Prater 75 #1 Posted January 16, 2012 I picked up the D180, its pump was just rebuilt but the company that did the work filled it with transmission fluid. It is also sucking air somewhere with a slight leak on the rear manifold. I plan to drain the system and add 10w30 back in. Should i pull all the lines and hoses, or can i open the check valve and drain the system that way and just pull the hydraulic cylinders and drain them seperate? Also wonderind if the manifold from pump to motor could be replaced with hoses if i made two adapter plates to bolt back on its place. Any help is greatly appreciated. Share this post Link to post Share on other sites
pfrederi 17,881 #2 Posted January 16, 2012 What fluid is in the unit now? Have you run it with a mix? It takes a fair amount of effort to completely drain and flush the system. Even after your best efforts of draining you will probably have to refill it twice (and change filters) to completely get rid of old fluid. The leak is it in the steel lines where they attach to the manifold plate or is it between the manifold and the motor housing? If it is the steel lines the manifolds show up on ebay frequently. If between the manifold and the motor probably O rings or the backer rings have not been installed correctly. They can slip during installation, a little grease holds them in position during assembly. Was the special sealing washer replaced? (I think that it would cause a fluid leak rather than a suction problem but I am not sure) Using hoses might work but would be rather expensive to fabricate. Also the long steel lines help with heat dissipation, rubber hoses would not do well at that. Share this post Link to post Share on other sites
wheeledhorseman 574 #3 Posted January 20, 2012 When I got my C-120 auto, the Sundstrand transmission had been filled with ATF of some sort - red in colour and very 'thin' when rubbed between finger and thumb. You just can't get it all out in one go though I've since discovered with my D-200 that if you remove the accleration valves in the hydro motor you can pretty much empty the motor. (needs to be done in a clean environment) Anyway, I drained out all I could, changed the filter, filled with oil and used the tractor for 10 hours or so. Drained again and examined the oil which had a very slight pink tinge from the residual ATF. It felt oily and not noticeably 'thin' so I replaced with fresh oil but didn't change the filter (rightly or wrongly) on the basis that the residual amount of ATF after the second change would be very tiny indeed and here in the UK OEM filters are a pricey item. The transmission has been good as gold and much quieter with oil when under load. I'm intending to change the oil again sooner than recommended after perhaps 50 hours. Just thought I'd mention this as I went through an what do I do now moment but it seems to have worked out ok. Andy Share this post Link to post Share on other sites
Prater 75 #4 Posted January 21, 2012 Thanks, i appreciate the replies. I will start draining the system this weekend. I used it to move some three point items around in the yard today. It seems to have a lot more power in reverse than in forward, hopefully the oil change will help. Share this post Link to post Share on other sites
