My Twin 46 won't start

mshearne

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I have been given a Murray lawn tractor - model 46102X6B. I have been using it for a while, but now it won't start. Feels like it may be a safety switch problem. I have replaced the solenoid last year. There is 12V on the battery side of the solenoid until I turn the switch to start, then no voltages on any of the posts of the solenoid. If I connect the battery directly to the motor side of the solenoid, then the starter engages.
How can I tell which switch is not working (assuming it is a switch problem), and get a new one?
Thank you,
Matt
 

bertsmobile1

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The battery side heavy terminal should always show 12V except when actually cranking the engine when a drop as low as 10V is the limit to acceptable.
If you get 12,5 V one minute and 0 V the next on the feed wire then your terminals are dirty, loose or corroded or your battery is deceased.

Run a pair of jumper leads directly from the battery to the starter motor.
If the starter spins the battery is fine & starter is fine.

Now leave the negative wire attached to the motor and try to crank the engine
Engine spinns up then the earth on the mower is bad.

Put the jumper on the battery side of the solenoid and try to crank the engine.
Engine starts then the power wire from the battery is the culprit.

No difference then move the jumper to the engine side of the solenoid.
No joy then the power feed to the starter is bad

Leave the jumper on the feed side of the solenoid and dridge ths terminal to the small trigger terminal on the solenoid.
No joy then the solenoid is bad

Works with the bridge but not the key then the fuse, key switch or a safety switch is bad.

Should keep you ammused for an hour or so.
 

mshearne

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Thank you for all the information. Sorry it took so long for me to reply.
I am sure that I have more than one problem now. The battery is low, and I have been using a charger to do the testing with. I should get a new battery and repeat the steps you have outlined. I also know that the motor is hard to turn over even when attached to a good battery. So, maybe a starter problem? Low voltages on the battery and I don't stand a chance of starting.
I connected the battery directly to the starter and it tried to start. Just turned over and over. New development. Tried again with safety switches engaged and battery was too drained to do anything. Try again later.
You mentioned that I may have a bad key switch. Haven't thought of that. There is a safety switch under the seat. How do I go about changing it our or bypassing it?
 

bertsmobile1

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Nearly all starter problems end up being valve lash so start by adjusing them.
Using the charger explains the 0 V reading as they have a safety cut out when overloaded.
The seat switch has nothing to do with starting the engine,
The switches that stop the motor cranking are attached to things that will place too much load on the starter.
So they are the PTO & Clutch switches,
 

mshearne

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Another thing I noticed yesterday; When I charged the battery and went to start the engine, it would just turn over and over and over....
But, it wouldn't start. Does this have anything to do with bypassing the starter solenoid? I have the battery hot terminal attached to the motor side of the solenoid and no where else.
 

BlazNT

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Another thing I noticed yesterday; When I charged the battery and went to start the engine, it would just turn over and over and over....
But, it wouldn't start. Does this have anything to do with bypassing the starter solenoid? I have the battery hot terminal attached to the motor side of the solenoid and no where else.

Starter solenoid does not start your mower it just supplies power to the starter.
 
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