Looking at a Cat 12E, stuff to check?

[Clawed Backster]

Going to go look at this machine in a few days, and I want to know what some of the things are that I should be checking on that particular model. Serial #99E10476. Direct electric start, non turbo. Would be for occasional use to maintain my driveway.
Thanks in advance.

 

[Welder Dave]

See how worn the moldboard is where the cutting edges bolt on, especially in the center. Also look at the tires, they are expensive to replace. Other's will have better recommendations on what to check on this particular model of grader.

 

[Clawed Backster]

Thanks, Dave.
I went and looked at it this morning. It hadn't been started in a couple of months, but even though it was right at freezing this morning, it instantly fired up and seemed to run great. I tested all of the controls, and drove it forward and back a little. 5 of the tires are fairly decent, and 1 is bald, but they all seem to hold air. The oil looks great (though significantly over full), and the coolant is clean and green.
I know that it hasn't moved for a long time because I drive by it every day. Even so, there were only a couple of drops of oil under it. As for the cutting edge, it is brand new, though I didn't inspect the attachment point. Overall, the machine seems to be in good mechanical condition.
The dude wants $7,000 for it.
It is bigger than I need, but small graders go for a fortune around here.

 

[Welder Dave]

The moldboard bolt holes are where you need to check for wear. Cutting are fairly cheap actually. Under $200cad. for a 3/4" x 8" x 8' long.

 

[OzDozer]

Serious levels of wear in steering linkages and couplings, and the blade linkages, is usually common in older 12E graders.
This takes a lot of $$'s to fix, as the linkage components are either expensive to replace, or need to be built up and machined down to correct dimensions to take out the wear.

The lift arms for the moldboard have shims under the caps, which can be removed to take out excessive slop. However, many older graders have no shims left due to wear levels.

Check all the universal joints and the gearboxes in the blade control mechanisms, the U-joints wear out and often the bushings in the gearboxes are sloppy.
This allows oil leakage which then shortens the life of the gearboxes, especially when no-one checks the oil levels regularly.

And make sure there's a proper shear pin at the bottom of the vertical driveshaft to the controls box (this is at floor level, there's an access plate there).
If someone has replaced the proper shear pin with a bolt, you'll be looking at serious control box problems when the blade drive mechanism becomes overloaded.

 

[Clawed Backster]

I was a bit concerned about the oil level being over full by what I'd estimate to be a couple of gallons, but later I remembered that some machines are supposed to be running when checking the oil. It probably says on the dipstick, but I didn't think to read it at the time.
Any of you guys know offhand if that is the case?

 

[OzDozer]

Yes, with these old Cat engines, you read the oil level with the engine idling and oil warm. The 12E operation and maintenance manual is your friend.

 

[.RC.]

All I know is make sure the brakes do not work. If they do work there might be a problem as I have never seen a 12E with working brakes.

 

[Clawed Backster]

Yes, with these old Cat engines, you read the oil level with the engine idling and oil warm. The 12E operation and maintenance manual is your friend.

Yeah, if I end up buying it, I will definitely get ahold of the manuals.
And, thanks for the info!