Backhoe I want to dump this in a ditch and start shooting it until it becomes fun LW-7

[johneic]

I switched hoses/valves and the boom lifted just fine. The linkages/gimbals look just line, the plunger/piston does not depress down (which is up boom) (piston Lifts just fine which is down boom)

So I understand I have to remove the linkages/gimbal?

Then I remove the allen screws, mine only has two allen screws, not four, am I missing something?

Once this cover is off, what do I do? I know I will be looking for something like a piece of seal that is in the way of the piston. I just want to know if there are specific steps that need to be followed (Cleanliness of course) It would be nice to know if there is a whachyamacallit orifice I should not have touched.

 

[RonMar]

No, nothing real fancy to deal with. The top cap if I recall correctly only really holds an O ring seal in place. On the bottom of the valve block is another cover cap held in place with allen head screws. This cap covers the centering spring assembly(2 springs with a washer inbetween) . The cap pushes up on one spring(pushes up on spool), above that is a washer attached to the end of the spool and there is another spring sandwiched between the washer and valve body(pushes down on spool) There will also be another Oring in there someplace I think. IF the spool won't go down you may have to take that washer off the bottom of the spool to pull it up thru the top of the valve block. The spool has a bunch of grooves machined around it's circumference.

I would guess there is either something wrong with the centering assembly, like the bolt that holds the washer in place has come loose and is setting in the bottom of the end cap keeping the spool from going down. Or there is a piece of crud in the valve body hanging up between one of the grooves and the valve body keeping the spool from moving in one direction...

 

[johneic]

There will also be another Oring

I need new orings on hand? of a special size?

 

[RonMar]

I need new orings on hand? of a special size?

You usually don't have to replace them, only if they are damaged. Not sure of the specific size, but you can probably take one to a hardware store or hydro shop for matchup if you need to replace one...

 

[erj]

John,
Here are a couple of pictures from my JW03 that may help along with RonMar's words.
RonJ

 

[psj12]

I just completed a 300' ditching project with my LW-7/Kama 554 combination with no mechanical problems. I had modified the BH to be powered by the tractor remotes. This was the BH's first intensive use even thougth I have had it several years. I purchased a narrow bucket from CircleG some time back and that is when I found out not all LW-7s were built at the same place or to the same specs. I purchased my BH through Artrac and the bucket from CircleG didn't fit. Artrac had to order one from the original factory from whih he ordered the BH.

I think the largest and most consistant complaint with all the LW series BHs is the lack of throttleing in the control valves. That is, they are very jerky in operation. After some practice they are better but definently need improvement.

 

[RonMar]

Great pics as always Ron

 

[johneic]

J

Thanks for the pics, Ron, I am going to tackle this today or tomorrow, my control valve in question
1) comes up (as in up above the operator station) and is "springy"
2) goes down only a little bit and has no to little spring return

So I assume I have some kind of debris at the bottom (right hand side of pic)

I plan to take this apart as shown in pic and look for (a cup seal? or such) in that pocket/cup at the bottom (right in pic)

Any help would be appreciated (like your home & cell phone numbers, best time to call, just kidding):laughing:

 

[RonMar]

Thanks for the pics, Ron, I am going to tackle this today or tomorrow, my control valve in question
1) comes up (as in up above the operator station) and is "springy"
2) goes down only a little bit and has no to little spring return

So I assume I have some kind of debris at the bottom (right hand side of pic)

I plan to take this apart as shown in pic and look for (a cup seal? or such) in that pocket/cup at the bottom (right in pic)

Any help would be appreciated (like your home & cell phone numbers, best time to call, just kidding):laughing:

The only seals you are going to find in there are the two pictured O rings. There is a groove or step around the central bore that the spool rides in. The O rings set in these steps and are gently compressed by the end caps. I am guessing that you are going to find the centering spring hardware setting loose in the bottom cap. If you need a phone consult, PM me your number...