Final drive ring gear and hub

Deano aus · September 12, 2010, 01:49:42 AM

Hello, new to this forum from Australia. I am rebuilding a hg crawler and are having trouble with the left hand side final drive.
It seems that the hub studs have broken and bent. Do any one know if I can get another hub as this one is so far gone.
Any photos of a final drive (left side 10 studs) would be great!!! Thanks again Deano. Australia Vic.

Deano aus · September 12, 2010, 01:50:03 AM

Hello, new to this forum from Australia. I am rebuilding a hg crawler and are having trouble with the left hand side final drive.
It seems that the hub studs have broken and bent. Do any one know if I can get another hub as this one is so far gone.
Any photos of a final drive (left side 10 studs) would be great!!! Thanks again Deano. Australia Vic.

Jethrow · September 12, 2010, 06:35:21 AM

Deano,

This is from the right side of my OC-3.

Jethrow

Deano aus · September 12, 2010, 11:00:24 PM

Hi Jethrow, thanks for your photo,Do you know where in the usa I can get one of these hubs?? I notice that mine is different where the pinion is. Mine has only one bearing on the inside and a sir clip on the other?? Does anyone know why?? Thanks again Deano.

John Schwiebert · September 13, 2010, 01:37:43 AM

There were two styles of those. Do you have a serial number or a picture?

Deano aus · September 16, 2010, 11:25:02 AM

Hi John, I dont have the serial number on me but I emailed zimmerman and he said that he did not know why it had 10 studs as the pinion gear has 17 teethand the ring gear has 70 teeth. He only has 15 and 72 teeth. I think it must be an early model??? Do you know of anyone that would have a ring gear?

? Thanks again Deano

oliverchris · September 20, 2010, 12:00:29 PM

G'day Deano,
Yes, early models had 5 studs per sprocket. See my pic. And ring gear went from 72 teeth (with 15 tooth pinion) to 67 teeth (with 14 tooth pinon) BUT WHEN? Manual is very unclear on both of these points. In fact it doesn't even mention a 5 hole sprocket. I wonder if John S. can dig out some service bulletins for us? Service Bulletins CL-634-A and CL-653 might throw some light on this.
However, manual does suggest that earlier models should be upgraded to the later set-up.
For sprockets, Service Bulletin CL252 is suggested as a MUST READ for anyone with a machine up to serial number 31GA679 (mid 12947).
Also, says that earliest HGs (into early 1941 up to 5GA179) had only one pinion gear bearing instead of two.

I will post a pic of the inside of these finals soon. I will have them up for sale soon. I am presuming it has the 72 teeth drive gear.

oliverchris · September 14, 2012, 10:50:54 PM

Just re-read an old post. I meant from 67 teeth (with 14 tooth pinion) to 72 teeth (with 15 tooth pinion).
Now I am just trying to figure out the similar progression dates for tooth count changes in OC4s. I am sure earlier ones had the same bull and pinions as OC3s. No tooth counts mentioned in any shop manuals or parts manuals.