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1995 F800 manuals, schematics, etc?

John V · 2021-02-15 19:11

Hello, Does anyone have wiring schematics, fuse box diagrams, or user manual they can share with me for a 1995 F800 (8.3 cummins)? I purchased a CD service manuals for "Body/chassis" and "powertrain/drivetrain", but I haven't found any sources for wiring diagrams yet.

Replies22
  1. #1John V2021-02-22 18:03

    Ended up buying a CD of the service manuals on ebay. Really awesome fully searchable PDF on it. If anyone finds this post and needs information in the future, feel free to message me.

  2. #2John_87912021-02-22 22:25

    Not sure what your issue was but we had an F800 90 or 91 with hydraulic brakes and that was a nightmare system to work on there’s a large valve body for lack of a better term that was bad and the dealer diagnosed it for about $1200 but they have a specialized set of gauges that hooked up to a bunch of ports simultaneously in order to diagnose it. The brakes I’ve never worked right for more than about six months at a time on that truck. At this time I still have it and basically can’t sell it because the brakes won’t work so I guess I’ll be keeping it!

  3. #3John V2021-02-22 22:44

    Fortunately mine has air brakes. Weirdly enough both low air pressure switches on the brake pedal are leaking. Hoping it's just bad luck and not something worse that would make them both go bad.

  4. #4John V2021-02-23 21:06

    If anyone has access to a parts manual, I could use help finding a heater core that fits a truck WITH factory A/C. All the ones i'm finding are fitting for without A/C. Attached is an image of the heater core sticker, but of course the Ford p/n is wore out.

  5. #5heymccall2021-02-24 19:31

    Go on Rockauto and look at 1985 F150 heater cores. Your picture doesn't help, as I can't see the port configuration. But, the dash is the same as an '85 pickup, so, I'd start there.

  6. #6John V2021-02-24 20:37

    Heater core width 7 1/4", height (the actual fin part) 7 1/2", thickness 2". 5/8" tubes. APDI/PRO 9010205 listed under '85 f150 looks like a match. My local advance auto has a heater core Carquest 398247 that looks the same, going to check it out and compare them side by side. Thanks so much for the advice!

  7. #7John V2021-02-27 11:33

    Anyone know where the coolant temp sender is on this truck? It’s a R/W wire to the dash. The manuals don’t point where it is. The Ford and Cummins dealers can’t say where it is. My coolant gauge doesn’t do anything, so I’d like to check if the sender is working but I don’t know where it is. (I’m suspecting it was removed but who knows)

  8. #8John V2021-02-27 13:32

    Yet another question: I changed out the fuel filter. The one on there did NOT have a small seal around the stud. The new one came with a seal. I put the seal on with the new one, and the filter is leaking. I have looked at parts diagrams and the diagrams show a slot in the stud for the seal to ride in. My stud does not have this slot. I'm guessing I should just install the filter without the seal. Anyone have experience with this?

  9. #9heymccall2021-02-27 13:53

    When the belt would break on my old F800, it would slap the wire off the sender. Top center front, one wire, slide on terminal. I'll have to look for pics.

  10. #10John V2021-02-27 23:58

    I'll poke around there tomorrow. Was that on the 8.3 6cta?

  11. #11John V2021-02-28 11:29

    Found it. Bottom sensor on the block behind the oil filter.

  12. #12John V2021-03-02 22:46

    So there seems to be an air brake leak when I apply the brakes. I had a buddy step on the pedal while I was under the hood. Seems to be pouring out of the governor. My understanding of the governor is it has two air lines, one to the air dryer to purge it when it reaches cut-off pressure, and one to the supply tank to measure the air pressure there. I don't see why an air leak would happen in the governor while pressing the pedal. There was another oddity, this little 1/4" air hose coming through the firewall to no where. I tried tracing it back under the dash, the only other 1/4" green line under there goes to the dual needle pressure gauge, which works. When applying the brakes a stream of low pressure air leaks out of this 1/4" hose (you can plug it by putting your finger on it). Any idea where this is intended to lead to? Wish it was easier to investigate all the hoses under the dash, but everything is bunched up there pretty tight.

  13. #13Old Doug2021-03-03 07:41

    The green line is a vent so when air needs to be released it dosent blow in the cab. You sure its the govener not some were close by it?

  14. #14doublewide2021-03-03 19:14

    Yes, vent. On my truck it vents the trailer hand brake.

  15. #15John V2021-03-03 19:43

    So what exactly is it doing when you say venting? When pressing on my brake pedal, quite a bit of flow is coming out of the 1/4" vent tube. The leak is definitely not coming from the governor. I messed around with it more tonight and the leak is coming from one of the air lines after it gets packaged up in a loom together. Looks like I'll have to separate them out and narrow it down.

  16. #16Old Doug2021-03-03 21:32

    Bad foot valve?

  17. #17doublewide2021-03-04 05:25

    When you step on the brake pedal you pressurize the system. No air should be exiting the vent tube. When you release the pedal the air pressure ‘vents’ from the system. Pull the dash gauge assembly and find out where the vent tube goes. Likely your problem is downstream from there.

  18. #18John V2021-03-14 11:29

    Might anyone have a picture of the configuration of the AC components on an F800 in this era? Mine is missing some components, namely the accumulator and some manifold hoses, and google searches are turning up differently shaped accumulators than what the service manual has. Rockauto's suggestion of accumulator doesn't look like the service manuals. The service manual's accumulator looks like an 83-93 f150. Wondering if the suction hose from the f150 would work too...

  19. #19Ctee19042025-04-22 19:19

    Hi, I am new to this forum and I don't know if this is the proper way to message you but I don't see another way. I am trying to see a wiring diagram for the fuse box and harness behind it for a 1995 F800 CAB any chance you can help me please?

  20. #20Ctee19042025-04-22 19:45

    Any help is appreciated [email protected] wiring diagram for 1995 F800 Ford Cummins Turbo Diesel CAB not COWL someone chopped up wires in harness under driver dash to fuse box and ignition. Thank you, Chandra

  21. #21Ctee19042025-04-22 20:11
  22. #22bill_tn2025-06-11 22:04

    Looking for a 1996 same model. Trying to find decent wire schematics.