hydraulic safety valves...suitable replacements?

   Hello, again. Corey in Lincoln, Mo. here. I'm looking at possibly replacing the bulldozing safety valve on my HD7G, and as I know no AC part is available new (at least below the national debt) , I'm wondering if any of you geniuses know of a suitable replacement, maybe cat or JD. I think it's 3/4 pipe mount (correct me if I'm wrong, please) and length is not a factor. I get the symptom of the bucket just folding under if I try to doze with it, and it takes little force to acccomplish this, although it seems to have pretty good power in tipback. I always thought that if the dozing safety valve was leaking, then you would get leakdown on the bucket creeping down in the hold position. Maybe the safety valve spring is sacked or broken, and just shows up bad when you're pushing something? I'm going to try to get some guages on it but I don't yet own a flow meter. Appreciate any advice. I took the side case off the shovel reservoir and remove the suction screen: I'll post a pic tomorrow of all the crap that was in that screen. Mostly some sort of fibrous stuff that was burgundy color and looked like the red stuff you peel off of baloney before you eat it. Lots of dirt and old crap as sediment. I flushed with diesel and then wet vac'd it. All clean now.

 Coke,  OK, but what could be wrong in valve body to cause that much fluid slippage? Are not the outlets hoses to lift and dump blocked off by valve spool in the hold position? Or the bucket spool check valves dirty of sticking. The bucket seems to be real strong while backdragging.   I can buy a valve body here locally, but it's a second or third design. Do you suppose it would fit?

does the bucket drift when it is above the ground? if it does, it is definitely the packing. coke's test will provide you with the info you need to pinpoint the issue. it should not roll under when grading. good luck and I want to see those pics.

Theyre called bucket line relief valves, designed to 'let go' before something breaks from a external load, like bulldozing with the bucket.
Don,t know there pressures but are about 300lb above normal main system relief valve pressure on a 941 cat.
I usually found it was better to bulldoze with the bucket flat; once the bucket half fills with dirt it acts the same and just pushes the dirt, sure it runs around the outside but that happens with a narrow dozer blade too. 4/1 bucket open the clam abit and use it like a carpenters plane, works fantastic, wider the clam=more bite. my 10c worth anyway, cheers M

Dose that circuit have a return to level circuit in it ? If so that could be the area of problem also . 

The only filter on this machine I never checked, until now. Geeeeez....

 Well, I repacked all the rams yesterday. Pretty straightforward except the lift packings were TIGHT! But now, no more creep-down on the boom. I retested the backdragging and bulldozing holds and now I only have roll-over when dozing. That's why I always ended up digging holes instead of scraping dirt. I'm going to attack that dozing safety valve after I test it's yield pressure. I'm getting close to having this machine fully cured.

Still have my AC 615 backhoe attachment I had on my HD4. 14' hoe with 24" bucket, that drops into toolholder which mounts to back of machine . It is 2 stick valve body setup, with stabilizer legs 

Edited by Coke-in-MN - 05 Aug 2013 at 12:45pm

Looking for about $2500 for the hoe , is a 14' dig and present bucket is 24" - pin size to bucket is 1 1/4" - where my AC715 uses 1 1/2" pins.