2072 Blowing fuse
 

Good evening. I have a 2072 which I use for cutting grass and plowing snow with. Mid summer I was cutting grass and the PTO shut off. Tractor kept running, but I shut it down to check things out. It then wouldn't start again. I towed it back to the barn and found that the fuse blew. So, I bought some new fuses. when they came, the tractor started right up and I resumed cutting grass. After about 5 minutes, the PTO shut off again and the tractor kept running. I drove it back to the barn and shut it off. Fuse blew again. I am not great with things electrical. I do have and no how to use a multimeter. How would I check the Indak PTO switch to see if that is the problem? What else should I be looking at? I appreciate any assistance you can provide. I'd like to get this fixed before the leaves start to drop.

Sounds like your PTO may be going bad or you have a wire that is shorting to ground.

Here is the PTO checkout procedure listed in our technical section.
https://www.onlycubcadets.net/forum/showthread.php?t=30

Here is the wiring schematic for your tractor if you don't have one.
https://www.ccpartsnmore.com/cub-cad...ing-schematics

Thanks for the information. I will try to have a look at it tomorrow. I did have the service manual with wiring diagram for the tractor, thank you. My PTO switch only has 5 prongs though, whereas the diagram shows 6. In the diagram, if it says in the "off" position "C+D" does it mean there should be continuity between C+D in that position? I took the switch off the tractor, so I can check for continuity, but not voltage at the moment. I appreciate your help. Can the PTO themselves be rebuilt, or would I be looking at buying a new one if it is going bad?

Yes, C & D will be closed when the switch is in the "off" position for the start circuit to work on the tractor.

New bearings can be installed in the PTO's but that's about it. If you need a new one this is the place to go. I would call them and see if they can help you out.
https://xtremeope.com/?srsltid=AfmBO...PzMHPHl2XVyJNJ

So, I picked up some fuses today. I disconnected the harness to the PTO, and when I turned the switch on, all gauges and lights turned on. When I started the tractor, lights and gauges all turned off, and when I checked the fuse, it was blown. Immediately after the fuse blew, I checked voltage on the battery and it read 12.9 volts (I don't think to check before I started the tractor). Right now, about an hour later, it reads 12.78 volts. So, I'm assuming the fact that the fuse blew immediately upon starting the tractor, without the PTO connected, means the PTO likely isn't the problem. Could it overcharge quickly enough to immediately blow a fuse, it is something else going on? Also, can you tell me what the pay is in this picture? Is it a voltage regulator? Thanks again for your help.
Jasonhttp://KH-25-755-03 KIT-REGULATO

Not sure what I'm doing wrong. I'm trying to post a picture from Amazon photos

https://www.amazon.com/photos/shared...YXElxgYmuPktB-

If you eliminated the PTO and still encounter blown fuse, you likely got a short somewhere. Time to break out the meter and start tracing the short starting from the fuse that's blowing. I would be looking for continuity to ground with the fuse out. The key switch could be the culprit, but keep in mind that the key switch grounds the magneto at "off". I doubt the lights could be the problem since it has it's own fuse.

Thank you for your response. I have to admit my knowledge of electrical is limited. How would I check for continuity to ground?

The owners manual says it only has one fuse but the schematic shows 2. The manual says it should be a 20 amp slow blow.

Looking at the pic of my 1872 (same tractor) I only see one fuse in the dash tower.

I would look real close at your headlight wiring for any shorted wires. This can be a problem area on the 82 series.

If no issues are found there I would do as other say and use a continuity meter and check for a short circuit.

I would remove the + terminal cable on the battery and place one lead on the cable you just removed, make sure your fuse is good and place the other lead of the meter on the battery negitave terminal. If your meter has a beeper I would turn that on. Now, turn the key to the "lights on position" and see if your meter is beeping. You will read resistance of you lights in this position but if it is 0 you have a short. Turn the key to the run position and start moving wires around and see if your meter starts beeping showing that you have a short.

Good luck and let us know what you find.

Thank you. Yes, I only found the one fuse in the tower. I bought 20amp show blow fuses. Thanks for the heads up on the lights. I'll check that out.

FWIW:
High amperage draw, or over current is what will cause a fuse to "blow"
High voltage has nothing to do with high current draw.
Amperage and voltage are apples to oranges comparison.
you have too high a current draw for the rating of the fuse.
find the short to ground or component that is drawing to much current/amperage.

There is a guy on ebay that maybe can rebuild your old PTO. Yours probably has a 1 1/4" crankshaft so it will be hard to find a replacement.

He just let me know he has one.

https://www.ebay.com/itm/363515201643

For another 90.00 you can buy a new one...
https://www.ihccw.com/index.php?rout...ge=2&limit=100

Thanks for the information on the PTO...very pricey. That's more than 1/2 what I paid for tractor, wheel weights, chains, 60 inch Haban Deck and Power Angle snow blade 4 years ago!
I did check for continuity with the battery unplugged as suggested by Oak. When I turned on the lights, my meter beeped. When I turned it to on, it also beeped constantly, regardless of which of the wires I moved around. As an aside, my started had sounded like it was grinding a bit over the past several months. My son and I had previously taken all of the heat shrouds off to find that the nuts had come off entirely and the starter was just sitting on the studs. We tightened it up as best as I was able, and put a jam nut on to try and keep it tight, but admittedly, the tools I have didn't do a great job of getting into the small space to really crank it tight. I say this, because when I tried to start it today, it really sound like it was grinding a TON and bogging down, and I saw sparks coming out from under the heat shroud. When I reached underneath to the starter, I could wiggle it by hand. Looks like I will need to get in there again. Could it possibly be something with the starter causing it to short? I appreciate your help. I am getting frustrated as electrical isn't my specialty. I am reaching the point I might just take it to someone, but I have a son in college and my free money is going there. My wife wouldn't be too pleased with me paying someone hundreds of dollars to fix this old tractor.

Some say you can service the starter with the in the tractor. I found it is much easier to lift the engine to service it. It takes a less time to pull the engine than you think.

I could be wrong, but I doubt your starter is causing the fuse to blow. When you are out there putting th 2072 to work, the fuse blows during run cycle. That's when your PTO goes out because it loses power after fuse blows. Tractor can still run because it has magneto and does not need power. The starter is inactive since the machine is running and you are not in start cycle.

In summary, IMO,.... the loose starter is a separate and different issue and is probably not connected to blowing the fuse. The starter, by itself, is not directly connected thru the fuse but the solenoid which activates the starter is connected thru this fuse

When you get your starter fixed.... since you stated you aren't electrically inclined, I wonder if the fuse blow if you NOT use the PTO and/or the lights? If fuse still blows without the use of PTO and lights, you could could eliminate those two possible culprits if not completely.

To track down a short, wire a head light bulb in place of the fuse. When the short is located, the bulb will light. Fix the short with no blown fuses.

Thank you to everyone who posted with helpful hints and technical support. After going through the wiring for just about the entire tractor, I lifted the seat only to find a 1-in section of insulation rubbed off of the positive battery cable. Fixed that, pulled the motor and tightened up the starter, and now everything works as it should. Again thanks everyone for all of your help, I really do appreciate it