Electrical Issue

[woodlandfarms]

So, things are suddenly going south on the PT. And in an area that I think PT has failed miserably in, which is electrical.

My system is protected by one circuit breaker, making identification of a failing system impossible in my opinion to track down.

I just cleaned my ground terminals, and found a short in a seat wiring, but what is happening is randomly the engine is shutting down, and in doing so it is blowing the breaker. What is weird is that the engine starts to conk out, then comes back, conks again then dies with the breaker popping at that moment. I don't know if there is a thermal disconnect on the breaker (meaning it momentarily opens thus starting to stall the engine, cools and reconnects then the engine winds back up then dies again, popping the breaker).

Any thoughts on how to trouble shoot an intermittent electric with only one breaker?

 

[MossRoad]

Unfortunately, you would have to disconnect all electrical systems and then hook them back up one-by-one until you find the one that is causing the problem. Bummer.

 

[BobRip]

You could disconnect one half the loads and see if you still have a problem. It the problem persist at that point then it is in the loads you left connected. Then disconnect one half the remaining loads and see what happens. This enables you to resolve the problem much quicker than one item at a time. This is called the split half technique. If this is not clear I can elaborate a little more, but you probably get the idea.

 

[ponytug]

If the engine is conking out, then the fuel solenoid is cycling. That could be happening because you are drawing all the power down before tripping the breaker, or because something is worn in the cable to the solenoid. Have you tried cleaning the contacts on the engine interconnect? The one that must be disconnected when bleeding the air out of the main hydraulic filter?

If I were you, I would give the cables a once over, especially the ones behind the dash and at the main electrical box. I would also consider that grounding might be an issue (battery, engine, front to rear). I put in extra grounds from the dash and the engine/battery to a single point on the rear tub, just to keep from having to run down weird grounding issues later.

My PT has a 14(?) wire custom cable running the dash to the main electrical box. If you are getting too much grief, I'd replace the whole thing and be done with it. My memory is that I found a second source besides PT, by getting to the right wire number and guessing on the the wire gauges. It sounds like you have a lot of wear in the tunnel.

Good luck! I hate running down intermittent issues.

All the best,

Peter

So, things are suddenly going south on the PT. And in an area that I think PT has failed miserably in, which is electrical.

My system is protected by one circuit breaker, making identification of a failing system impossible in my opinion to track down.

I just cleaned my ground terminals, and found a short in a seat wiring, but what is happening is randomly the engine is shutting down, and in doing so it is blowing the breaker. What is weird is that the engine starts to conk out, then comes back, conks again then dies with the breaker popping at that moment. I don't know if there is a thermal disconnect on the breaker (meaning it momentarily opens thus starting to stall the engine, cools and reconnects then the engine winds back up then dies again, popping the breaker).

Any thoughts on how to trouble shoot an intermittent electric with only one breaker?

 

[woodlandfarms]

Well, thought i had it all handled. First I cleaned all wires up, looked at all the connections. I pulled the ground on the battery side and cleaned it. Just then My wifes uncle stopped by, nice guy, ran a pulpmill since he was a kid and knows mechanics inside and out. Anyway, he quickly isolated the PTO wire saying it looked like it had rubbed down and was making contact. He threw some tape around it and all was good with the world.

I have been mowing since 2PM and it just conked out again (4 hours of hard mowing). Of course it left me in a bad way and I had to walk out. Conked out the same way again.

Oh so darn frustrated.

Never have had electrical issues with the PT. I now the electrical system is basically a very bad design but did not see this as happening.

 

[CobyRupert]

So, things are suddenly going south on the PT. And in an area that I think PT has failed miserably in, which is electrical.

My system is protected by one circuit breaker, making identification of a failing system impossible in my opinion to track down.

I just cleaned my ground terminals, and found a short in a seat wiring, but what is happening is randomly the engine is shutting down, and in doing so it is blowing the breaker. What is weird is that the engine starts to conk out, then comes back, conks again then dies with the breaker popping at that moment. I don't know if there is a thermal disconnect on the breaker (meaning it momentarily opens thus starting to stall the engine, cools and reconnects then the engine winds back up then dies again, popping the breaker).

Any thoughts on how to trouble shoot an intermittent electric with only one breaker?

Sounds like it's shorting to ground (frame), drawing off current (and voltage) to the fuel solenoid. Maybe it cuts in and out when the wires are vibrating (shorting, not shorting), but if it shorts for too long ( basically in a short there's no resistance between the +12V terminal and the -neg terminal/frame), thus a large short current, so the fuse blows.
Check that there's enough tape (more than 1 layer) where wires were "fixed" on switch. Looking for sparks is easier in the dark.

 

[MossRoad]

You could disconnect one half the loads and see if you still have a problem. It the problem persist at that point then it is in the loads you left connected. Then disconnect one half the remaining loads and see what happens. This enables you to resolve the problem much quicker than one item at a time. This is called the split half technique. If this is not clear I can elaborate a little more, but you probably get the idea.

That's a very good suggestion. Just keep dividing the potential problem points in half.

 

[Coyote machine]

The other possibility is the breaker itself is faulty. Is it anything special, or just a standard automotive type that could be easily replaced? Another thing to do while working on the wires that come close to frame members is to put them into loom so there is less/no chance of shorting to the frame.
Can you get us some pics of the general mess of wires so those not familiar with the machine can think on it some?
What age /condition is the battery in? The age of the machine/# of hours on same. Condition of ignition switch, starter, alternator, etc. Any gauges like volt/amps/ etc.?

 

[ponytug]

Carl- Sorry to hear about the walk out. That's got to be frustrating. If the battery is old, it is not out of the question for the post or one of the cell connectors internally to have fractured, especially given the sort of use that I suspect you have put it through. If you have already cleaned, and check the main + & - leads off the battery, and the battery is old, I would consider it. It is easier and cheaper than replacing the main wire bundle.

I agree with Coyote Machine that it isn't out of the question for the breaker to die, but I don't know how to prioritize it against everything else going on.

All the best,

Peter

 

[Coyote machine]

Carl- Sorry to hear about the walk out. That's got to be frustrating. If the battery is old, it is not out of the question for the post or one of the cell connectors internally to have fractured, especially given the sort of use that I suspect you have put it through. If you have already cleaned, and check the main + & - leads off the battery, and the battery is old, I would consider it. It is easier and cheaper than replacing the main wire bundle.

I agree with Coyote Machine that it isn't out of the question for the breaker to die, but I don't know how to prioritize it against everything else going on.

All the best,

Peter

I'm throwing the breaker into the equation so it doesn't become overlooked when it's right in front of one's face, so to speak. And because it is the only breaker keeping the entire harness from frying extra crispy it is more prone to failure than if there were multiple breakers protecting various circuits; wow, what a concept- multiple breakers! Gotta throw some levity into frustrating situations to lighten things up and put them into perspective. Look at it this way, OP, when you're done, you'll have a better, more reliable machine going forward.
In addition to the battery being a possible piece of toast, you should try moving the ground cable with rubber glove on, to see if anything happens while the machine is running with lights on, etc. Sometimes corrosion is hidden inside the actual cable and it can no longer handle the current passing through. Make the battery post and their respective connectors shiny metal clean and tight. Check each cell with a specific gravity syringe tool, and if questionable remove it and get it load tested at your local Autozone or equivalent store. Failure of load test is time for a new Interstate battery sized to your machine. Always a good idea to start at the battery and work out to wherever the problem leads. Take a close look at the ignition switch, connections to starter, etc. to be sure there is no evidence of corrosion at the cable ends or especially inside the sheathing of the bigger wires to the starter, etc. Is there any type of fuse box in addition to the single breaker or is that the last and only line of defense?