Hi Folks, I am working on diagnosing and repairing a 1979 JLG 80F Telescoping Boom Lift. Right now there is one electronically controlled solenoid valve for the "lift" function. It is part of the Racine Proportioning valve assembly. The ground wire for the solenoid broke off and parts are unavailable for this model. However, after talking with United Rentals and looking at the schematics for 80H and 80HX models, it looks as though 80H possibly uses the same Racine valve body and possibly has the same individual solenoids. Could anyone confirm whether or not the solenoid valves are the same on the 80H and the 80F? Currently I am dealing with a wiring problem and a bad control module at the basket controls. After that is sorted, I'll be looking into the solenoid issue. I have not removed the solenoid yet. It will probably be a couple weeks before I can get back to it. Image of Racine valve body on the 80F https://drive.google.com/file/d/1n9jL-ET9vM-shqiqQFwxOI_NhoS6blpc/view?usp=sharing Image schematic of 80H Racine valve body https://drive.google.com/file/d/1zFxtgqjyr-0HWebW9oDKGTCqmsFk-1Ds/view?usp=sharing
I know there was a difference in the value (resistance) of the later coils on "H" series compared to the earlier coils on "F" series. As long as it's early production H, you may get away with it. Compare part numbers maybe? The Racine part number for the "F" series coils is #493871 The JLG part number for those coils is 7000406 If you Google the JLG part number, you will get some hits.
I've been doing some more research. I found a page in the 80F parts manual pointing to the valve assembly. Number 16 is the valve assembly it mentions they are 7.5 Volt valves - part number 4640347. Don't know if that is the assembly or the one solenoid valve. I haven't seen a part number for the coil for the 80F The 80H solenoid coil part number is 1420003 and it is also a 7.5v coil. I am thinking, unless they want more or less current to run through the coil, the resistance should be the same. Curious, where did you get the part numbers you listed? I can't get much detailed information on the 7000406 number other than a price. The 80F also has a part number related to the valve 7000407. Don't know if that is the assembly or solenoid either. Haven't found any information at all on the 493871 part number. I thought a zero may have been missing so I also tried 4930871 but that didn't return anything either.
I believe the 7.5 volt coils you mentioned are the later model ones that don't work on "F" series lifts. Here's the Racine manual on the proportional valves used in the JLG "F" series. The difference is in the model of controller used. Does your 80F use Racine or PQ controllers?
On the circuit board it says PQ controls.
Well, that gives you another option at least. If you can't find any of the JLG #7000406 coils that go with "F" style PQ controllers, you can always go to the "7.5V" coils with an 80H controller.