Ariens EZR 1742 Motor Dies When PTO Engaged

[jc4569]

The Problem:
When I engage the PTO switch the engine dies.

What I have changed:
I had this mower given to me free from a relative. I rewired the mower due to some of the wires having had a rodent problem. I replaced the key switch and PTO switch. The neutral safety switches where bypassed because they were faulty.

What I know:
I had the mower running after the rewiring and switch replacements.
Now I can start the mower and drive with no issues.
The mower cut grass within the last week.
When sitting on the seat and the key in the on position - When I engage the PTO switch, I can hear the clutch click.
I have tested the seat switch, brake switch, PTO switch, and the key switch with a volt meter and all positions are working at the terminals of all switches, based on the switch guide within the repair manual
I have may have wires in the wrong position
The belt and pulleys turn when manually turning them from the main pulley to the mower deck pulley.
The motor dies quick when the PTO is engaged. There is a little movement on the mower deck but it doesn't seem like it is too stressed to engage.

Any suggestions are appreciated.

 

[Rivets]

I would start by rechecking each of the safety switches, particularly the seat safety switch. Some of them are normally open and some are normally closed. These type of problems will test your patience, so take your time and go slow. You might find the problem in tem minutes or it could take hours. Remember the #1 rule in working on electrical problems. DON'T ASSUME ANYTHING AND VERIFY EVERYTHING. Having both a test light and VOM will be your best tools.

 

[EngineMan]

Am with Rivets on this one, you should also replace the switch's that you bypassed.

 

[jc4569]

How else should I be testing the seat switch other than with a continuity test through a volt meter?

Will the amount of voltage going to the clutch when engaged cause any issue with the draw of power from other components?

If I bypass they seat switch, will it tell me anything?

The other step I am going to try tonight is unplugging the clutch wires at the clutch and engaging the PTO and see if the same issue occurs. Not sure if that will pin point any issues with the clutch or the relay?

Thanks
I'll keep my progress posted, hopefully it will help the next guy.

 

[EngineMan]

Check the start relay, magneto kill goes to pin 87a and there should not be a path to earth (ground) pin 30 when you are trying to start the engine.
(power to the solenoid) check both left and right neutral switches make sure they are closed, check for continuity at pin 3 and 9 PTO switch and at S1 and S2 on key switch, red/violet at S2 and brown from S1 to solenoid. At S2 you should have battery volts when the key is turned to start and also at coil 1 on the solenoid. You can leave the seat switch open (no path to ground). If all the above is correct you should be able to start the engine.

 

[Rivets]

Am with EngineMan on his last post. See if you can view this diagram, which might help.

Diagrams

 

[EngineMan]

Yes that is the wiring diagram am working with...!

 

[jc4569]

I solved the problem.

The brake switch was not allowing full voltage to pass through. When I tested it for continuity originally it passed, so I continued on. But as I proceeded everything brought me back to that switch. So I pulled it and tested further and realized it went from 12 to less than 3 volts, very internment. The brake switch was carrying the voltage load for the Fuel Solenoid, when the PTO is engaged.

If you follow the diagram, the power is coming off position A on the key over the "Purple" wire into the PTO switch (When Disengaged is transferring from 3 to 9) and servicing the power through the "Start Relay" to the Fuel Solenoid. When the PTO is engaged the link from 3 to 9 is broken and the power is then being serviced from "red/Yellow" wire off the Seat/PTO relay. When the Brake Switch was not working the power to the Fuel Solenoid was cut, causing the motor to stop.

Long story short, don't assume, double check.

What helped me the most was printing out the wiring diagram and going from point to point testing, I then marked out the wires I tested or knew worked, it made the diagram a little less overwhelming, eliminating one section at a time.


Thanks for all the replies.

 

[EngineMan]

Main thing is you got there, like you say always double check.....thanks for the update.:thumbsup:

 

[Rivets]

I wish more posters would read what you said about electrical problems. ASSUME NOTHING, VERIFY EVERYTHING.