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Recent content by J_Lin

  1. J

    1985 JLG 40H restoration time

    Has anybody performed a turret bearing wear tolerance measurement such as described in the 40H service manual? The spec called for is max 0.057" - I did the measuring and found a definite .090". This machine clock says 3500 hrs. The spec also says to replace the bearing if over the 0.057"...
  2. J

    1985 JLG 40H restoration time

    I pulled the other two controllers to test the potentiometers and I've got three controllers with dead spots and/or low ohms all over the map - I'm going to obtain some new ones and solder them in and then restore the wiring based on the PQ supplement book schematic. Hopefully the pwm converters...
  3. J

    1985 JLG 40H restoration time

    This is starting to make sense to me now, as I find it really difficult to follow the generic electrical schematics. The schematic Snorkel provided me with was outstanding. The construction company architect (at the time) fed the pdf file into his plotter and gave me a very large diagram with...
  4. J

    1985 JLG 40H restoration time

    Thanks for the tip!
  5. J

    1985 JLG 40H restoration time

    sorry for the lousy pic- not sure how to get that more clear
  6. J

    1985 JLG 40H restoration time

    Ok I finally got some time today and pulled one of the controllers to do some testing. The potentiometer definitely had a couple of dead spots but not surprised. This would cause erratic behavior and is sending me in a direction as to why they were disabled in the first place. I'm gonna have...
  7. J

    1985 JLG 40H restoration time

    Also, is it possible from the pic I posted to determine if indeed these are Racine valves?
  8. J

    1985 JLG 40H restoration time

    A few back I was talking with a snorkel tech regarding the ATB50 that I was correcting some hacked wiring amongst other issues. I was instructed to replace the high country drive card with an OEM that was shipped to the shop. In the meantime to move the machine I jumpered the coils in order...
  9. J

    1985 JLG 40H restoration time

    BTW I just realized you reside just next door!
  10. J

    1985 JLG 40H restoration time

    Hello! Thanks for your reply! I've got some time this morning and have been scanning through the older thread. There is so much info here and it is surprising how many old machines still in operation. I've got three PQ's and a manual steering valve. Ironically I worked with the mechanic that...
  11. J

    1985 JLG 40H restoration time

    Had some success! I had ordered the PQ tech supplement a while back and it finally arrived in the mail. This gives me the color codes for the operational wires out of the controller. Although the wiring is all still in the platform control box (what a mess!) the process of chasing what works...
  12. J

    1985 JLG 40H restoration time

    Hi all! My acquired '85 0r '86 JLG 40H is gonna get some TLC. sn// 0308509376 I've attached some pics showing what I believe are Racine valves and some excellent hay-wiring that should win some awards. I have the maintenance manual 3120240 as well as the parts manual. PQ controllers...
  13. J

    pic test

    test
  14. J

    Hello again been a while

    Hi again! I've been gone awhile with work and stuff but am back again with some JLG40H questions. I've been extensively reading many posts related to problems with these old machines and have many pages bookmarked for reference. Thanks to all for your help, much appreciated. I' m gonna have...
  15. J

    20 days, feeling neglected

    thanks barklee for the welcome - much appreciated! I used the machine for about a month at home to get a feel for it. I took a good look overall and feel that while there is a good bit of cleaning up to do on both lower and platform wiring, the replacement of the boom harness should not be...
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