Jump to content

Nominations for Tractor of the Month
Garden Tractors and Parts on eBay



Photo
* * * * * 1 votes

1971 120


  • Please log in to reply
607 replies to this topic

#571 Trav1s ONLINE  

Trav1s

    Got points?

  • Senior Member
  • Member No: 5472
  • 2,603 Thanks
  • 3,750 posts
  • Location: Cedar Rapids, IA

Posted June 18, 2015 - 04:20 PM

Got the voltage reg and the gauge still shows "discharge" when running.  I am wondering if I have the wiring backward to the ammeter.  The schematic does not really help me...

 

Also, does this piece need to ground?


Edited by Trav1s, June 18, 2015 - 04:22 PM.

  • larisaPn said thank you

#572 lyall ONLINE  

lyall

    Tractorholic

  • Senior Member
  • -GTt Supporter-
  • Contributor
  • Member No: 2180
  • 1,747 Thanks
  • 1,398 posts
  • Location: State Center, Iowa

Posted June 18, 2015 - 08:33 PM

see if you can trace your wiring

from the stator to the ammeter - should go on the left side of the ammeter ( looking at the front of the ammeter)

from the right side the wire should go to the switch

 

no the ammeter should not need a ground wire from it



#573 Trav1s ONLINE  

Trav1s

    Got points?

  • Senior Member
  • Member No: 5472
  • 2,603 Thanks
  • 3,750 posts
  • Location: Cedar Rapids, IA

Posted June 19, 2015 - 09:31 AM

What about stator/regulator - Does it need to ground?

 

I have traced the wiring to the ammeter and it looks correct from what I can tell.  It is possible a splice broke too as the harness has had some repairs.



#574 lyall ONLINE  

lyall

    Tractorholic

  • Senior Member
  • -GTt Supporter-
  • Contributor
  • Member No: 2180
  • 1,747 Thanks
  • 1,398 posts
  • Location: State Center, Iowa

Posted June 19, 2015 - 03:44 PM

the stator has 2 wires from it to the voltage regular,the out side two that connect to the voltage regular, then the center wire should go to the switch.

the voltage regular should not have to be grounded.



#575 Trav1s ONLINE  

Trav1s

    Got points?

  • Senior Member
  • Member No: 5472
  • 2,603 Thanks
  • 3,750 posts
  • Location: Cedar Rapids, IA

Posted June 19, 2015 - 06:23 PM

So here was today's work:

- replaced voltage reg/rectifier

- tested continuity on wires lyall suggested as well as a few others

- cleaned connections on ignition switch, main harness at engine, and rectifier

- cleaned battery terminals

 

and the results:

Pic 1 is WOT with new gauge. This is about where it ran before with the old gauge and has always ran in that range without problems.

 

Pic 2 is with the PTO engaged after all of my work. I am thinking the PTO clutch is drawing some SERIOUS amps and the engine cannot keep of with the PTO clutch demands.  All of this leads me to believe the PTO clutch is about ready to short out or is just going bad.  I have the clutch off of the 312 that I will likely swap in place after I figure out if it will work. 

 

Thank good the old Lawn Boy keeps going.

Attached Thumbnails

  • image2.JPG
  • image3.JPG


#576 lyall ONLINE  

lyall

    Tractorholic

  • Senior Member
  • -GTt Supporter-
  • Contributor
  • Member No: 2180
  • 1,747 Thanks
  • 1,398 posts
  • Location: State Center, Iowa

Posted June 19, 2015 - 10:27 PM

Travis

Have you check the electric PTO with an ohm meter?

 

Here are two file that should help you with an electric PTO

Attached File  Garden_Tractor_Clutch_Troubleshooting_and_Installation_Guide.pdf   195.76KB   10 downloads

 

Attached File  electricclutchtesting.pdf   57.04KB   9 downloads

 

If that does not help I would check the PTO switch,  it could be the problem.

 

 


  • KennyP said thank you

#577 Trav1s ONLINE  

Trav1s

    Got points?

  • Senior Member
  • Member No: 5472
  • 2,603 Thanks
  • 3,750 posts
  • Location: Cedar Rapids, IA

Posted June 20, 2015 - 01:03 PM

Today's findings...

 

I cleaned the PTO clutch connection good then did some simple testing.  I found the following with the clutch on the tractor:

- Same behavior if I go thru the tractor's electrical system or direct jumper from battery to clutch

- Voltage is OK but resistance is really wierd - both the analog and digital meters do not show resistance on the scale.  After Zeroing out the analog unit it goes all the way to the right indicating no resistance!?!  The new digital unit (zeroes itself out) and will not display anything. 

 

To confirm it is not my insanity figuring in this I grabbed the PTO clutch coil from the 312 and it does the same things with both meter.

 

I also ran to O'Reily's and grabbed a fuse for the original voltage reg and it does the same thing. 

 

So to recap the facts on the tractor from the rebuild

- original wiring harness is being used (it was repaired and done will before I got it)

- new ignition switch (from Napa) and PTO switch (from Deere) when reassembled in the summer of 2012

- tried new style voltage reg and one on tractor with same response

- AC voltage into regulator and DC out are OK

 

It will run for 20-30 minutes then stall due to no spark.  Charge the battery and it will run until the battery dies. 

 

I keep wondering if I am missing something....



#578 lyall ONLINE  

lyall

    Tractorholic

  • Senior Member
  • -GTt Supporter-
  • Contributor
  • Member No: 2180
  • 1,747 Thanks
  • 1,398 posts
  • Location: State Center, Iowa

Posted June 20, 2015 - 11:44 PM

My gut feeling it is the starter switch.

I think the starter switch  from NAPA is different from Deere.

try the switch from the 312.

check the back of the starter switches from both the 120 and 312.

Look for the stamped letters on the back of the switch, if the one from NAPA is different from the one on the 312 that would be the problem.

If they are some, then check the color of the wires that connect to the starter switch and the placement order they should be the same.

If not then you have to check the wiring harness over very carefully.



#579 Trav1s ONLINE  

Trav1s

    Got points?

  • Senior Member
  • Member No: 5472
  • 2,603 Thanks
  • 3,750 posts
  • Location: Cedar Rapids, IA

Posted June 21, 2015 - 07:40 AM

Just putting this info here for future reference:

 

JDparts lists 120 switch = AM32318

 

Jdparts lists 312 switch = AM103286 (SUB FOR AM32318)

 

I will try the 312 switch later and see if that makes a difference.  

 

 

Googled AM103286 and found this:

Stens 430-249 It crosses over to:


ARIENS 03115200
GRAVELY 019223
JACOBSEN 129746
JACOBSEN 129846
JOHN DEERE AM103286
JOHN DEERE AM32318
NATIONAL 1A808B
TORO 12-8140

The Stens 430-249 switch for a coil ignition is available at NAPA part number is 7-01854. I bought one today for $14.49.

 

Just to review some info on the tractor.  it was short or long blocked in the mid/late 90's with a Kohler blockI do not know which parts were swapped over to the new engine.  

 

Jdparts lists the following

- stator = AM32334

- voltage reg i= AM102596 (10-AMP) (USE WITH AM34734 CAPACITOR) (SUB FOR AM34733 AND AM32408)


Edited by Trav1s, June 21, 2015 - 07:58 AM.


#580 Trav1s ONLINE  

Trav1s

    Got points?

  • Senior Member
  • Member No: 5472
  • 2,603 Thanks
  • 3,750 posts
  • Location: Cedar Rapids, IA

Posted July 01, 2015 - 02:54 PM

So after talking with a guy at church he suggested checking the PTO clutch adjustment which was my next step anyway.  I think that the person who did the long block adapted a clutch and it has worn out of adjustment - and there is no adjustment in the assembly.  Going to try the 312 clutch on it and will go from there. 



#581 Trav1s ONLINE  

Trav1s

    Got points?

  • Senior Member
  • Member No: 5472
  • 2,603 Thanks
  • 3,750 posts
  • Location: Cedar Rapids, IA

Posted July 01, 2015 - 05:14 PM

Made some time this afternoon to look at the 120 and swapped the PTO clutch from the 312 over to the 120.  It looks like the clutch on the 120 was one adapted from another application and there was NO room for gap adjustment.  The PTO now sounds like it engages with more authority, the engines sounds to be under more load (need to adjust the governer), and the deck sounds more like what I would expect it to sound like.  

 

I am still left with a slight discharge at WOT with no load, and significant discharge with the PTO engages.  So my next list of items to do include cleaning grounds and possibly replacing the ignition switch.  

 

I will get some pics of the clutches up in a bit.



#582 Trav1s ONLINE  

Trav1s

    Got points?

  • Senior Member
  • Member No: 5472
  • 2,603 Thanks
  • 3,750 posts
  • Location: Cedar Rapids, IA

Posted July 01, 2015 - 05:26 PM

Old clutch vs new with old first

Attached Thumbnails

  • image.jpg
  • image.jpg
  • image.jpg
  • image.jpg

  • Navy Chief said thank you

#583 Trav1s ONLINE  

Trav1s

    Got points?

  • Senior Member
  • Member No: 5472
  • 2,603 Thanks
  • 3,750 posts
  • Location: Cedar Rapids, IA

Posted July 02, 2015 - 02:59 PM

Jumped from the voltage reg to the ground on the block and no difference.  I grabbed the rough Indak switch from the from the 312, cleaned it up, and installed it.  Nothing changed.  I believe it is coming down to the wiring harness...


Edited by Trav1s, July 02, 2015 - 03:44 PM.


#584 Trav1s ONLINE  

Trav1s

    Got points?

  • Senior Member
  • Member No: 5472
  • 2,603 Thanks
  • 3,750 posts
  • Location: Cedar Rapids, IA

Posted July 02, 2015 - 03:10 PM

 I think it is time to order a new ignition switch from the dealer - Might as well order 2 while I am at it as the 312 needs one too.  


Edited by Trav1s, July 02, 2015 - 03:45 PM.


#585 Trav1s ONLINE  

Trav1s

    Got points?

  • Senior Member
  • Member No: 5472
  • 2,603 Thanks
  • 3,750 posts
  • Location: Cedar Rapids, IA

Posted July 10, 2015 - 06:19 PM

A trip to AutoZoneout confirmed that the battery is good.  I will dig in tomorrow and see what I find.






Top