What time is it?

[REDD]

I had posted a while back regarding whether the hourmeter was just a clock, or some sort of rpm-dependent meter. I had stated that I had contacted Kubota and they said it was just a clock. But......this past weekend I did a little experiment and found that for one hour of real time, the hourmeter logged one hour and 55 minutes. During that time the tractor, in real time, ran a half hour at idle and a half hour at about 1500rpm. I also tried timing a tenth of an hour on the meter. That took 9 minutes of real time. Something's fishy here.

I'm going to my dealer next month for a Kutbota-sponsored event. I'm going to show them the email they sent me and tell them about my actual findings. I'm looking forward to the discussion. What I witnessed would explain why, when using the hourmeter as my wristwatch, I always managed to show up late at the house.

 

[Bird]

I don't understand this at all. You say

for one hour of real time, the hourmeter logged one hour and 55 minutes

. In other words, the hour meter was running faster than your watch? I don't hardly see how that could be unless you able to run a lot more RPM on the engine than PTO speed. Then you say

I also tried timing a tenth of an hour on the meter. That took 9 minutes of real time.

In other words, one tenth of an hour (i.e., 6 minutes) on the hour meter actually took 9 minutes on your watch. OK, that might make sense if we knew what RPM you were running the engine, and you were only running the engine at two-thirds of PTO speed.

What model Kubota do you have? When you asked Kubota how it worked, did you tell them what model you have? What is the PTO RPM for your model? What RPM were you running for your experiments?

 

[JLoaf]

My hour meter on my ZD21 "clicks" and I can see something moving on the far right side of the meter with the key on and engine off.
I thought the hour meter was RPM dependent until I noticed this.
I'm still not sure what is going on?

 

[Bird]

My hour meter on my ZD21 "clicks" and I can see something moving on the far right side of the meter with the key on and engine off.

So did the one on my 1995 B7100, which had no tachometer, and was simply an electric clock. But of course, I didn't have that click on the 1999 B2710 because the hourmeter was geared to the RPM.

 

[Taiser]

Mine is just a clock, I checked! B7800.

 

[RobJ]

I saw the posts about this a while back. I've never heard on a certain RPM thing. When i worked on engines an hour of meter time meant 60 minutes, idling or full load. And when I rent a dozer or back hoe, an hour is an hour.

 

[MrJimi]

I know its not a tractor.. but in the aviation hour meters are activated by oil pressure and in the boat I had it was electrical with key on thing
and on my Yazoo it was with the key
Jim

 

[REDD]

OOPs. My mistake. I meant to say that one hour on the machine was the same as 1 hour 55 minutes of real time. Sorry.

 

[StrangeRanger]

Ahhh... this would explain why my wife was so pissed when I finally came in on Saturday thinking I had been out on the tractor for like 3-4 hrs and it was actually over 6 hrs! LOL I was beginning to think my 3400 HST had a time warp on it!
j

 

[RobJ]

OOPs. My mistake. I meant to say that one hour on the machine was the same as 1 hour 55 minutes of real time. Sorry.

Well that goes along with what I've heard here. It doesn't register until you reach a certain RPM. I don't like it but I think that's the way it works.

Rob

 

[Bird]

OOPs. My mistake. I meant to say that one hour on the machine was the same as 1 hour 55 minutes of real time. Sorry.

Sounds perfectly normal then, assuming you were running the engine barely over half of PTO speed. Personally, I prefer that type of hourmeter (or proofmeter, as some call it) because I think it more accurately tells you about the time on the engine. Many airplanes have that type of meter, and of course, some airplanes have both kinds of meter.

 

[BillG_in_TX]

It doesn't register until you reach a certain RPM. I don't like it but I think that's the way it works.

Rob

Rob,

It DOES register, but only at a fraction of the clock time. One hour on your watch will only register one hour on the meter if the engine is running at PTO speed (e.g 2800 RPM). If you are running the engine at 1400 RPM and full PTO speed is indicated to be 2800 RPM, your meter will show .5 hours after 1 hour of "real" time.

 

[REDD]

I checked my e-mail and found I had not told Kubota my model number at the time, not thinking it would have anything to do with the answer. As their answer clearly doesn't match reality, it's strange that they wouldn't have qualified their answer if there were two types of meters on the whole Kubota line.

 

[BillG_in_TX]

I checked my e-mail and found I had not told Kubota my model number ...

REDD,

You haven't told us your model number either!

 

[REDD]

I am really off my mark today. I'm trying to post on this board in between tasks at work. Luckily my job isn't suffering as poorly. I have a B3030.

 

[RobJ]

Rob,

It DOES register, but only at a fraction of the clock time. One hour on your watch will only register one hour on the meter if the engine is running at PTO speed (e.g 2800 RPM). If you are running the engine at 1400 RPM and full PTO speed is indicated to be 2800 RPM, your meter will show .5 hours after 1 hour of "real" time.

I really wonder the reasoning they came up with this. OR are we making up the reasons for Kubota instead...trying to rationalize for THEM. Maybe it's the simple fact it's really a speedometer converted to hours to save money. So an engine working hard at 1500 rpm shows less time than engine not loaded at 2500 rpm, like driving down the highway. Yeah, its a speedometer!!

 

[john_bud]

I really wonder the reasoning they came up with this. OR are we making up the reasons for Kubota instead...trying to rationalize for THEM. Maybe it's the simple fact it's really a speedometer converted to hours to save money. So an engine working hard at 1500 rpm shows less time than engine not loaded at 2500 rpm, like driving down the highway. Yeah, its a speedometer!!

Robj,

My 1963 ford has a proofmeter. It it an RPM counter that is correlated with time at the specified PTO speed. That same setup was used on the older tractors going back to the 8N's (and prior?). It is IMO, vastly superior and more expensive method of determining the amount of engine work performed. A pure clock meter is about $5 where a proofmeter is $50-100.

If you prefer the extremely cheap and inaccurate method of determining the amount of work by counting the time the ignition switch is on, you can add a supplimental meter to do just that. In fact, having a pair of meters (one of each type) is better than having either one alone. In aviation, that is called engine hours and air frame hours.

But tell me, if you rent a bulldozer and push the stop button to kill the engine, but leave the key on and still counting hours, would you still be a fan of that type of primative hour meter?

Should you, or anyone else, want to learn more about hour meters, there have been many discussions. A quick search will yield a lot of results.

jb

 

[kwolfe]

But tell me, if you rent a bulldozer and push the stop button to kill the engine, but leave the key on and still counting hours, would you still be a fan of that type of primative hour meter?
jb

I agree with you that both wouuld be the ideal situation, however take an example of a tractor that has been used for mostly dirt work. I saw an L3130 for sale with FEL & BH. The add says it has 400 hrs on it, mostly from dirt work. Now from reading other threads, people who have larger machines do not typically run them at PTO speed when doing loader work most run a little above idle). Therefore, this tractor could have upwards of 700-800 actual hours of hard dirt work done with it? I would want to know that up front.

Your airplane analogy is perfect in this situation, except a tractor would have engine hours and "rest of tractor" hours.

 

[john_bud]

On the dirt work. Was that FEL work at a less than PTO engine speed, or pulling a 2 bottom plow thru hard pan at full PTO speed?

Here's my OPINION (was going to say $0.02 - but it's probably not worth that much!)

I use a loader tractor in 2 modes. At 2000 RPM to casually move dirt, snow, mulch and other fairly light and easy activities. Any lower rpm and the hydrualics are way too slow to be useful. I also run at full PTO speeds and then some 2600 to 2900 rpm (pto is 2600). I do that to have the hydraulics as fast as possible and to be able to move as much dirt, gravel or back hoe spoils as possible in as short of a time as possible.

In mode 1, 400 meter hours may take 400*2600/2000 or 520 clock hours. In mode 2, 400 meter hours may take 400*2600/2900 or 359 clock hours. My thought is that the longer slower gentler use would have less wear and tear on the tractor than the shorter duration but more intense use. Even though the number of engine revolutions is exactly the same.

It would be interesting to have both types of meter running. Say, here's a thought. Why not put a seat switch activated clock type hour meter on the machine. Then you can have an indication of "seat time".


Then again, the meter I use to judge when it's time to come in goes from F to E...

jb

 

[Marcussen]

I discovered my hour meter was actualy an RPM counter when I went out to do some work and I told my wife I would be back after two hours. Watching the hour meter made me late for dinner since I was working 400-500 rpm below the PTO rated RPM.

I looks like Kubota figured this into the maintenance schedule so I don't have a problem with it. Now I also wear a watch for actual time.