Looking for info on a Cat grader

16068 is a 1955 machine with pony start D318 4-1/2 x 5-1/2 diesel engine like GemDozer says.

The 8T series was made from 1947 to 1957. Yours was made just a few hundred machines before the oil clutch became standard from the information I have. Similar direct electric start machines manufactured at the same time as the end of the 8T's were the 80C series.

The 8T machines were preceeded by the 7T with the D4600, 4 1/4 x 5 1/2, 6 cylinder engines.

The next series of US manufactured #12's was the 70D/71D, still with the D318 and oil clutch. The grader oil clutch shared the engine oil instead of having a separate supply and pump like the U series D6 tractors.

22,410 pounds base machine w/o scarifiers, cab, snow wing and other attachments.
100-115 hp setting on the D318 (change somewhere in 1954/1955) vs about 85 on the tractors of that era.

Should be a very useful machine with plenty of new/used parts available still.

Got any pictures?

Oil cooled/lubricated clutches are perhaps the ultimate clutch design. All automatic transmissions, powershift transmissions and of course oil clutches last a lot longer because of keeping the friction surfaces clean and cool.

On the other hand, a properly maintained and operated dry clutch will normally provide very good service as shown by the number of automobiles and light as well as heavy trucks with manual transmissions on the road today, all of which have dry clutches to my knowledge.

The only things odd about the drivetrain of the grader is there is no differential and in place of drive wheels on the drive axle, there are sprockets and tandem housings fitted with chain drives to the wheels. These components are very reliable and do not present any special concern.

You will likely need an operator's manual more than you will need the serviceman's reference book, though you will certainly want to have one of those as well if it's available. I don't think you will find a cheap one unless you are very lucky on here or ebay etc. The operator's instructions/owner's manual has all the lubrication and maintenance instructions in it that you will need to ensure you don't overlook anything and have a failure as a result. There's a huge number of individual service points on the grader just because of the complexity of the machine. It's 1950's technology (or even 1930's), so it's almost intuitive how it works, but there is a lot of it and a few special things as well.

Other manuals for the machine include a parts book and the serviceman's reference book for the D318 engine itself. A little later machines had one serviceman's reference for the whole machine including the engine instead of two.

There are lots of reprint manuals for sale of varying quality, and CAT makes high quality reprints available as well through their legendary equipment literature website
http://www.cat.com/cda/layout?m=90800&x=7

Very interesting, is the wet clutch similar to a torque converter in an automotive automatic transmission? or is it more like a motorcycle clutch? is it possible to swap the dry clutch for a wet clutch if the dry clutch has problems?

I will have to find out what manual he has if any, and make sure I can get all of them, the last thing I want to do is wreck something simply because I didn't know how it needed to be maintained/operated.

Gemdozer: Did you say you have the manuals I need? (Not sure if that's what you said at the bottom of your post) If you do I'm interested.

Thanks a lot for all the info!! It's great to find some people with some real knowledge about these machines👍

The oil clutch simply has oil pumped into the spaces between the disks or bands and drums to keep the friction materials cool and clean with no buildup of dust etc. The friction linings are made to stand the oil. Most transmissions and oil clutches have their own oil supply, but CAT made their early oil clutches in graders to share the engine oil supply.

An automatic transmission normally has a torque converter, but it also has oil clutches and brakes (actuated by hydraulic/electric controls and modulated to have smooth shifts). A power shift may or may not have a torque converter, in CAT designs, they usually do, but the same thing, oil clutches to select the gear ratios under the control of the operator, perhaps with some modulating to smooth the shifts.

If you had a parts grader sitting around or could find one, you probably could swap over to the oil clutch. The clutch housing will be different and perhaps transmission input shaft and transmission housing???? as well as engine oil pump inside the oil pan, but unless those parts come very cheap, you will be ahead to just maintain the dry clutch and replace the linings as necessary. Unless it's on it's last legs now, it will likely last a long time if you keep the proper clearance between the throwout bearing and the clutch release fingers.