Update on Hydraulic noise on 686

This past Sunday I removed the power steering pump from the left side of tractor to see what kind was in there. I have the Cessna 17 gpm. I looked at the web site for CaseIH to get the part no.'s for the repair kit plus gaskets for the mounting flange and gasket for the belly plate. I had to remove the belly plate because the recessed plug was froze. When I removed the pump with the suction tube attached I found that the O-ring in the pump housing was really worn. I mean the suction tube was a sloppy fit. After getting all the part no.'s from the Case web site I made me a list and called the IH dealer Monday A.M. and ordered all the parts. $176.00. Wednesday afternoon I took the pump apart and installed all the new parts from the kit. I proceeded to install the pump back on the mounting flange when I notice there was 2 O-rings that went between the flange and pump housing where the fluid flows to the power steering and back to the power lift. Thursday am I called NAPA with the correct size for the o-rings and luck would have it they both sizes. I installed the new o-rings and mounted the flange plate and went out to the barn to install everything. Needless to say it always to longer to install that take apart. I finished about noon back to the house and fixed me a bite to eat. (wife's working to pay for toys). Went back to the barn after lunch and filled the trans with fluid and started the tractor and I heard just a slight suction sound when it first started and all was quiet after that. I let the tractor run for about 5 minutes and worked the steering and the 3 pt. and aux lift handles to work the air from system. Checked for leaks and then drove the tractor around for a while and it sure is a lot quieter. I don't hear anything from the power steering pump and everything seems to work really well. I stopped the tractor and checked the fluid level and added another 1-1/2 gal. fluid to bring up to the full mark. I think for the most part the suction tube and the o-rings at the mounting flange was 2 of the critical parts that needed to be replaced. I'll keep all posted to let you know how things work out. Many thanks to all that had suggestions to help fix the problem. James

The piggyback pump supplies the 3pt. The fix that I have found for getting the captive air out of the hydraulic system is to take the return line that goes into the suction tube apart and cap the end that goes to the suction tube and leave the other end open. This will let the air that is captive in the system return to reservoir and not be feed in the suction line. I recommend that you put at least 2-1/2 gallons extra oil in.

Jim J
Thanks for the reply. I'm completely new to the 686. Only had this tractor about a month and I'm trying to learn all I can. I purchased a I&T manual and it tells about removing the power steering pump. If it has draft control there will be a 7 gal pump attached to ps 12 gal pump. When I removed the ps pump no 7 gal pump. I rebuilt the 12 gal and reinstalled and filled with fluid. I run the tractor for a while - stopped - checked fluid - added enough to bring it up to the full mark. This morning I checked the fluid level and it was about an inch above fall. I think that will be about 2 gal over full. Now if everything works well I'll leave it that way. I don't know enough to be plugging the return hoses. I'll have to study that a little. James