Hi guys. I was out dozing today with my 48 D2 5U 1011 (new to me in Jan) and the main clutch started slipping under load which it’s never done before. I rolled her into the shop just figured I needed to adjust it up quick but after removing the cover I found the whole case and all components covered in very black dirty oil.  Obviously the cause of the slippage but I’m wondering where it came from? I changed all the fluids in it when I got it and they all still show clean oil on the sticks when pulled so I’m at a loss on its origin. The clutch housing has always been dry up until now so any info on where it is coming from would be appreciated. Thank you , Kael.


 

I think the D4 is similar to the D2 in that there is not really a seal on the main but an oil slinger. See this thread about the same problem on a D4.
If you are not going to be in water, add a small hole with a cotter key in the drain plug to prevent filling the clutch compartment with oil

www.acmoc.org/bb/discussion-d72/24867-d4...ear-main-seal#203031

Unless you have cleaned this compartment in your pre use servicing , the slim may have been there. How much have you operated the dozer? And what was the temperature? Warmer temperatures just made it more fluid. I believe all the operators books tells how to wash the compartment. Get it clean and try it again. Park with it as close to level and check oil levels closely, after operating it several times. Also if you put the nose up hill it tends to weep a bit more around the oil slinger on the crankshaft.

Check to see if your oil has diesel fuel in it. The oil slinger can have trouble working properly if the oil is thinned by diesel and there is too much liquid to handle. I had this problem with my D4. There are numerous threads that discuss the problem of fuel getting into the oil. Just a possibility, something to check.

Bruce

Thank you all for the responses. I will get her cleaned up and take note of my oil levels and run her again and see what I come up with.