Does any one know if the 9F643 Full-Flow to By-Pass change over kit is still available? Also I have the #44 Hydraulic Control 7F5852 arrangement with the 7F3933 Hydraulic power unit, and would like to change over the disposable spun filter element used to a solid style element if any one has information on this. Thanks Joe Van.

The 9F6430 change over kit has not been available for years, maybe decades. As far as I know there is no after market interchange for the #44 by-pass filter but I believe Cat still has the replacement for a ransom. 

Thanks Old Magnet, I sorta figured, it's been running since the '40's with the original filter system and never been rebuilt as far as I know. I've had it since 8/'77 and changed the oil regularly.
Neil, as far as the #44 filter goes, I found the change out in my 11/2004 records and had the # 7F7238 written down with a note I put in that I said ,"steel cartridge for later model D2 5J & 5U". So your right and I need better records, (that I am putting together at this point). LOL Thank you. JV

If you have the early #44 it takes the same sock type filter as the fuel tower. (former string wound)
Part number 2A5886 = Wix 33825.

Thanks Old Magnet, I think I'm all set with the steel case one. In my notes I have 7F7238 written down, so I must have the later set up which I changed the filter in 2004.