First time post, need help with what seems to be a unique situation...
I have a gas 574 with a DuAl 320 loader installed.
It's my understanding that it was purchased new, with loader, by the previous owner, around 1972. The previous owner has passed away. The dealership that sold the tractor is no longer in business.
My problem is with the *additional* hydraulic filter on this tractor. I am only guessing that this filter was installed as an option to provide additional flow capacity for the hydraulic pump as the loader is a heavy duty unit. The 'regular' filter, the one with a can and long bolt, are in the normal position on the left side. There is another filter on the right side. I stumbled across the fact that this was a filter while browsing through the online CIH parts catalog. You can see the parts listing here:
Case IH Online Parts
See photos 1 and 2 of the assembly on the tractor. It's apparently a suction filter, taking oil right into the hydraulic pump. It's located under the right foot plate, where you would place your foot when not using the brake pedals.
I purchased both of the filter kits from my local dealer, drained the oil, installed the left side 'regular' filter, then started to install the additional filter. See from the photos and the parts diagram - there is a two-piece housing for the filter. The removable portion, which is toward the front, is secured to the rest of the housing with a stamped inverted v shaped metal ring clamp. That clamp pulls flanges, one on each part of the housing, together. The flanges form an inverted V, if they were touching eachother. Between the flanges is an o-ring that is trapped between them and seals the housing as the clamp pulls them together. There is a bypass valve that fits into the open end of the filter, held in by the removable cover when it's in place.
There are also three depressions, equally spaced, into the removable portion of the housing. I don't know what their function is, other than to center the filter in the housing during assembly. Those are part of what I'm dealing with. The replacement filter diameter is larger that the diameter limit imposed by those three depressions. As you can see in Photo 3, the filter I removed from the housing has deflections / dents around the media at one end, in order to allow the filter to fit. The filter I removed is identical to the new one supplied by my dealer - same part number and same diameter - too large. The replacement filter doesn't have dents in it.
I went back to my local dealer, and talked with a person in parts as well as the service manager. Neither of them had seen this hydraulic filter before, and didn't know that it was installed on a 574 or similar tractor. I asked them if they had any procedure for 'denting' the outside of the filter to fit, or another part number for a filter that would fit without needing to be 'modified'. They did not.
So I went back to my shop, gently pressed the new filter into the removable housing to give me some idea as to where to make the dents, pulled it out, and worked on making three dents in the filter as best I could and re-assembled, filled the unit with 9 gallons of oil. For a few minutes, I was very pleased, then I could tell I was getting air into the system. The additional filter housing was leaking.
Now I have yet to stop the leaking. Oil is leaking out and I can tell I'm pulling air in when the tractor is running. The clamp won't seat well all the way around the housing. It's got one bolt at one side, as you can see. Opposite the bolt is stamped metal - there's no hinge, etc. there. The housing and clamp are not available from CIH as replacement parts, only the filter kit, which includes the filter and replacemnt o-ring.
I believe the unit may have been damaged due to brush, snow, or something else, as the removable cover only fits onto the housing at a certain arrangement, leading me to think that one or both are out of round. I have photos of the whole thing before I started disassembly and am working toward getting the clamp, cover, and housing aligned exactly as they were to see if that yields a leak-tight result.
I'm about ready to remove the footplate (below the brake pedals) above the unit for better access, so I can see how the clamp is seating around the flanges, but have to trace out where an apparent return spring goes. I'll need to remove it to get the footplate off and want to be sure I know what it does before I touch it. Also about ready to purchase the CIH service manuals for the tractor. I like the unit, it's been reliable, and winter is approaching!
I can't help but wonder if the filter housing design changed during the production life of the 574 and a newer housing would accept the replacement filter better.
Questions for the forum:
1) Has anyone run into this and discovered a different filter that fits into the housing without 'modification'?
2) Has anyone had success replacing the entire filter with another housing / element that works? I'm guessing that since this is a suction side filter the flow capacity of the replacement filter would be critical to success.
3) Any suggestions on tractor salvage outlets where I may find a replacement housing and clamp?
4) Other ideas very welcome