Yoder 640 Wheel up Grade.
Used a floor jack inserted from the hopper end, to raise the end with the castor wheels.
Only removed one leg at a time. Must maintain support
Take the leg to work bench to work on.
The top 4 bolts are 5/16 inch, with a 3/8 nut inside.
Might need a wrench to get loose.
The lower 8 are 1/4" hex head screws.
Caster is threaded into bottom of leg, remove with slip joint pliers
caster is not threaded into leg very tight, once loosened will thread out.
Use a taper drill to enlarge the hole for the caster shank, to the fit the
new caster shank about 5/8 inch
Original threaded hole about 1/2 inch
Enlarged hole about 5/8 inch
Add three washers to the caster stud.
Insert caster stud in leg add another washer and the nut.
I used a nylon self locking nut. The nuts are 16mm. don't panic
if you don't have a 16mm wrench and socket.
15/16 inch is the same size 7/8 inch will work too just a little bit loose fitting on the nut.
The end of the caster stud, inside the swivel is
16mm, use an opened end wrench there and a socket inside the leg
Reinstall the leg. and repeat for the other side .
Finished with the casters.
Remember, Only remove one leg at a time to maintain support
Now for the 16" Wheels.
Purchase a 3 ft length of 1/2 inch rod at a Big Box store,
and two 1/2 inch fender washers.
Jack up the pellet hopper end of the Yoder.
Remove the pins holding the original axels in place remove the wheels and axels.
On one end of the 1/2" rod. Drill a 1/8th inch hole 1/2" in from the end of the rod.
Insert one of the axel pins in the hole, slide on a fender washer the wheel and two washers that were removed from
The original wheel. insert the new axel in one side slide it across to the other side, insert in that axel hole.
On my Yoder there is a slight misalignment between the two sides, Use a hammer to
tap the axel in all the way. Install the two washers, the wheel and the other fender washer.
Using a center pinch, mark the axel as close as possible on the out side of the washer. Drill the second hole, insert the pin. Trim the extra length of the rod.
Using the two washers between the wheel and the leg there should be about 1/4 inch clearance.