Hello all , first post here but been reading for a while. Wondering if someone has ever had to clean the relief valve on the newer 15001 and above style control valve ? I have one that is getting slow hydraulics and wondered if it would help like on the older style (gresen) type in other threads here. I can't seem to find a much info. on this valve setup , bobcat parts online has a picture of it actually talked about in this old thread http://www.skidsteerforum.com/DesktopDefault.aspx?tabid=54&frmView=ShowPost&PostID=30799&PageIndex=2 The picture parts list calls 2 things relief valves , the adjuster looking one #26 and the one below it #27 . It looks like you get to it from the rear of the machine thru the engine area. Has anyone ever cleaned one on this type of valve ? Which one is it that needs cleaned , I think the top one may just adjust the pressure. Thanks in advance for any help , sorry can't figure out how to post the pic of the valve here on the tread. I will keep trying to post the picture of the valve as I see other people doing it like in the ref. thread above. Thanks again fo any help
743 control valve relief 15001 & above type
- Thread starter sque
- Start date
As you have noticed, there are two. One is there to limit the pressure in the lift circuit alone, it is set higher than the main relief.
From memory, there is nothing special about the internals of the relief, just note where parts go when you take them out for cleaning.
Thanks Tazza
Ok , thanks for the info. , slugish weak hyd. , I have a kit coming for the pump and also replacing the 10" 1.00 sae100r4 suction hose as I think it could be sucking air around conections because the old hose has turned hard over time and the clamps may not be sealing /squeezing well on it anymore. I also ordered a presure plate for the pump because it has an oil-light bushing for the drive shaft end in it that seems like it could be worn. I'm not sure what size it should be but it measures .416" (ID bore) and the shaft end mics .406" so .010" oversize seems like alot to me when dealing with a bore. Concentrisity is good .416" no egg , and still has oil passages in it, so if its worn its wearing even. I dont see alot wrong with the vanes or ring on visual inspection. I'm interested to get the new stuff so I can mic it to see if there's a difference . If the ring is worn it is worn uniformly because I checked it with verneers to spots in relation to the location dowels and it seems pretty symetrical.
I'm not sure if there is another bushing in the housing side of the pump as I just have the front half off. From the drawing it looks like the other end of the drive shaft couples to the hydrastatic and uses its bearing.
The drive is spot on. Its just lift and tilt , nothing leaks , doesn't whine.
Not seeing any clear issues in the pump makes me feel like it may be a valve open or somthing.
Vane pumps wear very well, any wear that happens, the vanes take this up.
The main issue they have is the cam i think they call is, the part that the vanes flick out and run on, these can get bumpy and this will cause pressure issues. I'd pull the main relief out and see if it's broken or has something stuck in it. This should just lower your lifting power, but it still should move fast and not slugish as you mention.... See what the new pump parts look like.
You are rite, behind that shaft starts the hydrostatic pump, no need to get in there if it drives fine.
![Pampers Sensitive Baby Wipes, Clinically Proven, Fragrance Free, Unscented, Water Based, Hypoallergenic, Multi-Use, Hand Wipes 336 Wipes Total (6X Flip-Top Packs) [Packaging May Vary]](https://m.media-amazon.com/images/I/41KLBHu9CAL._SL500_.jpg)
