Hello Everyone, I just bought my first Cat, a 12, 8T, missed the oil clutch by 390 serial numbers, #15971, to grade the road to my house and my neighbors. My story is like many others which I’ve found out after reading the threads here and watching many videos online.  I saved this old girl from the scrap yard, literally by a day.  I had spoken to the owner about 3 months earlier, found him on Craigslist, had a JD grader that I looked at, no way that it was going to run, way to many parts missing, he comes across projects, picks them up, does a little work and then sells them. He told me if I’m not in a hurry to stop back and see how he’s doing with one of the Cats he had. He has a lot of projects, and I found out later the county thinks he has way too many.  Anyway, gave him some time, and then I decided to stop back by and see how things were going.  In between time the county had told him he needed to get rid of some stuff or he was getting fined. When I pulled up I saw the two other Cat 12’s that he had there, were getting gas axed and loaded on a trailer.  Holy crap Batman! We did some horse trading right then and there, bought her a stay of execution for a week while I devised a plan to get her running and out of there in one piece. I think the Good Lord was watching out for me and said stop by and say hi, one more day and she would have been gone. So I got her running, no not with the pony, that’s why he couldn’t get the machine running, and not enough time.  I got a 24 volt starter from George at Autolec, he was very helpful, he got the starter to me quick, I didn’t have much time. Found good info here on the forum, and she was ready with the factory hole in the bell housing for the starter!  Getting the pony running in the future is something I’ll try to do.  So, with all the fluids checked, new fuel, fuel filters, starter, and the fuel lines bled, she fired right up as advertised!  With just an hour to spare, the truck  showed, we loaded up and got her home.  So now there’s not the emergency to get her moved, safe from the gas axe, I now have time to go through and give her some love, got all the manuals from eBay so I know what I’m doing, well kinda, changed out all the fluids and filters, put new gauges in, they were all broke, new seals in a couple of places to fix some hydraulic leaks, cleaning and lots of greasing.   Here’s where I’m needing some guidance/advice.  I pulled the wheels to get some different rubber, they all were dry rotted, as I was pulling the right rear I noticed the wheel hub was loose. See the photos where I drew a line to see how much it moved, about 1/2 to 3/4 inch. From reading the threads talking about brakes on these machines, the hubs need to be dry fit on to the spindle with 30 tons of pressure, or there’s going to be some damage.  This is where I got a little bit of a pit in my stomach. I got a 24” pipe wrench, I know! It’s all I had out here in the desert and got the nut off, I’ve got a socket on order.  The hub and drum came right off.  I think the hubs were pulled at one time for brakes, looking at how good of shape the pads are in, and the hub didn’t get put back on the right way.  Just a guess, not sure about the other, it seems tight, but that’s in question.  I’ve got lots of pictures of the inside, the slot on the one side of the spindle looks tight, the key stays in while pushed in from underneath, doesn’t fall out.  But is the key long enough, it seems short, 4 inches?  The slot in the hub doesn’t look so good, can that be fixed? Welded and machined, or is a new used hub the fix? The nut threads all the way on smoothly but it looks like I need to file the end of the spindle where there are a couple of points at the end. The nut didn’t seem tight to the hub, there was a little space, those metal burrs look like it could be holding the nut out.  Is the shaft okay?  Finally, what’s the correct way to get the hub pressed back on, methods / tools, can I do it or do I need to call a field truck with hydraulic equipment. I hope I caught this in time, and no other damage was done.  Other than this, everything has checked out, she’s in good shape!  I want to take care of this machine, give her some new paint as time permits and keep her running for years to come. Thank you in advance, any help will be greatly appreciated.  

Hello Everyone,

I just bought my first Cat, a 12, 8T, missed the oil clutch by 390 serial numbers, #15971, to grade the road to my house and my neighbors. My story is like many others which I’ve found out after reading the threads here and watching many videos online.  I saved this old girl from the scrap yard, literally by a day.  I had spoken to the owner about 3 months earlier, found him on Craigslist, had a JD grader that I looked at, no way that it was going to run, way to many parts missing, he comes across projects, picks them up, does a little work and then sells them. He told me if I’m not in a hurry to stop back and see how he’s doing with one of the Cats he had. He has a lot of projects, and I found out later the county thinks he has way too many.  Anyway, gave him some time, and then I decided to stop back by and see how things were going.  In between time the county had told him he needed to get rid of some stuff or he was getting fined. When I pulled up I saw the two other Cat 12’s that he had there, were getting gas axed and loaded on a trailer.  Holy crap Batman! We did some horse trading right then and there, bought her a stay of execution for a week while I devised a plan to get her running and out of there in one piece. I think the Good Lord was watching out for me and said stop by and say hi, one more day and she would have been gone.

So I got her running, no not with the pony, that’s why he couldn’t get the machine running, and not enough time.  I got a 24 volt starter from George at Autolec, he was very helpful, he got the starter to me quick, I didn’t have much time. Found good info here on the forum, and she was ready with the factory hole in the bell housing for the starter!  Getting the pony running in the future is something I’ll try to do.  So, with all the fluids checked, new fuel, fuel filters, starter, and the fuel lines bled, she fired right up as advertised!  With just an hour to spare, the truck showed, we loaded up and got her home. 

So now there’s not the emergency to get her moved, safe from the gas axe, I now have time to go through and give her some love, got all the manuals from eBay so I know what I’m doing, well kinda, changed out all the fluids and filters, put new gauges in, they were all broke, new seals in a couple of places to fix some hydraulic leaks, cleaning and lots of greasing.  

Here’s where I’m needing some guidance/advice.  I pulled the wheels to get some different rubber, they all were dry rotted, as I was pulling the right rear I noticed the wheel hub was loose. See the photos where I drew a line to see how much it moved, about 1/2 to 3/4 inch. From reading the threads talking about brakes on these machines, the hubs need to be dry fit on to the spindle with 30 tons of pressure, or there’s going to be some damage. This is where I got a little bit of a pit in my stomach. I got a 24” pipe wrench, I know! It’s all I had out here in the desert and got the nut off, I’ve got a socket on order.  The hub and drum came right off.  I think the hubs were pulled at one time for brakes, looking at how good of shape the pads are in, and the hub didn’t get put back on the right way. Just a guess, not sure about the other, it seems tight, but that’s in question. I’ve got lots of pictures of the inside, the slot on the one side of the spindle looks tight, the key stays in while pushed in from underneath, doesn’t fall out.  But is the key long enough, it seems short, 4 inches?  The slot in the hub doesn’t look so good, can that be fixed? Welded and machined, or is a new used hub the fix? The nut threads all the way on smoothly but it looks like I need to file the end of the spindle where there are a couple of points at the end. The nut didn’t seem tight to the hub, there was a little space, those metal burrs look like it could be holding the nut out. Is the shaft okay? Finally, what’s the correct way to get the hub pressed back on, methods / tools, can I do it or do I need to call a field truck with hydraulic equipment. I hope I caught this in time, and no other damage was done.  Other than this, everything has checked out, she’s in good shape!  I want to take care of this machine, give her some new paint as time permits and keep her running for years to come. Thank you in advance, any help will be greatly appreciated. 

Hi, SouthernCat1.
Congratulations and welkum too ther klubb.

As you said, the rest of the machines looks to be in pretty good shape - at least from 10.000 or more miles away.

I'm guessing that the two on the flatbed trailer are headed for a slow boat trip to China.

I think I would be looking for a dismantler with a good hub AND axle assembly 'coz i didn't like the looks of the keyway in the axle either. But that's easy for me to say from way over here when I don't hafta get my hand in my pocket.

If it has been run much with the hub loose on the axle, it might be a problem getting it to stay tight, even with being pressed on and even with a better hub. The slightest scope for movement will bring a press fit undone. Part of the issue is that there is NO differential in that drive on top the fact that all tandem drives scrub on the ground when turning.

You WILL need the hydraulic press equipment to do the job properly. It would be a good idea to make sure the other wheels are fitted correctly at the same time.

The nut is only really there to hold the wheel on IF the press fit fails.

Just my 0.02.

Welcome and best wishes on your new toy. Quite an interesting save. I own 8T15911, same thing, missed the oil clutch; mine only gets used a few hours a year here, but glad to have it for grooming roads and such.
Those keyways need attention for sure. Donor machine or find a good machine shop?
Keep us posted, and of course, photos are always welcome. JM

I want to welcome you to the club also!  From your photographs, it looks like you landed a really clean No.12 grader.
If you don't have a spare hub available, then based upon your photographs, I would remove all the burrs on the shaft and the hub, install a new key, and press everything back together as is.  Definitely, you will have to have the hub hydraulically pressed on the shaft, and if you don't have such equipment then pay someone to do it for you.  I think that with the proper press fit of the hub and the amount of "meat" still on the keyways the hub should be secure... if not then you are at the same place that you are presently.