My Tractor Forum banner

1 - 20 of 28 Posts

·
Registered
Joined
·
2,545 Posts
Re: For those who have never seen

Heck, I don't think I've ever seen a 4-lead set! Thanks for posting.
 

·
Gravely bug bit.
Joined
·
8,731 Posts
Discussion Starter #3
Re: For those who have never seen

Heck, I don't think I've ever seen a 4-lead set! Thanks for posting.
They are kind of rare. It is going south to reside in a 1960 L. Now I'll have to stamp the plate so it read LS. An LS with GRWs should make for a good rotary plow unit.
 

·
Registered
Joined
·
2,545 Posts
Re: For those who have never seen

An LS with GRWs should make a good unit for pulling semis :D
 

·
Registered
Joined
·
376 Posts
Re: For those who have never seen

They are kind of rare. It is going south to reside in a 1960 L. Now I'll have to stamp the plate so it read LS. An LS with GRWs should make for a good rotary plow unit.
I ant to try the GRW's on my LS as well. I put them on my LI with rotary plow and it works awesome. Don I have a set of gears that are spposed to be 4 lead. The worm is still attached to the shaft and has the worm bearing cones still attached as well. How can I tell if it is indeed a 4 lead without dissasembling it?
 

·
Premium Member
Joined
·
3,028 Posts
Re: For those who have never seen

From Chip Old,

Jack up the tractor so one tire is off the ground. Make sure the other wheel
remains on the ground, or find another way to prevent it from turning.
Remove the spark plug and (if electric start) the starter chain so the
engine can be turned over by hand. Rotate the crankshaft and count how many crankshaft revolutions it takes to rotate the wheel 1/4 turn.

L or C
8-lead worm
1/4 wheel rotation requires 6 crankshaft rotations.

LI or CI
6-lead worm
1/4 wheel rotation requires 9 crankshaft rotations.

LS or CS
4-lead worm
1/4 wheel rotation requires 12 crankshaft rotations.
 

·
Gravely Fan
Joined
·
881 Posts
Re: For those who have never seen

the comparison of a 4-lead worm and worm gear and a 6-lead set, behold.
Now what other tractor (in the scale of a Gravely not a large JD) had gears like that? Aren't those gears a thing of beauty? - Kris :rauch10:
 

·
Gravely bug bit.
Joined
·
8,731 Posts
Discussion Starter #9
Re: For those who have never seen

Now what other tractor (in the scale of a Gravely not a large JD) had gears like that? Aren't those gears a thing of beauty? - Kris :rauch10:
Working with brass items that big is always fun. For those who've never seen Gravely gears, they scare them when they see they're worm gears and the sheer size of them. As for that 4-lead set, there is nearly no wear on the worm gear. Which is shocking.
 

·
I Love All Color Tractors
Joined
·
22,321 Posts

·
Registered
Joined
·
2,545 Posts
Re: For those who have never seen

From Chip Old,

Jack up the tractor so one tire is off the ground. Make sure the other wheel
remains on the ground, or find another way to prevent it from turning.
Remove the spark plug and (if electric start) the starter chain so the
engine can be turned over by hand. Rotate the crankshaft and count how many crankshaft revolutions it takes to rotate the wheel 1/4 turn.

L or C
8-lead worm
1/4 wheel rotation requires 6 crankshaft rotations.

LI or CI
6-lead worm
1/4 wheel rotation requires 9 crankshaft rotations.

LS or CS
4-lead worm
1/4 wheel rotation requires 12 crankshaft rotations.
Roger, that's in high gear, correct?
 

·
Gravely bug bit.
Joined
·
8,731 Posts
Discussion Starter #12
Re: For those who have never seen

I ant to try the GRW's on my LS as well. I put them on my LI with rotary plow and it works awesome. Don I have a set of gears that are spposed to be 4 lead. The worm is still attached to the shaft and has the worm bearing cones still attached as well. How can I tell if it is indeed a 4 lead without dissasembling it?
Is it in or out of the tractor? You can do as Roger said on an assembled tractor or you can mark a tooth on the worm, rotate the shaft, and count the leads till you get back to the original. The counts will be either 4, 6, or 8 depending. Do not count lenghtwise as you'll come up with the same on 4 and 6 leads.
 

·
Premium Member
Joined
·
3,028 Posts
"Roger, that's in high gear, correct?"

That info was not in the orginal post, but I would bet that test was conducted in HIGH.

Depending on tire inflation, wear and tread design, the average 480 - 8 tire has a circumference of 50 - 51". With the info below you could do the math.

engine speeds and ground speeds.jpg

Double click the chart to enlarge.

Roger,
 

·
Registered
Joined
·
2,545 Posts
My calculations produced 8.1 crank revs per 1/4 wheel rev for an L in high gear. For an L in low, I obtained 11.2 crank revs per 1/4 wheel rev. The 8.1 is closer to the 6 listed in Roger's post for the L, so I'm going to say that it is in high gear. I think my calculation would be closer to the 6 crank revs per 1/4 wheel rev but Gravely's mile per hour numbers may be slightly off, or the circumference of the tire may be slightly different than the ideal 50". I'm sure there's some deformation that would change the actual forward distance traveled per wheel revolution with rubber tires. Anyway, high gear should be correct for that test.
 

·
Registered
Joined
·
376 Posts
Re: For those who have never seen

Is it in or out of the tractor? You can do as Roger said on an assembled tractor or you can mark a tooth on the worm, rotate the shaft, and count the leads till you get back to the original. The counts will be either 4, 6, or 8 depending. Do not count lenghtwise as you'll come up with the same on 4 and 6 leads.
It is out of the tractor. I take it what you mean by "Do not count lenghtwise " is just rotate the gear and count the teeth that are around the bottom . I marked the gear , rotated it and came up with 4. :thThumbsU Then I remembered I have a gear that came from a LI so I did the same with it and found 6.
 

·
Gravely bug bit.
Joined
·
8,731 Posts
Discussion Starter #19
Don,

Take a picture of a six lead worm sitting on a four lead worm gear.

Roger,
That will have to wait till I get back to Florida. Naw, I'm not that mean. :D First is 4-lead worm on 6-lead worm gear.Second is 6-lead worm on 4-lead worm gear. Third shows lead numbers stamped into worm gear. 4 is at the top of pic, 6 is at 9 o'clock position in pic.
 

Attachments

1 - 20 of 28 Posts
Top