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Discussion Starter #1
Looking for ideas. Bought my Conquest in 2005. Developed problem suddenly this week. Engine starts tractor moves but when you engage blade (PTO switch) the engine dies. Suspect it might be an issue with one of the safety switches....or possibly the PTO clutch. Anybody had any similar problems? Any ideas on what to check?
 

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Welcome to the forum Tim! :)

First switch and circuit I would look at is the mow in reverse cutout. Probably a switch right next to the tranny with two wires coming out of it. It should be activated when you put the tractor in reverse by the linkage going from the pedals to the transmission. If only two wires that would indicate the switch is simply either normally open (no connection between the two wires) or normally closed (short between the wires). Normally in this case would mean while driving forward.

A VoltOhmMeter or even a basic continuity tester will help you track down the problem a lot faster.
 

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Discussion Starter #4
Thanks Mark....called my dealer this afternoon and he told me to move the RMO (reverse cutout over ride) then try to engage the PTO. Normally you would engage the RMO only after engaging the PTO. I tried this and he was correct ......if I move the RMO switch and then engaged the PTO the engine did not stop. Solution according to dealer is changing the the RMO....he is sending one in the mail to me. So your guess is correct.....well hopefully.....guess I'll have to wait till I install the new RMO switch
 

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Good deal Tim! Sounds like your on the correct path or at the very least found the area to dig around in. :cool:

But like you say, until it's fixed you never really know for sure especially with electrical issues. Sure helps though being a constant issue rather then an intermittent. :D
 

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Discussion Starter #6
Update.....changing the RMO switch did not solve the problem. Good news is that I think I can actually mow by engaging the RMO before engaging the PTO. To me that indicates that the sensor that indicates the mower is in reverse has failed. As a result anytime the PTO is engaged the mower thinks its in reverse and the engine dies. Thats the only explanation I can think of why activating the RMO first prevents the engine from being killed by engaging the PTO......Anyone know where the switch/sensor is for the reverse peddle.....tried to follow wired but coudln't easily see any wires near reverse peddel......I wonder if it is near the transmission ? Wish I had a wiring diagram
 

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Discussion Starter #7 (Edited)
crawled under the mower one more time and found the reverse switch...its very well hidden. Its on top of a support plate for the pedals. Its a plunger type switch that is pushed in when the reserse pedal is pushed down to go in reverse.
Found another web site where someone said they had to adjust the plunger swited to badk it off a little ....doesn't look adjustable to me.....looks like two hes head screws hold the plastic switch to the top of the plate doesn't look like there are slots to adjust it.
 

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Maybe the adjustment is in the linkage itself where it connects to the transmission?

Other then moving the switch the only other possibility I can think of would be if the plunger itself can somehow be turned to make adjustments. But I would guess that to be unlikely.

Anyway to as a test pull the reverse pedal up slightly to see if that extra pedal travel deactivates the switch from reverse mode?
 

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Discussion Starter #9
Ended up loosening the two hex screws to the reverse pedal plunger switch and there was some adjustment ....moved it back at retightned it....problem solved. Turns out that the plunger switch position is what was causing the problem all along. Why this suddenly developed is beyond me.....switch mount screws were very tight. Hard to figure out how it could have become out of adjustment.
Still have to figure out why I have to jump start engine......battery again? or something in charging system. When I fixed switch when I turned on headlights or engaged PTO my battery warning light came on.....when I turned headlights off and PTO waited about 10 seconds the warning light went back off.
Hopefully just the battery....but its less than a year old
 

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Glad to hear you resolved the switch problem. Maybe it was adjusted a little too close to the cutout position all along then add in some wear over time of the linkage..... :confused:

Maybe you'll get really lucky and cleaning the battery terminals will solve the voltage problem. ;)


So have you discovered problem number three yet? Problems come in three's ya know. :rolleyes: :D
 

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Discussion Starter #11
maybe your right about the switch being originally marginal and then with a little wear it suddenly became a problem....probably won't do and more trouble sHooting on the battery issue till Thursday.....have that day off .....and I really hope your wrong about trouble comes in threes . One thing for sure is your really don't get to know your tractor until you start working on it
 

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Discussion Starter #12
Well charged the battery and everything works great. Mowed Grass Thursday afternoon and everything works fine......However....I do think I have a problem.....put the multimeter on the battery while it was running and only got 12.4 V ....teste before and after mowing with the motor at full throttle......From what I have read the voltage should be around 13.4 or so if it is charging properly. Any ideas ? And good procedures for trouble shooting what could be wrong ?.....I really am not familiar with how the charging systems work on lawn tractors....The negine is a 20hp Vangard B&S
 

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12.4V does seem low. Most likely just a bad fuse or fusible link coming off the coil on the engine flywheel. Bad Rectifiers (diodes) or if used a regulator are other possibilities. I think it is kind of rare for the coil itself to fail on them. Might of had a shorted cell in your old battery that caused further issues.

Here's a document from Briggs that might prove useful:

http://www4.briggsandstratton.com/miscpdfs/RNT/alternator_replacement.pdf
 

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Man, that's a great resource for testing electrical circuits. I'll make a sticky of that so it's available to all in the future. Good luck on your system. Might be something as simple as a dirty connection. Keep us informed.
 

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Discussion Starter #15
WOW ....Mark this is just what I needed....don't have any expereince with electrical issues on small engines .....this should help me to know what I'm looking at...and give me some things to try. I was suprised the battery took a charge when I hooked it to my charger...thought it had a bad cell....but it charged to 12.8 V and I took a reading during the engine starting and it dropped to maybe 9.5-10.5 V while engine was cranking. Those are pretty normal readings....I think ? .....I'll use this guide and see what I can find out....thanks again
 

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Discussion Starter #16
Had some multimeter fun this morning ......think I found the charging issue....using Marks reference and an internet article on trouble shooting ....I had enough info to start isolating the porblem........unplugged the lead from the stator(coming out of engine) to the regulator......even just unplugging this lead was a good indication that I had found the problem the regulator side of the connector was black and charred....definately been hot at one time....... I then checked the AC voltage coming from the strator about 31 Volts AC......I then reconnected the connector and checked the DC voltage coming from the regulator.....It only read about 3 or four volts DC.....believe it should read at least 14 volts to be sending out a charge to maintain the battery. So I am assuming that the regulator is bad. Think I will go order one today. Battery started the engine again just fine this morning ....I wonder how many starts a battery can provide without getting charged ? I' am guessing I have had this issue for a while.
 

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.....even just unplugging this lead was a good indication that I had found the problem the regulator side of the connector was black and charred....definitely been hot at one time......
Yep, that could be a sign of a problem. :D

When you swap out the regulator be sure that connection that has been hot is making a good tight connection on the new terminal. Might even be best to replace that connector if possible. After being hot they can loose their spring tension and not grab tightly. It might have loosened up over time becoming resistive which creates heat and might have caused failure of the regulator.

Many years ago I owned a 78 Jeep Wagoneer. One day in town thankfully close to home, raining, lights, defroster fan and wipers on I noticed some light smoke start sifting up from the instrument cluster. :eek: I started turning everything off. Smoke stopped coming out. Figured ok, must be one of the switches going bad.
Stopped at a light and using the turn signal and brake smoke started coming out again. :eek: Seemed whenever I used lights even when only w/brake and turn signal was when it started. So I slowly made my may back home using as little electric has possible. I pulled out the instrument cluster and found a black melted wire and terminal on one of the gauges. Rather then using a voltmeter the Jeep used an ammeter. One of the nuts had loosed up on the terminals. So I tightened the terminal nuts back up, wrapped some electrical tape around the melted insulation as the wire was still ok. I turned everything on that drew electric and no more smoke. :cool:
 

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Discussion Starter #18 (Edited)
Luckily it it the connector that is on the regulator side that was damaged......according to the parts manual the connector will be part of the new regulator. I suppose there is a possiblity that the issue was just the connector and the regulator is OK.....but thought I'd just replace the whole regulator since the connector and four inch wire harness comes with it. NOT CHEAP THOUGH....about 60 bucks. Scary story about your Jeep.
Might wrap a little electical tape around the connector to make sure it stays tight to be on the safe side. Thanks for your help, Mark.
 

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...according to the parts manual the connector will be part of the new regulator. .....
Ahh, since they include that connector makes me wonder if that was something they found to be a common failure along with the regulator. ;)
 

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Discussion Starter #20
Well replaced the regulator and that did fix the problem. Easy job too.....ordered part from Briggs., part came in two days, loosen two screws, pu tnew regulator on and tighten the two screws and plug in the connector to the strator and plug in the DC output connector the the wiring harness. Only thing that threw me a little is after I replaced the regulator, I checked the DC output voltage and it was only about 3.5 volts......so I thought I had something else wrong. But after doing some research online I noticed that checking the AC strator voltage (input to regulator) was a common check ....BUT instead of checking the regulator DC voltage output....all the references checked the DC amperage output. Since this was a 16 amp system I was a little afraid to check this with my multimeter directly and I didn't have a shunt so I decided to check the battery voltage befors starting engine (12.19 V) and then check if after I started engine to see if it was charging. I started the engine and check voltage and it was 14.15 V. So I am declaring victory and calling this job done.
 
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