt to move the lever to "Pump" as I get to pump The clutch pedal in the cab goes to the floor (I believe pulled by a vacuum cylinder under the rig) . The pump does not seem to turn with the clutch to the floor. A few times I increased the RPM's using the gas pedal. I believe this created a drop in vacuum allowing the clutch pedal to come out. Each time I have done this there is an enormous amount of grinding and squealing of gears but I don't think the pump is turning. Am I not doing this correctly - or is something hanging up or not engaging correctly in the systemThanks for any help you can offerBarry Lasky[/qthe clutch has to come back out for the pump to turn after coming out of "prime" gear. a way to see if the pump will turn is to shut the truck off, put it in pump gear, start the truck with the clutch in and let it out slowly while engine running. if it turns dont run it long with a dry pump as water lubricates the pump packing. if it does'nt turn and still grinds it may be just a linkage adjustment. make sure there is oil in the pump transfer case. you can pm me if you want. j.j. Quote and remember "PREFORMANCE COUNTS" Link to comment Share on other sites More sharing options...
Charlie Hatfield Posted April 14, 2008 Share Posted April 14, 2008 Good looking truck! I have a complete manual at home with pumping instructions. I can make a copy and send or e-mail to you. I have never pumped mine Quote Link to comment Share on other sites More sharing options...
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