1910 EMF Ring and Pinion Backlash

[redbaron1930]

I am in the process of setting up the thrust washers and ring and pinion gears on the 1910 EMF. While there is some adjustment on the pinion gear (bearing assembly is on a threaded nut), I would like to get the spacing close with the right thickness axle thrust washers. My initial thought is to shoot for around .015" backlash. Does anyone have a feel for what the range should be on a new set of gears? BTW these are straight cut bevel gears.

 

  Thanks

           Andy

[mikewest]

1 hour ago, redbaron1930 said:

I am in the process of setting up the thrust washers and ring and pinion gears on the 1910 EMF. While there is some adjustment on the pinion gear (bearing assembly is on a threaded nut), I would like to get the spacing close with the right thickness axle thrust washers. My initial thought is to shoot for around .015" backlash. Does anyone have a feel for what the range should be on a new set of gears? BTW these are straight cut bevel gears.

 

  Thanks

           Andy

Andy, You need to get some white lead compond(use can use other things as well)  and pattern the  gears. Its quite easy.  Look on line and see what a correct o pattern looks like when the pinion is adjusted  correct , use a bar or some wood to load pressure on the crown gear and then rotate the pinion. The pattern wants to be not too deep in the crown gear or not to far out on the toe of the gear. Ive used plumbers pipe dope for black iron pipe seal before It works ok just to give you a image of how the gears are meshing. Make sure you clean the dope out of the gears  . Good luck

[mikewest]

Andy , I just Googled  "How to pattern gears in a differential"  Check it out ! 

[cudaman]

IMO 0.007 to 0.010 is a good ballpark to start with, then look at the pattern to confirm.  Just as important is keeping the backlash in the 0.007 to 0.010 range as you rotate the ring gear a full 360 degrees.  If there is too much variation, check the back of the ring gear and the mating flange on the differential for burrs or other high spots that keep the ring gear from fully seating.  You may have things apart multiple times to get it right.  Don't loctite or safety wire the ring gear bolts until you have the pattern and backlash set to your satisfaction.

[mikewest]

7 minutes ago, cudaman said:

IMO 0.007 to 0.010 is a good ballpark to start with, then look at the pattern to confirm.  Just as important is keeping the backlash in the 0.007 to 0.010 range as you rotate the ring gear a full 360 degrees.  If there is too much variation, check the back of the ring gear and the mating flange on the differential for burrs or other high spots that keep the ring gear from fully seating.  You may have things apart multiple times to get it right.  Don't loctite or safety wire the ring gear bolts until you have the pattern and backlash set to your satisfaction.

Good information!

[redbaron1930]

Cudaman & Mikewest;

          Thanks for the tips, I checked things again last night. I get about .005-.006" variation in the backlash, so I took the ring gear and carrier apart again to check and clean the surfaces but it really didn't change anything. I'm pretty happy with the gear pattern. Right now I'm running .010-.015 backlash which i think I will go with.

  I'm not sure if you are familiar with the EMF trans axle setup but it's hard to get a good reading, first of all the pinion gear setup is a bit unstable as it is a single tapered bearing held into the cone by a brass thrust washer which will always have some play ( thrust washer cant be so tight as to prevent the pinion gear from seating on its taper). My goal at this point is to also get the axle thrust washers sized properly ( which also affects backlash.)  Right now i'm checking with just  the left housing attached to the trans axle and a ground shaft going through the bearings and the carrier. I wonder what they did at the factory as there is no way to check this when it is assembled with the actual axles?