Backhoe Jinma 354 backhoe won't extend

[newt88]

Jinma 354 backhoe won\'t extend

The lower arm will not extend. I took the hoses off and I can move it manually. When I turn the pto on the hydrolic cylinder fills but will not move. Is there a problem with my vavle. I welcome any ideas on how to find and fix the problem.

 

[JohnS]

Re: Jinma 354 backhoe won\'t extend

Assuming you have a Guilen 3pt (sp?) which I believe is very similar to the Jinma frame mount, your control valve probably looks like: http://johnstractor.com/files/backhoe8.jpg

As far as I know, there is only one pressure relief valve for the entire hoe. As long as you have working force on the other cylinders, the relief valve is probably OK.

My initial guess would be you have blown seals within that particular cylinder. To isolate it you would need to swap hoses with a known good cylinder. The easiest place to swap, is at the control valve. Make sure you have everything supported well, when you take pressure off cylinders. ie be very careful. If problem stays with cylinder, it is cylinder or those particular hose. If it stays with the original bank, probably in that particular valve.

I hope this helps, but just for clarification, I have not had to perform this on my hoe, but it is the method I would use if I had a similar problem as you.

Add: There is another method just to test for blown seals. Post if you would like me to try to explain.

 

[newt88]

Re: Jinma 354 backhoe won\'t extend

Thanks that makes sense I'll let you know how it works out.

 

[SPIKER]

Re: Jinma 354 backhoe won\'t extend

NEWT:
John had great IDEA but I think I would swap the hole cylinder out for one of the outrigers (if it is like the JWO3 which uses all the same cylinders) I had to swap one of mine when I broke the clylinder off a the end! /forums/images/graemlins/blush.gif the broken one is now re-welded and working the elbo part where as it did operate the hole arm. (should have swapped it for the outrigger but had to pull the elbo one to get the arm one out anyhow so just swapped them and mounted the broken one up top and welded it (broken rod end) in-place on the bushings. that kepts it aligned with no binding after welding.

MarkM

 

[newt88]

Re: Jinma 354 backhoe won\'t extend

Thanks I am pretty sure I busted the seal in the cylinder. I was skidding trees and I must have backed into one. I will get back to you with results later I am going to wait to fix it. More trees to skid.
Newt