Hour Meter

[ghobday]

Has anyone rewired the Hour meter on a B7100 so it only operates when the engine is running? It seems the hour meter operates as long as the key is in the operate position and continues to run if the engine stops. I think I need a normally open contact switch connected to the oil pressure system that will activate the hour meter only when the engine is running.
Does anyone know if Kubota has an oil pressure switch that closes with pressure?

 

[Bird]

ghobday, I don't know of anything or anyway to change the hour meter on the B7100. I used to have one and the hourmeter is simply an electric clock that runs, as you say, when the key is on. Of course, that means it registers an hour in an hour's time whether you are idling or working at full RPM. In contrast, some other tractors, such as my B2710 have hour meters that are tied to engine revolutions, so it registers an hour in an hour at PTO speed, but would only register half an hour in an hour at half that engine speed. You mention the hour meter continuing to run if the engine stops. You do turn off the key when you kill the engine, don't you? That stops the hour meter.

Bird

 

[WVBill]

I need to do some troubleshooting on the hour meter on my B6100 as it doesn't work at all right now.

Interesting, though that it is supposed to run whenever the key is in the "on" position. I can take the key completely out of my B6100 and the engine keeps running. Maybe that's why they changed the hour meter to run off the engine revs. Too many "low hour" used Kubotas got that way by running around with the key removed? /w3tcompact/icons/wink.gif

 

[bpence]

I really wonder how many Kubotas are showing the low hours 'cause you can run them without the key. I can turn my B7100 off and pull the key and it just keeps on running........maybe I should do that more often. Sure would keep the hours real low. Of course, you don't get any headlites. Of course, you can do that with many diesels.

On the flip side, the guy I bought mine from apologized when I was looking at the tractor because it had an extra 100 or so hours on the meter. Seems the first day he had it, put it in the shed after mowing, pulled the throttle back and killed the motor. 5-6 days later he went to start it and it was totally dead. Also noticed/realized he had another 100 or so hours on the meter versus what he remembered when he parked it. So, if you don't turn the key off you can just slowly run the battery down. Poor guy.....his wife made sure I knew how stupid she thought that was and she made sure she told my wife too, in case I decided to get stupid.

Bob Pence

 

[Bird]

WVBill, on a lot of diesels, the "kill' switch is a manual fuel shut-off that has nothing to do with the electric system. Such was the case with my B7100, your B6100, and many, many others. I think more and more tractors are going to the electric solenoid that shuts off the fuel when you turn the key off, as do most, if not all, the diesel cars and pickups. As you said, you can turn off the key and remove it and the engine keeps running. The problem with that is that if you're using any electrical equipment, such as lights, your alternator or generator is not charging the battery, so you can run it down without realizing it. Of course, killing the engine and leaving the key on may get a similar result.

Bird

 

[Bird]

Bob, looks like we were typing at the same time, and saying something similar, you were just faster than me./w3tcompact/icons/laugh.gif

Bird

 

[bpence]

Must be great minds think alike, or something like that.

Bob Pence

 

[GlueGuy]

Does the B7100 have an oil pressure indicator? If so, trace that back to the pressure sender. Once you've found where the sender is, you can re-plumb the fitting to have a "T". Put the sender back in one side, and a Hobbs pressure switch on the other. Then re-wire your hour meter through the pressure switch. That's the way it works on my airplane.

The GlueGuy

 

[RIRICH]

For years gasoline fuel injection has been using dual purpose oil psi switches. One would read psi and the other would close the the fuel pump relay circuit. Adding an extra sending unit from a idiot light set-up will do the trick, but I do suggest using a relay, and fused circuits. It will not only be safe and "proper" but be better than some factory jobs.

 

[WVBill]

Bird:

I don't normally run the tractor with the key out - just find that to be an interesting feature of a diesel engine: no electricity is needed to keep it running.

But your comment: " The problem with that is that if you're using any electrical equipment, such as lights, your alternator or generator is not charging the battery, so you can run it down without realizing it." made me think.

I just had to replace the battery in the B6100 just recently - it just would not turn the engine over (click, no crank, lights dim/out, sometimes not eve a "click"). I tried re-charging it but it would not take a charge so I replaced it and the new one cranks the engine fine.

I don't know how old the other battery was so it may have been just "wore out" but I'm wondering if there might be some condition in the tractor that caused it to die/discharge. There are only four electrical items on the tractor: The starter, the glow plugs, the headlights and the hour meter. I never run the headlights and I always remove the key when the tractor is not being used so that leaves the glow/start as the only user of electricity (other than possibly the hour meeter is mechanically failed and still drawing electricity when the switch is on).

But what if the generator is not working? How would I ever know - until the battery is fully discharged after some number of starts? How can I confirm that the generator is working? Any other thoughts on the cause of my dead battery?

By the way - on the key switch there are three positions: Left = glow plugs, Right = starter engage, and Center = "run". Does inserting the key complete the circuit for the hour meter or does engaging the starter lock in a relay for the hour meter that remains locked in until the key is taken out? I think it may NOT be the relay option because I do not hear any kind of click when I remove the key.

I guess I will dig into the wiring diagram when I get home this evening...

 

[MDNick]

A comment about that electric fuel shut-off soleniod. The L2850 I ran at the golf course had the electric soleniod shut-off. Normally the solenoid is not engaged and has the fuel on, when you shut down via the key, the solenoid gets pulled in long enough to kill the engine, then releases and turns the fuel back on. After replacing 3 solenoids we discovered that every time we washed it, water would get in somewhere and short out the circuit, pulling in the solenoid. That solenoid has a relatively short duty cycle, it cooked itself after a short time of being locked on. We had to unhook the solenoid from the linkage and use the mechanical system until we replaced the solenoid. 3 times. Ok, we were slow. After discovering the problem, we just pulled the fuse, washed it, and let her dry out. Guess we could have fixed it right but we found a workable solution that didn't require hunting down a short somewhere. The course super was incredible on patches to keep equipment up, but not much on long term fixes, oh, and we never had any money to fix it right.

After years of running Leroy (David BROWN 990) at home on the farm with a manual lever you had to pull out and lock to turn on the fuel and release to shut down, I thought the key shut-off was just the coolest thing.

Nick

Farmer kid usetabe, Farmer Wannabe

 

[GlueGuy]

<font color=blue>How can I confirm that the generator is working?</font color=blue>

You can put a voltmeter on the battery terminals. When the engine is not running, it should read a little over 12 volts. With the motor running (and the ignition switch on) it should read in the 14-15 volt range.

Oh, and my ignition switch has four positions:
1 - off
2 - run
3 - glow plugs
4 - start

The GlueGuy

 

[Bird]

WVBill, I guess GlueGuy has already pretty well answered your questions. A voltmeter at the battery terminals should read about 12.6 volts on a fully charged "12 volt" battery with everything turned off. With the engine running, it needs to register 14.2 to 14.4 volts. And to check to see if you have any battery drainage when it's not in use, I'd just use a clamp meter on the positive cable to see whether any amperage is being drawn. Of course, you can also use a clamp meter (turned the other direction) to see what amperage is being charged into the battery with the engine running, but in my opinion that really doesn't tell you a lot since you expect the amperage to fall as the battery approaches full charge.

Bird

 

[WVBill]

Thanks GlueGuy and Bird,

I tested the generator ("dynamo", according to Kubota) last night and the bad news is that the voltage was the same with the engine off as it was with it running.

So I got out my Kubota WorkShop Manual to see what it would take to replace the dynamo. ...Ulp...it looks like a pretty big job. The follwoing need to be removed to get to the dynamo: Air Filter, Muffler, Hood, Side Covers, Radiator, Cyninder Head Cover, Injection Pipes, Rocker Arm, Push Rods, Cylinder Head, Fan... and then the Dynamo.

I think I'm going to try to avoid that by:
1) Checking out the wiring and the rectifier in hopes that they have failed not the Dynamo.
2) Testing the Dynamo at the dynamo (The WSM says I should get 43V and 30.8V across the two pairs of leads - at "4,250 RPM". I didn't think that little engine could run that fast!!

If the Dynamo is, in fact failed, I may rig up one of those battery minder trickle chargers and just "plug the tractor in" whenever I put her away (fortunately I have electricity at the barn).

 

[skent]

I think thats supposed to be 4250 RPM on the dynamo. . . . (PLEEEEASE dont try to get 4250 out-a-the engine. . . . the only thing I've seen go bad on them is the bearings. Usually a charging problem is the regulator/rectifier, or corroded connections.

Let us know what you find. . . . . . good luck!

Steve

 

[Anonymous Poster]

Has anyone ever replaced their manual fuel cutoff lever with an electric solenoid powered from the key switch "Run" position?

I have a broken linkage for the kill lever that forces me to turn off the fuel at the cutoff valve under the hood. I was thinking it would be nice to replace the assembly with a solenoid so when I shut off the electricity, it turns off the engine as well.

I am hoping to find a low current draw solenoid that can be powered contunuously while the tractor is in operation so that the energized solenoid allows the fuel to flow and removing the power to the solenoid cuts off the fuel (opposite to the type of solenoid MDNick had on the L2850).

-Mike

 

[Von]

There is one one ebay Item #1602451573 that ends in a few hours. It looks like the one on the back of the fuel pump on the B2710. Take a look at it.