Small Engines (Lawn Mowers, etc.): Toro Wheel Horse problem, negative battery cable, gas leaks

Question
QUESTION: Hi there,

I recently acquired a 1994 Toro Wheel Horse 266H, model number 72083.
it ran fine at first,but sometimes needed jump started.  It then developed a fault where it would break PTO switches.  I replaced the switch twice, but now have installed a generic switch which has been fine.

It then failed to start after running the machine and the voltage was low on the battery so I replaced the battery which seemed to be the otriginal one.  the problem is still there.  After running for half an hour,if I stop and start again the starter clicks but the kohler engine wont turn over.  It will then often start after 30 mins wait.  I wondered if the battery wasn't charging but the voltage rises above 13v across the battery with the engine running.  Have you any idea what's going on?

Many thanks in advance,

Pete.

ANSWER: It sounds like you have an electrical short- or an electrical draw  in your wiring system.  In a poorly lit area (like your garage) remove the NEGATIVE battery cable.  Do you see sparks?  IF you do you have a drain that is constantly taking power from your battery.

start hooking and unhooking wires from safety switches, grounds, etc and then recheck the (sparks)  cable every time, you should be able to isolate it this way.  

It may also be a shorted wire that is located under your flywheel which is a bad alternator.  This is the most common area i have seen problems like this arise.

Good Luck, dont get frustrated, Electrical problems can drive one crazy, but if you troubleshoot it systematically you can find the root cause.



PLEASE make sure that there are no gas leaks or gas fumes prior to conducting this test

---------- FOLLOW-UP ----------

QUESTION: Hi David, thanks for your quick reply.

So I tried removing the negative battery cable (with the ignition on but engine not running) and there was a spark when I touched the cable against the battery terminal. I immediately tried the PTO switch, and got a result.  With the PTO off (blade not activated)there was no spark.  With the switch on, there was spark.  I tested the battery voltage before doing any of this and the voltage was 11.9v. With the switch on I tested the voltage and it was falling rapidly, by a volt every 5 seconds or so. I tested it after having had the PTO switch on, and the voltage  was 11.4v accross the battery.

Now this raises a few points in my head (bearing in mind I know very little about electronics!)

Is the problem of power being drawn from the battery a result of me fitting a generic switch to act as the PTO switch?  I used 5 amp rated wire and a 16 amp max switch. link - http://i275.photobucket.com/albums/jj310/PRGoudie/IMG_0076.jpg

Is there a problem in the wiring which controls the blade on/off?

Is there a problem at the blade end?  I believe it has an electric clutch?

Or is it just that the PTO switch swhould not be on at all without the engine running so the battery discharges, whereas with the
engine running it would charge to counteract this?

I am unsure whether the discharging battery power issue existed before I placed the generic switch, but there was definately the problem where the PTO switches were breaking/melting.

I would agree with you that a fault like this can drive you mad!  I spent a fair bit of cash getting it serviced and preferably don't want to splash out more with the risk that it never really works.  I would like to make the toro work without fault but if it's a case of having to charge it or remembering not to turn off/on after running
I can live with this as long as the problem is not dangerous.  
I look forward to your thoughts!

Thanks in advance,

Pete.

ANSWER: Pete,  This is one that makes us scratch our heads

With the ignition in the OFF position, Engine not running, remove the negative cable?  Do you have a spark?  Keep the ignition in the off position throughout this test.  ALSO unplug the keyswitch from the wire harness and do the test...sometime key switches short out and cause all kinds of problems.  Wouldnt it be great if this was the problem!  So simple!

If you do we need to isolate the component that is causing the battery draw

Disconnect the blade switch retry the negative cable test again, spark?  this is your problem area

If no spark when the switch is disconnected reconnect the switch and go to the next item in the wiring harness, the electric clutch, do u have spark now?  Yes, this is the problem area, NO... reconnect the wires and follow the circuit to the safety switches on the seat, clutch etc...

Systematically do this until you isolate your problem. Including disconnection the wires from the engine, regulator, harness, etc

I think from what you tell me however is that you have a voltage regulator or alternator  problem.

I would definitely replace the PTO switch with an original Toro switch to rule out the switch as a problem while troubleshooting.

hang in there, keep me posted... well get it figured out...

---------- FOLLOW-UP ----------

QUESTION: Thanks again.

It's late here in Scotland so I will do further tests in the morning.
I can answer some of the things you have come back to me with.

There is no spark with the key in off position.  There is no spark with the key in on position but PTO switch disconnected.  There is spark with the key on and PTO switch on. ???

The problem is I have gone through 3 toro switches which cost me around $40 to get to the UK.  I installed the generic switch to allow me to keep cutting the grass, although it is hardly growing now that it is winter which gives me some time to try and figure this thing out!

Thanks again

Pete.

Answer
Pete:

Based on this information, I would be looking at the electric clutch unit.  Now you said that the prices of the switch shocked you.... WAIT until you see see the price of the clutch.  Clutches usually work or the dont..

So focus on the clutch troubleshooting.  

Hey got an extra bed...id love to come to Scotland and help fix this problem