Posted by Bill Wincapaw from 12.94.23.8 (8.ft-lauderdale-08rh16rt.fl.dial-access.att.net) on Monday, April 01, 2002 at 5:03PM :
In Reply to: Setting Backlash on PTO posted by Dave Speed from 216.31.2.153 (cnm-dial-153.zianet.com) on Sunday, March 31, 2002 at 10:59PM :
Dave
Your suppose to use a dial indicator to set the backlash between the mating/meshing of the tranny counter gear and the pto idler gear. I did not use a dial indicator on any of the 3 pto's that I have installed in the past ( 2 fuel trucks and one M-37) and have never had a problem doing it the way that I was told to do it ( by the owner of my local driveline shop ). Start with the thickest gasket in your pto gasket set, bolt up the pto (leave the pto drive shaft off), pull the pto cover on the other side of the tranny, reach in and grab hold of the counter gear with one hand and hold the pto driveshaft with the other. Rock the counter gear back & forth ( Make sure tranny is in neutral), you should "FEEL" a slight clicking between the two gears, if not add another gasket ( rebolt down the pto) and rock the counter gear again. Do this until you "Feel" it click. If you have to much backlash remove a gasket. You only need a little clearance ( backlash) between the two gears. The np-420 on my M-37 called for a minimum .001 backlash setting, so as long as you can just feel it clicking ( Have I said that enough?) it should be fine. If anything its better to have a little extra backlash then to little. After you've gotten it to where it feels good rotate the counter gear one full turn and check it again to make sure. The fuel trucks that I've put pto's on using this method have never had a problem, the most recent of those trucks is my F-800 and I did that install 6 years ago.
Regards
Bill Wincapaw
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