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Toro Wheel horse 520-H engine will not start (electrical issues)

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Well I finally paid attention and gave more then a glance and a tug, to connector 29.   It is falling apart and I probably banged it when changing the oil filter when servicing which was the beginning of this problem.  It actually  "fell apart in my hand" when I pulled to separate the connection. 

 

It seems however it, that the connector cap (NN10281) has been discontinued by Toro with no replacement.  The contact socket (NN10279) is still available.  I presume that any similar matching male-female connector that would accommodate the correct number of wires to mate them would work fine.  Any suggestions where I might get them?

 

I suspect that new connector and socket will fix the starting problem and will post either way.

 

Thank you Geno and Km3h for being generous with your time and knowledge, and patience with me as I stumbled around seeking a solution.

 

Stephen

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The connector is for ease of removing the engine. The connector and pins are available in lots of places, just do a search for "9 pin molex".  Radio Shack has a lot of connectors also.  There are 8 wire positions in there if I remember correctly.  If you aren't worried about putting it back factory you can always eliminate the connector, not something I do but I have seen it done plenty.  You can also split it into 2 separate 4 wire plugs if you have less trouble with finding them. 

 

To get it going temporarily if you need to use it take the broken ones only, cut the wire on the other side close to the connector and wire nut and tape them together until you get what parts you need.   :)

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Check this thread. Martin is a genius at this stuff. If you go through this thread, you will find the answers to where you can get the necessary parts to fix that connector. The first link will show you what you need to do. The second link is to the entire thread. Somewhere in there is a description of exactly what he used, the part numbers and where he bought them.

 

 

   http://www.wheelhorseforum.com/index.php?app=core&module=search&do=search&fromMainBar=1  

 

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Please, if you start cutting wires, at least take photos so you can see how to put them back together.

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A search engine should be every ones best friend.  Here's a hundred links to the connector you need. They are used everywhere.  I think the first ones I replaced were in pinball machines in the 70's, you have the same one on your tractor.     https://search.yahoo.com/search;_ylt=AvmmxioA.ocd2t.9xtCX5PKbvZx4?p=9+pin+molex+connector&toggle=1&cop=mss&ei=UTF-8&fr=yfp-t-250&fp=1

Edited by Geno
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 I got the molex connector at radio shack this after noon and spent time to diagram the wiring as it exists at that connection, as not every wire is a color match.  Then I checked it and found that my 21 year old dirty wiring can easily be misidentified and corrected my errors, then checked it again just to be sure.  So I have a diagram of the plug and socket wiring.

 

After messing with the male end of the molex connector to strip and make up the leads for the discovered that the other end that I was connecting to was very short, and it would be a near impossible job to get the tools into the tight space.  A simpler solution will be to make male & female connection for each of the 9 wires, then encase them in a cut off piece bicycle tire tube with a few cable ties.  This should protect the wiring from the weather, and I will add to my owners manual the color to color connection if I ever need to work on it in the future.  This will allow the wiring to be disconnected if necessary and provide a much easier fix the the molex connector.

 

Geno and Nick I can't thank each of you enough.  The support and ideas when I was stuck in the dark provided a ray of light that I so appreciate, and  I did learn a lot about wiring on the 520-H in this process, even in my struggle.  Thank you both for your generosity and  sharing your wisdom.

 

Stephen

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Whenever you run into non color matches or anything at all it's always best to do 1 at a time.  Makes life easier.  :)

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I can't speak for Gino, but I for one am glad that we were able to help. I know that from time to time I run into problems I don't understand or can't find a solution for. That's when I come here or if it is related to another product I find the right forum and seek answers. When it comes to Wheel Horse, this forum has never let me down.

 

If you haven't already done so, I strongly advise taking photos of that connector before you dismantle it. A photo is worth a thousand words, especially since it will enable you to see the different colors of the wires and their placement in that connector. It is very easy to become confused when working from a had drawn sketch when wiring.  

 

Good luck and be sure to get back here and let us know how everything turned out.

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I cut the wires off both sides of the molex connector leaving enough sticking out to identify the wire color going into the molex and coming out the other side.  I had made a diagram but once the connector was out it provided a physical wire-to-wire match.  

 

I replace the molex connector with 9  individual  Male or Female connectors, then plugged them together according to the wire to wire connection on the cut out molex.

 

I now have dash lights and headlights when I turn the switch and a click, but it still no start. (so there i power at the switch)

There is constant power at the 30 and 25 Amp fuses, and switched power from the key on the 15 Amp lighting circuit.

The starter engages when I connect a jumper from the battery to the solenoid.

Both the seat and PTO switches seem to be ok.

 

I am surprised how calm I feel today, and I am very thankful that the faulty molex connector quit now, and not in the middle of winter with 18" of snow out of my 600 foot driveway.

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If you have a click at the relay then everything is good to there.  You can check the connections at the starter and starter post on the relay next.  Also make sure the battery isn't low and has good hot and ground connections.   :)

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The Solution is discovered:

-----------------------------

previously on Sept 22 I posted:

"A new question:

There is a connector that was loose behind the battery with blue, brown, purple wires which would seem to be part of the seat safety switch, the leads are only about 4 inches long with nothing in sight within reach to plug it into.  Perhaps this wiring harness could be used for another setup?"

----------------------------

I kept coming back the this floppy switch hanging with no place to plug in, I know it was the missing link but could find no place to plug it in.  Quite by accident I viewed some pin connectors from just the right angle and saw them slightly protruding from the back side of the center brace in the in the battery compartment.  I did not remember that it came loose when I was replacing the the throttle cable.  I really feed dumb for not finding this before, or remembering it came off when I was removing the old throttle cable.  Once plug in It started.

 

Again thanks for all the moral support that kept me going until I could get my head clear and see the obvious.  And the exercise has provided a much better understanding of the electrical system of my 520-H.  And in the process I discovered the corrupted connector 29 that was failing, but probable would have not died completely until the first heavy snow.

 

Best regards, Stephen 

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That's terrific. Learning by experience is the best teacher. Hope you get many more years of work and pleasure out of that 520.

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Funny thing is, you learned on the worst  :wh:  I've encountered.  Once into the 400, 300 or older series you look under the hood and there's very few wires.  You've been properly broken in.    :laughing-rolling: 

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Where is the multi pin 9 pin connector located on a 520H?

 

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Right in back of the motor, can't miss it. White plastic block with a boatload of wires going in and out of it. If you have a bad one there is a guy here @rmaynard that has them.

 

BTW :WRS:

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