Is this spool bad?

[BeezFun]

This valve leaks slowly when connected to a cylinder, it's a valve I bought from Surplus Center but didn't get around to using for 8 years. There are visible lines on the finished surface of the spool running in the axial direction, but I can't feel any of them with my finger nail, so I don't know if these are normal or if they indicate the source of the slow leak. I tried to get a photo but it's hard because the reflection washes things out. Each finished surface on the spool has some of these marks, the ones most visible in the photos are on the lowest finished surface in the photo.

 

[Groo]

Normally I see small grooves around the circumference to help the valve move smoothly, I also expect a few tapered slots to meter the flow a bit as you first move it. My initial reaction when looking at those pics is the spool is much cheaper than the ones I normally see at work.

Remember a chromed surface of the spool is much harder than the cast iron housing the valve runs in. What caused your barely visiable lines might have done more damage to the softer iron than the little scratches you are worried about.

The cheap machining on the spool has me wondering that the tollerances of the valve section might be problematic.

 

[leonz]

Time for some "good" new valves! That linear score mark should not be there.

 

[BeezFun]

Time for some "good" new valves! That linear score mark should not be there.

Where do I buy a good valve? I've seen several people recently talk about what good luck they've had with Surplus center valves. Or are they buying a different brand? These are Prince.

 

[Groo]

Here is a pick off of an ebay listing for a parker v20 spool for a single acting valve. It just looks like they put a bunch more effort into the machining of it.

It is a bit simpler because it is for a single acting cylinder, but you get the idea.

The V20 is a very established valve that has been out there "forever". I don't know enough about hydraulics to say your prince valve is a "bad" valve, but it definitely does look cheaper.

 

[BeezFun]

Here is a pick off of an ebay listing for a parker v20 spool for a single acting valve.

Local hydraulic place carries Parker, I'll see what a replacement for mine costs. Problem is I've got 3 valves and a power beyond section. So this ain't going to be cheap.

 

[oldnslo]

Beezfun
I would check the leakage rate on your valve Before condemning it. To figure leakage you will need to know the cylinder size and accurately measure drift vs time.

If is on the tilt cylinder you will need to know the bore & rod diameter so that you can figure the rod end area.

You might be surprised on how small of a leak allows the cylinder to extend.

 

[MtnViewRanch]

Where do I buy a good valve? I've seen several people recently talk about what good luck they've had with Surplus center valves. Or are they buying a different brand? These are Prince.

This is what & where I get the units that I sell. I have not had a single issue with this 12GPM stacking valve system. :thumbsup:

 

[BeezFun]

Beezfun
I would check the leakage rate on your valve Before condemning it.

I can figure it out tomorrow, but I know when I have the bush hog on, the tilt cylinder will drop about 1/2" in 2 minutes. I ended up pulling the QDs so I could finish mowing.

 

[BeezFun]

This is what & where I get the units that I sell. I have not had a single issue with this 12GPM stacking valve system. :thumbsup:

thanks, I'll price that out tomorrow.