2004 John Deere 790 w/419 loader and #7 backhoe ..just turn 200 hrs .One week after backhoe was removed 3ph just drop when I was doing some loader work . 3ph was working fine earler that week (scraping the driveway). This tractor is keep out of the weather ... all service has been done by me inclunding 50 hr ...this tractor was bought new in July 2004 ,backhoe w/powerbeyound was added last year I've had the backhoe off twiced makeing sure that lines were clean and cliped together each time ...I changed hyd fluid w/filter and clean the screen (even thought it didn't need it ) hyd fluid is on the full mark...Loader, power steering and backhoe all work fine .... speed /drop valve is open and no bent hyd lines under or on tractor. I've looked at both bypass valves for trash(system,rockshaft relief)I pulled the rockshaft unit off to look inside for something wrong everything looked fine John Deere dealer was not much help only bring in and we will look at it said that it sounds like the rock shaft valve, about $1000.00 to replaces If that is the case I can order parts to rebuild it myself for under $100.00... any help would be appreated ...
Please help!!790 3ph stop working
- Thread starter tpike35
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RoyJackson
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- Joined
- Nov 17, 2001
- Messages
- 23,144
- Location
- Bethel, Vermont
- Tractor
- John Deere 4052R Cab,, Deere 855D UTV, Z920A Zero Turn Mower and assorted implements
I've got the tech manual and will take a look at it on Thursday (too late tonight...sorry).
In the interim, look at the rockshaft lever linkage.
In the interim, look at the rockshaft lever linkage.
Thanks Roy ...I,ve got a tec manual and everything with the leaver looks to be in working order to me that's why I took the unit off I though maybe something came loose inside the unit I did however notice that the main spool in the rockshaft valve was not toching the feedback arm , later on when I went to put the rockshaft housing back on the main spool was toching the feedback arm (I guess it must have bleed down or something , it was off about 6 hrs or so )..when I started the tractor up it sounded like the main spool was pulled back again ...I hope that this info helps..Thanks again !!! I'll be looking forward to hearing from you .
RoyJackson
Rest in Peace
- Joined
- Nov 17, 2001
- Messages
- 23,144
- Location
- Bethel, Vermont
- Tractor
- John Deere 4052R Cab,, Deere 855D UTV, Z920A Zero Turn Mower and assorted implements
Sent you a PM
well after rebuilding the rockshaft valve and replacing all the o rings in the rockshaft housing everthing is working fine ... only trouble is I didn't see anything wrong with the rings that I took off ... there was a little more wear than I though should have been on the feedback linkage tractor only has 200 hrs on it ... it took me a day and $62.50 in parts but well worth it !!! thanks for all the info ..Man it's nice have her back up and running again .....tpike35
