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Subject: Question about proof meeter

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Dave Smith    Posted 02-23-2019 at 17:44:05 [URL] [DELETE]        [Reply] [Email]  
  • Question about proof meeter
  • Question about hour meter. If approximately 1600 RPM on the
    engine makes approximately 540 RPM for the PTO, does the
    1600 RPM advance the hour meter 1 hour? I have never
    seen this written anyplace.
    Dave <*)))><

    Tim Daley(MI)    Posted 02-25-2019 at 06:30:53 [URL] [DELETE]        [Reply] [No Email]  
  • Re: Question about proof meeter
  • Today's trivia question: Did Proofmeters ever come with a Kilometers Per Hour scale?

    Tim Daley(MI)

    Tim Daley(MI)    Posted 03-06-2019 at 18:35:20 [URL] [DELETE]        [Reply] [No Email]  
  • Re: Question about proof meeter
  • Answer: The September 1952 MPC lists two -8N-17360-A & A2 alternate(miles) and 8N-17360-B & B2 alternate (kilos)and NAA versions, FAA-17360-B (miles) and FAA=17360-C (kilos)

    Tim Daley(MI)

    Tim Daley(MI)    Posted 02-24-2019 at 07:34:31 [URL] [DELETE]        [Reply] [No Email]  
  • Re: Question about proof meeter
  • The A.S.A.E. ( American Society of Agricultural Engineers ) standardized things back in the day. First, the standard established for PTO speed is 536 RPM and thus was rounded off to 540 RPM. The established ASAE engine speed becomes 1580 RPM. These numbers are used to calculate readings with. Ground speed will vary depending on which gear is used. Also, the ASAE standard for belt pulley speed is 3000 to 32000 ft. per minute, or, 1316 RPM on Proof-meter. The Proofmeter (Tachometer) is detailed in the later 8N Operator’s manuals and subsequent NAA and Hundred Series model Operator’s Manuals. It is probably a chapter often skipped over but you have to read it and understand what it is saying. Here is the paragraph from the NAA manual and is the same as in the 8N manuals:

    “The hour meter portion of the Proof-meter represents the hours of engine operation. One hour shown on the hour meter represents one clock hour of tractor operation at 1580 engine RPM. Engine speeds below 1580 revolutions accumulate hours slower than clock hours. Engine speeds in excess of 1580 RPM register faster than clock hours.”

    I think Dogman is pretty close in the explanation. It also makes me wonder when I see an ad if the seller says, "...tractor has only 400 hours since engine rebuild..." if he is just reading what the Proofmeter shows or did he actually keep records of actual hours the tractor ran? The numbers are not the same thing as many are led to think.

    Tim Daley(MI)

    Jim    Posted 03-04-2019 at 08:28:57 [URL] [DELETE]        [Reply] [Email]  
  • Re: Question about proof meeter
  • Probably neither. At best most are just approximations. I use one tractor about 80 hours a year so for 3 1/2 years it is 280 hours. May vary but not by a lot.

    steveVa    Posted 02-24-2019 at 03:09:00 [URL] [DELETE]        [Reply] [No Email]  
  • Re: Question about proof meeter
  • My understanding is that a proof meter shows 1 hour for running qt 1500rpm for 1 hour.
    If you run slower it shows less. 750 rpm for an hour would show on meter as 1/2 hour.

    Ultradog MN    Posted 02-23-2019 at 22:31:50 [URL] [DELETE]        [Reply] [No Email]  
  • Re: Question about proof meeter
  • There's no time involved.
    People always say there's "xyz hours on the clock" but that's not the case.
    It's really about how many revolutions there is on the tractor.
    If you run the engine at 1/4 throttle it will take 4 hours to put 1 hr on the proofmeter.
    If you had an original proofmeter you could compute how many revs it had made since new. Hours it had run would be impossible to compute.
    Doesn't tell you anything about the engine either as those could have been rebuilt/overhauled along the way.
    Am just thinking out loud here.

    Farmer Dan    Posted 02-23-2019 at 21:27:57 [URL] [DELETE]        [Reply] [Email]  
  • Re: Question about proof meeter
  • Good question. I always assumed it counted hours like a clock. I don't know why rpm's would affect hours but then I don't know how them things work either.

    JMOR    Posted 02-24-2019 at 21:37:56 [URL] [DELETE]        [Reply] [No Email]  
  • Re: Question about proof meeter
  • It works like the odometer in old cars/trucks, in that the speedometer cable (in this case governor output cable) enters the proof meter & goes thru a gear reduction & that increments the Veeder-Root counter wheels.

    Jim    Posted 03-04-2019 at 08:31:01 [URL] [DELETE]        [Reply] [Email]  
  • Re: Question about proof meeter
  • Say What!

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