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sawatzky1
02-06-2013, 02:40 PM
Ok heres todays question. I understand the spacing difference on the 6U against the 7U is 44" vs 60". My question is track pad width. do the narrow gauge all have narrower pads and the wide guage wider?
Another thing is the difference between a dry clutch and an oil filled clutch. wouldnt the oil cause the clutch to slip? And sometimes i see references to a tourqe converter. that sounds like an automatic or power shift.
So those are the questions, educate me.

ccjersey
02-06-2013, 06:15 PM
""Ok heres todays question. I understand the spacing difference on the 6U against the 7U is 44" vs 60". My question is track pad width. do the narrow gauge all have narrower pads and the wide guage wider?"""""

No, you can put on whichever pads you want as long as you have clearance. There are even pads that have the holes drilled offset so even wider pads can be used for better floatation in special situations. You do realize the 44 and the 60 is the center of the sprocket to the center of the other sprocket?

""""Another thing is the difference between a dry clutch and an oil filled clutch. wouldnt the oil cause the clutch to slip? """"

The friction material in the oil clutch is designed to work with the oil and the circulating oil keeps it clean and cool so it generally last several times as long as a dry clutch.

"""""And sometimes i see references to a tourqe converter. that sounds like an automatic or power shift."""""

Later series tractors were available as torque converter ahead of a power shift transmission or direct drive, but now, I don't think any direct drive tractors are available in any sizes.

Inter674
02-06-2013, 08:14 PM
track pad choices were available when new - so some of what you see on any particular machine relates to standard versus customer choices, and then again 'standard' also varied depending on what Cat decided to supply at the time.

Over time many D2s and D4s have had track pads replaced - often with wider pads because of lower ground pressure and also because wider ones look more sexy. My D2 has narrow 12" pads and whilst I really like the look of wider 14 or 16" ones I will leave it alone because wider pads I think put more strain on the running gear and if they are too wide, they interfere with the lifting ram frames etc.

sawatzky1
02-06-2013, 10:12 PM
Was there a year or model when the clutch went from dry to oil? I'mthinking particular of the D-4.

Inter674
02-07-2013, 04:20 AM
It is referred to in the 1957 7U serviceman's book at the back, so presumably it was an option in later serial number tractors. I do know that some owners filled the dry clutch housing with oil to gain longer life and reduce clutch sharpness. My 1958 D4 7U/30A has a sealed bellhousing and the oil clutch was available for it. However, an earlier D4 7U I have - possibly built around 1953 does not have a sealed bellhousing.

I'm guessing it was an option in 1957.

sawatzky1
02-07-2013, 11:59 AM
Thanks for answering my questions. From what i remember and from the pictures I have I would say Dad's D-4 was a 7U. i have never found anything papaerwork to see what the serial number was but i think the year model was late 40's.
How would a base model tractor come equiped and what kind of options would a unit that was mostly for farming come with? Is there a difference between an Ag tractor and an Industrial model? Dad's was a pony start with a hydrulic pump on the front with a guard. I think the blade was caterpillar. With the blade removed for farming he used the hydrulics on some equipment but most of his stuff was a rope trip.