Forums
New posts
Search forums
What's new
New posts
New media
New media comments
New profile posts
Latest activity
Media
New media
New comments
Search media
Members
Current visitors
New profile posts
Search profile posts
Log in
Register
What's new
Search
Search
Search titles and first posts only
Search titles only
By:
New posts
Search forums
Menu
Log in
Register
Install the app
Install
Forums
Bobcat Skidsteer Forums
General Bobcat Skidsteer Forum
Bobcat 853 - front auxiliary valve only works in one direction
JavaScript is disabled. For a better experience, please enable JavaScript in your browser before proceeding.
You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an
alternative browser
.
Reply to thread
Help Support SkidSteer Forum:
Message
<blockquote data-quote="ags_virginia" data-source="post: 119244" data-attributes="member: 21671"><p>Hi, I recently purchased a Bobcat 853 (SN# 510126350) equipped with the Apitech front auxiliary control valve, but discovered that the valve only operates in one direction. Front auxiliary electronics are working fine, and both solenoids receive 12V power when function is triggered by the switches. I also ruled out the solenoid malfunction by swapping the solenoids. There is no audible change in engine / load when malfunction is observed, and so it seems the problem is with the valve body itself. </p><p></p><p>The service manual is silent with respect to "rebuilding" the Apitech valve, which is now obsolete. The parts diagram shows the solenoids (#27) and pilot orifice (#26) as separate parts, and also states that the replacement solenoids have an an orifice build-in and the separate orifice (#26) needs to be removed when replacing the solenoids. In my assembly, the orifice is built into the solenoid (tiny ruby orifice), so I imagine it was replaced at some point. I tried to see if maybe there was an old separate orifice left in the assembly which could be plugged, but nothing fell out of the solenoid port, and I could not pull anything out with a seal pick. </p><p></p><p>I am speculating that the following root causes could exist:</p><ol> <li data-xf-list-type="ol">Pilot port delivering hydraulic fluid to the spool is obstructed</li> <li data-xf-list-type="ol">Spool rod is obstructed / has high resistance in one direction</li> </ol><p>My options as I see them, are:</p><ol> <li data-xf-list-type="ol">Tear down existing valve, and attempt repair by cleaning / blowing all the passages with compressed air, and and replacing whatever seals I can still source from Bobcat, McMaster, etc.</li> <li data-xf-list-type="ol">Contact Parker (who purchased Apitech) and see if they have some alternative valves in the same form factor</li> <li data-xf-list-type="ol">Replace with a different directional valve (i.e. Eaton) that matches or exceeds specifications of the original Apitech</li> </ol><p>I am wondering if anyone else has observed a similar issue, or has recommendations on rebuilding these units in the absence of readily available parts. I will appreciate any advice on the matter.</p><p></p><p></p><p>[ATTACH=full]1956[/ATTACH]</p><p></p><p></p><p>[ATTACH=full]1958[/ATTACH]</p><p>[ATTACH=full]1959[/ATTACH]</p></blockquote><p></p>
[QUOTE="ags_virginia, post: 119244, member: 21671"] Hi, I recently purchased a Bobcat 853 (SN# 510126350) equipped with the Apitech front auxiliary control valve, but discovered that the valve only operates in one direction. Front auxiliary electronics are working fine, and both solenoids receive 12V power when function is triggered by the switches. I also ruled out the solenoid malfunction by swapping the solenoids. There is no audible change in engine / load when malfunction is observed, and so it seems the problem is with the valve body itself. The service manual is silent with respect to "rebuilding" the Apitech valve, which is now obsolete. The parts diagram shows the solenoids (#27) and pilot orifice (#26) as separate parts, and also states that the replacement solenoids have an an orifice build-in and the separate orifice (#26) needs to be removed when replacing the solenoids. In my assembly, the orifice is built into the solenoid (tiny ruby orifice), so I imagine it was replaced at some point. I tried to see if maybe there was an old separate orifice left in the assembly which could be plugged, but nothing fell out of the solenoid port, and I could not pull anything out with a seal pick. I am speculating that the following root causes could exist: [LIST=1] [*]Pilot port delivering hydraulic fluid to the spool is obstructed [*]Spool rod is obstructed / has high resistance in one direction [/LIST] My options as I see them, are: [LIST=1] [*]Tear down existing valve, and attempt repair by cleaning / blowing all the passages with compressed air, and and replacing whatever seals I can still source from Bobcat, McMaster, etc. [*]Contact Parker (who purchased Apitech) and see if they have some alternative valves in the same form factor [*]Replace with a different directional valve (i.e. Eaton) that matches or exceeds specifications of the original Apitech [/LIST] I am wondering if anyone else has observed a similar issue, or has recommendations on rebuilding these units in the absence of readily available parts. I will appreciate any advice on the matter. [ATTACH type="full"]1956[/ATTACH] [ATTACH type="full"]1958[/ATTACH] [ATTACH type="full"]1959[/ATTACH] [/QUOTE]
Verification
Post reply
Forums
Bobcat Skidsteer Forums
General Bobcat Skidsteer Forum
Bobcat 853 - front auxiliary valve only works in one direction
Top