Help - TC40D PTO Indicator Lights

[wolfpack2]

After 8 hours of digging and moving dirt, the PTO speed indicators (540 or 600 depending on engine speed) started illuminating even with the PTO off. Also the PTO indicator light does not illuminate now when I engage the PTO. I looked underneath to check for pulled out wires, but I don稚 see anything obvious. I was hoping someone here might be able to point me in the right direction. I still have 120 tons of stone to move and don稚 like operating the tractor if it is having electrical issues.

 

[LoneCowboy]

Having had this happen, don't drive the tractor anymore, it will die on you and pretty soon it will think the PTO is on and kill the motor and then it's stuck in the field
You can replace the switch itself (under the lever, you reach it from underneath, snaps right in), but that isn't the underlying problem, but it will fix it for a while. Something else is wrong that causes this.

http://www.tractorbynet.com/forums/nh-buying-pricing/104396-do-not-buy-tc40-45-a.html

hope it's still under warranty.

 

[jinman]

After 8 hours of digging and moving dirt, the PTO speed indicators (540 or 600 depending on engine speed) started illuminating even with the PTO off. Also the PTO indicator light does not illuminate now when I engage the PTO. I looked underneath to check for pulled out wires, but I don稚 see anything obvious. I was hoping someone here might be able to point me in the right direction. I still have 120 tons of stone to move and don稚 like operating the tractor if it is having electrical issues.

I believe Lone Cowboy (Bryan) is mistaken about the problem you are having. I believe your problem is not from a switch, but rather is that the tachometer circuit is not sensing the 540 or 600 PTO rpm properly. That should all be a problem within the instrument panel electronics or in the tachometer sensing circuit from the alternator. The PTO switch causes the PTO "ON" indicator light to come on, but it does not control the illumination of the 540 or 600 PTO rpm lights.

Engine rpm is sensed by a pickup probe at the alternator and sent to the tachmeter. On the back of the instrument panel, there is a little switch that has the numbers 0-9 beside it. That sets the point the PTO rpm indicator should come on for your tractor. Yours should be set to "0". Evidently, this circuit is used on more than one tractor and that's why the switch has several settings.

My guess is that moisture has condensed inside your instrument panel and is causing this problem. I'd bet a new instrument panel will solve this issue. Have you noticed any erratic movement of the tachometer also? It could also be effected.

 

[wolfpack2]

Thanks Brian and Jim. After a few hours out in the barn, I got the backhoe and loader off and started searching for the root cause. Unfortunately the warranty expired years ago as the tractor is 6 years old and has 620 hours on it now, so I am on my own unless I want to pay for it. But is has served me well with only a few issues that were not a result of my misuse and abuse. For those the dealer and NH have been very good to me in getting them fixed. Even out of warranty for the front ring gear coming unbolted as it was an obvious build issue (missing lock washers on the ring gear bolts).

Well, I found the problems. Yes there was more than 1 issue causing this. First, the connector on the PTO switch had come part way off the switch. The retaining clip broke off a couple of years ago when a log smashed the switch and connector. The connector was also corroded, so I cleaned it and put some dielectric grease in it to prevent any future corrosion. This did not fix the RPM indicator lights. So out comes the cluster and guess what. A few mice had decided to eat some of the insulation off the back of the cluster and some of the wires. So I taped up the wires, cleaned up the mouse mess and put wire loom over the wire harness to stop any future chewing or at least slow them down (I hope). All seems to be working OK at this point. Well I had it apart I decided to put some dielectric on the other connectors as they also appear to be getting oxidized. I figure it can't hurt and may even prevent me from being stuck out in the field with it.

Jim the cluster appears to be OK for now and the tach has been stable all the time this was occurring, but I did notice that the switch on the back was set at 1 for mine. I think this is possibly a calibration feature for the tach or because mine is a 40 vs. your 45. All I know is the 540 light comes on at 2600 RPM, so I am leaving it as is. I will have to keep an eye on the cluster as it does fog up like all the other Boomers of this vintage. Have they fixed this on the DA models or do they fog up as well?

 

[jinman]

Jim the cluster appears to be OK for now and the tach has been stable all the time this was occurring, but I did notice that the switch on the back was set at 1 for mine. I think this is possibly a calibration feature for the tach or because mine is a 40 vs. your 45. All I know is the 540 light comes on at 2600 RPM, so I am leaving it as is. I will have to keep an eye on the cluster as it does fog up like all the other Boomers of this vintage. Have they fixed this on the DA models or do they fog up as well?

Although the Repair Manual does not say it, the "0" setting must be a starting point for the 540 light setting. Maybe they set it on zero, then bring the engine up to 2600 rpm and see if the light comes on. If not they adjust up a notch. I've never done this, I was just reading and quoting the manual. It is for all Class III Boomers, so it should be more specific. In many areas like this, the details are missing.

I'm sure glad you found you problems. As hard as it is to get to that PTO switch, you'd think that nothing would ever get in there, but limbs always seem to find a way. ...and mice are such wonderful creatures.

 

[Soundguy]

I leave green bait sticks on my tractors all the time now.. Last time mice invaded they did a real number on my wiring.

Not to mention there is no experience quit like starting your tractor and hear a squeak, and a rumble, and then see a rat tail fly out and pass your face from the radiator fan area! ( Yuck! )

Soundguy

 

[lhfarm]

I keep baggies full of mothballs tied to the battery cables up front and inside the dash and joystick. I have damaged wires in all three places. Other than an occasional whif of mothball - not the most pleasent of smells - it seems to be keeping the mice away. I plan to refresh the bags this fall.

 

[jimg]

I know this is changing the topic but I appreciate the infos on mouse-proofing. I was thinking along the lines of mothballs myself but wasnt sure where to locate them.

Never thought of bait sticks. How do you place them and not wind up losing them while the tractor is working?

Also like the wire loom idea. Hadnt thought of that one.

I was also going to lay a 'trap line' in my barn and try to get them before my tractor and implements are invaded.

 

[Soundguy]

I know wlamart and publix carry the mothballs. would guess most rel grocery stores do as well, inthe detergent 'home' area.

On the bait sticks, they come in a big 4"x8" bar that is perferated to breat into uh? like 3 sticks that are about 1.25" x 8" .. I then break those in half to make 6 sticks. I then drill a small hole in each and wire tie them in various places.

Soundguy

I know this is changing the topic but I appreciate the infos on mouse-proofing. I was thinking along the lines of mothballs myself but wasnt sure where to locate them.

Never thought of bait sticks. How do you place them and not wind up losing them while the tractor is working?

Also like the wire loom idea. Hadnt thought of that one.

I was also going to lay a 'trap line' in my barn and try to get them before my tractor and implements are invaded.