Motor Shutting Off

[jfhunter64]

Hello All,

First time posting here, so I will try to get as many details as I can while trying to be brief.

I have a Simplicity Broadmoor bought ~6/2020 , Model 2691673-00, mfg date 12/12/19. 48" deck, Briggs and Stratton 25.0 HP/ 724cc model 44S9770047G1

Regardless of whether I am mowing or using the mower to just haul with my wagon, the motor will shut off after about 20-30 minutes. After the initial shut down, the time to shut off gets exponentially shorter- about 5 min, then 1 min, 30 sec, (all rough guestimates, I did not actually time them) then it won't turn on until I let it sit for a few minutes. Even after sitting, for about 30 minutes, it will shut down like before. I need to let it sit overnight before I get another 30ish minutes out of it.

I noticed the circuit breaker tripping, so I got a (used) replacement from my neighbor who happens to have had the same style, voltage, and amperage trip. The new breaker worked for one (1) cut, about 1.5 hrs. At the next cut it shutting down again after about 30 minutes. Seconds before it starts to shut down, the power steering starts to give out. This happened with the old breaker too.

The battery is brand new, I thought maybe it was going bad and the power steering was just the first thing to give out.

I don't mind getting a new breaker at about $15, but I don't want to keep replacing parts until I find the problem. Any tips or good videos on how to test what is tripping the breaker? Could it be just that both breakers are bad? I don't mind taking a multimeter and putting in some time to figure out what going on. The local dealer is not very helpful and charges for everything thing (has even tried to charge me for warranty work).

Thank you all in advanced. I hope I gave enough information. I would be happy to ask any questions to help get to a fix.

-John

 

[Rivets]

Sounds to me that you have a circuit on the unit creating a high resistance, causing the circuit breaker to trip. This can be caused by many things, dirty or bad grounds, wires corroding, switches corroding, wires intermittently opening or shorting, etc. This type of electrical troubleshooting is one where a technician needs experience and patience to solve. If it came to me with this problem, I would start by checking every connection I could find, making sure each one was clean, dry and tight. Next I would run the unit until the problem occurred and then use my nose and fingers to find wires or components which are hot and overheating. Tools I would have on hand. A assistant, wire brush, small file, spray contact cleaner, air supply, dialectic grease, and a truck load of patience. I used to run into a problem like this about once a year, when I was working full time, and have had to bill customers anywhere from thirty minutes to (YES) eight hours. I’ve attached the parts manual which contains a schematic for your unit which should help you in your adventure. Good Luck and post back if you have any questions. If you don’t feel comfortable tacking this job, I recommend finding the oldest mechanic in your area, who understands your problem, may have to get out of your local. The younger guys most often only understand basic repairs or plug and play systems. https://www.thepowerportal.com/ipls/ipl.htm?md=2691673-00~_IPLURL_LO.pdf

 

[jfhunter64]

Sounds to me that you have a circuit on the unit creating a high resistance, causing the circuit breaker to trip. This can be caused by many things, dirty or bad grounds, wires corroding, switches corroding, wires intermittently opening or shorting, etc. This type of electrical troubleshooting is one where a technician needs experience and patience to solve. If it came to me with this problem, I would start by checking every connection I could find, making sure each one was clean, dry and tight. Next I would run the unit until the problem occurred and then use my nose and fingers to find wires or components which are hot and overheating. Tools I would have on hand. A assistant, wire brush, small file, spray contact cleaner, air supply, dialectic grease, and a truck load of patience. I used to run into a problem like this about once a year, when I was working full time, and have had to bill customers anywhere from thirty minutes to (YES) eight hours. I’ve attached the parts manual which contains a schematic for your unit which should help you in your adventure. Good Luck and post back if you have any questions. If you don’t feel comfortable tacking this job, I recommend finding the oldest mechanic in your area, who understands your problem, may have to get out of your local. The younger guys most often only understand basic repairs or plug and play systems. https://www.thepowerportal.com/ipls/ipl.htm?md=2691673-00~_IPLURL_LO.pdf

Thank you for your input. So I've spent about 3 hours in the garage cleaning any harness i can find. There are only a 2 or 3 that I can not get too.

As I'm doing this, I ran the engine for about 45 minutes at low speed- kept running (did not replicate issues). I bumped up the throttle to mowing speed and sit for 25 minutes- still ran. It was not until I started moving that the engine cut off after about 30 seconds (just enough time to get out of the garage and maneuver around the wife's car). So not sure where that leads me. In my limited knowledge, I feel like then transmission is putting a strain on the engine and somehow the alternator is pushing out too much amperage. That doesn't sound quite right to me, but I'm grasping at strings at this point.

I may have to find a local repair shop. This mower is only on its third season and it has cost me so much heartache. I just can't swing a replacement.

 

[Rivets]

Two things I would do right now. Buy an inline spark tester. Install it and run the unit, watching it closely until it stalls. We want to see it you have a bad coil, either hot shot or hot open, causing the problem. If you loose spark your problem is most likely a bad coil. While you are waiting for it to stall talking a voltage reading across the battery. If the charging system is working properly you should get a reading of 13.2-14 VDC.

 

[jfhunter64]

Two things I would do right now. Buy an inline spark tester. Install it and run the unit, watching it closely until it stalls. We want to see it you have a bad coil, either hot shot or hot open, causing the problem. If you loose spark your problem is most likely a bad coil. While you are waiting for it to stall talking a voltage reading across the battery. If the charging system is working properly you should get a reading of 13.2-14 VDC.

I can't tell you how much I appreciate the quick response. Just ordered the a pack of 2 inline spark testers. I did check battery voltage and it was just over 14 VDC. I had 14.95 VDC from the harness that goes to the various engine components.

 

[volt]

I had somewhat simar problem. I found that the 'fuel shut off valve' was clogged. It will let some fuel seep out but not enough to keep running with load. That may be reason it will run until load is on, then dies. After waiting a while more fuel seeps out and it runs normally for a while again.