Jump to content
ScottyBones

My tractor melted

Recommended Posts

On September 17th 2017 at aproxamitly 6:37pm a catastrophic anomaly occurred while trying to start my 69 C-121 Auto after a long day of use. There was alot of smoke and alot of fire. Upon investigation I came to the conclusion that the lens on the ampmeter wich holds it in place broke causing a chain reaction of unfortunate events. The meter fell behind the dash grounding itself to the chassis. At this point the entire ampmeter circuit became glowing red. Moments later the Smokey wires burned through my fuel line causing a fire to erupt from under the dash. Luckily the fire soon outed itself but it wasn't over yet. By the time I ran to the garage for a pair of clippers to cut the battery cable a hot wire melted through the choke cable. The choke cable was grounded to the engine and all 2 feet of it melted the outer plastic coating and was glowing. At 6:57pm the 121 was pushed into the garage for emergency surgery. 

 

So now I need to rewire the entire tractor. My only concern is the voltage regulator. The connector on it is melted pretty bad. I can fix the connector but im worried that the regulator is damaged. Is there any way I can check it before I rewire it all? I really don't want this to happen again especially after a full rewire. 

20170918_191343.jpg

20170918_191410.jpg

20170918_191418.jpg

  • Sad 6

Share this post


Link to post
Share on other sites

Sorry to hear of your misfortune, at least the fire didn't get out of control.

This thread on diodes may be helpful, unfortunately the photos were lost to photo-bucket.

 

Share this post


Link to post
Share on other sites

After a fire, if a part is questionable, replace it. Like you said, you don't want it to happen again.

  • Like 1

Share this post


Link to post
Share on other sites

I don't know why there wasn't  more fuse's on these tractors.  My c160 had 1 fuse for the lights only. After I rewired it I have 2 fuse's .

1 for lights and voltage meter  and 1 for tach. I replaced the AMP gage with a volt meter. I probably should have added a 30 amp fuse for the battery to starter solinoid.

The later models have a lot of fuse's. 

I would rewire it all if it were me because it could have  melted  the wire insulation on all wires.

Edited by BOB ELLISON
  • Excellent 2

Share this post


Link to post
Share on other sites

Thanks for everyone's help. I was planning on switching to a volt meter as Well. The schematic I'm looking at shows 1 side of the amp meter going to the positive on the battery and the other side going to the solenoid. Should I wire a voltage gauge the same way?

Share this post


Link to post
Share on other sites

All operating voltage normally passes through the ammeter, so if you are removing it, just connect both of those wires (the one from the solenoid/battery and the one from the ignition switch) together. They should be red and light green. Then, if it was mine, I'd take a wire from the accessory terminal on the ignition switch (the same one the lights are connected to) and connect it to the plus side of the volt meter, and connect the negative side to ground. That way, the volt meter will only be drawing voltage when the key is on, keeping the battery from draining when the tractor is off.

Also, a good rule of thumb for the models like yours with a cradle-mounted engine is to check the ground wire that connects the cradle to the frame.

  • Like 4

Share this post


Link to post
Share on other sites

This diagram is for my c160 after I rewired it. The green wire is where the amp gage was. And the volt gage is tied into the light circuit just as rmaynard said.

volt meter22.jpg

  • Like 3
  • Excellent 1

Share this post


Link to post
Share on other sites
8 hours ago, rmaynard said:

All operating voltage normally passes through the ammeter, so if you are removing it, just connect both of those wires (the one from the solenoid/battery and the one from the ignition switch) together. They should be red and light green. Then, if it was mine, I'd take a wire from the accessory terminal on the ignition switch (the same one the lights are connected to) and connect it to the plus side of the volt meter, and connect the negative side to ground. That way, the volt meter will only be drawing voltage when the key is on, keeping the battery from draining when the tractor is off.

Also, a good rule of thumb for the models like yours with a cradle-mounted engine is to check the ground wire that connects the cradle to the frame.

Actually current runs thru the ammeter not voltage.

Share this post


Link to post
Share on other sites
11 hours ago, ScottyBones said:

On September 17th 2017 at aproxamitly 6:37pm a catastrophic anomaly occurred while trying to start my 69 C-121 Auto after a long day of use. There was alot of smoke and alot of fire. Upon investigation I came to the conclusion that the lens on the ampmeter wich holds it in place broke causing a chain reaction of unfortunate events. The meter fell behind the dash grounding itself to the chassis. At this point the entire ampmeter circuit became glowing red. Moments later the Smokey wires burned through my fuel line causing a fire to erupt from under the dash. Luckily the fire soon outed itself but it wasn't over yet. By the time I ran to the garage for a pair of clippers to cut the battery cable a hot wire melted through the choke cable. The choke cable was grounded to the engine and all 2 feet of it melted the outer plastic coating and was glowing. At 6:57pm the 121 was pushed into the garage for emergency surgery. 

 

So now I need to rewire the entire tractor. My only concern is the voltage regulator. The connector on it is melted pretty bad. I can fix the connector but im worried that the regulator is damaged. Is there any way I can check it before I rewire it all? I really don't want this to happen again especially after a full rewire. 

20170918_191343.jpg

20170918_191410.jpg

20170918_191418.jpg

 

The voltage regulator is more than several diodes and since you cannot take it apart you cannot check it. It contains a few diodes and also regulation that limits the output voltage.  My suggestion would be to put it on the bench and feed it AC on the AC terminals, a ground via the case probably, and a battery just like you would have on your tractor. If you happen to have a variac you can easily dial up the AC voltage feeding it and also measure the DC voltage from it as its connected to the battery. If you don't have a variac and happen to have a transformer that is close to the AC that would be supplied from your stator then connect the transformer to the regulators AC input and check the output. 

 

Also one might want to make up a cord that has a light bulb in series with the hot leg. Plug the transformer into this cord/receptacle.

 

This will protect the transformer and will light brightly if the regulator is shorted thus saving the transformer you using for test purposes.

  • Like 1

Share this post


Link to post
Share on other sites

You can get aftermarket regulators on ebay for under $30.  Three terminal connector bodies do not seem to be available anymore.  I just bought 4 terminal bodies

  • Like 1

Share this post


Link to post
Share on other sites

I'm with @doc724 replace the regulator. Unless you can test it and be sure it will not damage the battery. I would feel safer to buy a aftermarket. 

This post will show you what could happen.

 

 

  • Like 1

Share this post


Link to post
Share on other sites
7 hours ago, 6bg6ga said:

Actually current runs thru the ammeter not voltage.

Technically you are correct, however disconnect one of the wires and you won't have any voltage either. 😀

 

 

  • Like 1
  • Thanks 1

Share this post


Link to post
Share on other sites

I think I'm going to take everyone advice and replace it with an aftermarket. I found a sparkly one on eBay although I couldn't find any connectors. Does anyone have a link?

  • Like 1

Share this post


Link to post
Share on other sites

Just put three new 1/4" insulated female spade connector on the ends of the wires.

spade.jpg.ae2489b73f1d8b9d0e16a5150bfbe125.jpg

 

The white wires go to the terminals marked AC, and the other goes to DC or B+

 

Here is a link to a new regulator on Amazon for $32.70 with free shipping.

https://www.amazon.com/Regulator-Rectifier-Kohler-Engine-Engines/dp/B004QIE2Q0

 

 

 

Edited by rmaynard
  • Like 1

Share this post


Link to post
Share on other sites

There was a site that sold the connector with about a foot of wires coming out of it. It was well made and colored wires but I can't find it now. I saved it on my phone and samsung thought I needed there Internet search engine and deleted all my saved sites. I deleted samsung  search engine. 

  • Sad 1

Share this post


Link to post
Share on other sites
1 hour ago, BOB ELLISON said:

There was a site that sold the connector with about a foot of wires coming out of it. It was well made and colored wires but I can't find it now. I saved it on my phone and samsung thought I needed there Internet search engine and deleted all my saved sites. I deleted samsung  search engine. 

Are you referring to a 3-prong harness, or the one for the ignition switch like the one below?

haeness1.png.927b488ccaeb53c2fa5b8059839829d3.png

  • Like 1

Share this post


Link to post
Share on other sites
3 hours ago, rmaynard said:

Technically you are correct, however disconnect one of the wires and you won't have any voltage either. 😀

 

 

You are correct. All current passes thru the ammeter and thus the positive leg. Disconnect the positive and your dead in the water.

Share this post


Link to post
Share on other sites

@rmaynard yes it looks just like that but it's a 3 post for the regulator/ rectifier .

Looked just like scottybones .

Someone had them for sale and I lost the page.

  • Like 1

Share this post


Link to post
Share on other sites

If there is room in the engine shroud you could use a Onan  http://www.ebay.com/itm/New-Voltage-Regulator-Rectifier-For-John-Deere-Onan-318-420-P-B-Engine-16-20HP-/391723779094?hash=item5b348e8416:g:57wAAOSw4CFYwPZg

 

At a cost of $12.66 in place of the more expensive unit.  Same hookup  (2) AC terminals, one B+(12VDC battery) and the chassis ground to the regulator case.  If no room simply mount a 12 vdc fan to cool the regulator case.

Share this post


Link to post
Share on other sites
On 9/19/2017 at 2:58 PM, ScottyBones said:

I think I'm going to take everyone advice and replace it with an aftermarket. I found a sparkly one on eBay although I couldn't find any connectors. Does anyone have a link?

 

I bought the connectors and terminals on ebay from a company called MJMNational (at least that is how the Paypal showed up on my credit card).  Had to buy some minimal number of connectors and terminals but it way cheaper than getting them from other sources and paying a hefty shipping cost.  If you go the route suggested by Bob Maynard, that is perfectly fine, just make sure you use tin plated connectors.  Unplated brass will become a problem down the road.

  • Like 1

Share this post


Link to post
Share on other sites

Alright so I orderd the one 6bg6ga mentioned. Should be here sometime next week. I grabbed a handful of connectors from work and picked up some wire. I was going to start it this weekend but im not going to have the time. I will post a progress update next week. Thanks again for everyone's help. 

  • Like 1

Share this post


Link to post
Share on other sites

Alright I got everything re wired and tractor runs great. Getting 14 volts at battery post at WOT. I removed the amp gauge. One side of it when to the starter solenoid the othere when to ignition Switch. Basically all I did was shorten the wire and istead of going from the ignition switch to the solenoid I ran from switch directly to the positive battery terminal. Is this ok or does it need to be on the solenoid? Either way it's still 12v all the time. Also I'm going to add a fuse to the same wire. What size should I use? I was thinking 20amp as when the amp gauge was working I never seen it get that high. 

  • Like 1

Share this post


Link to post
Share on other sites
3 hours ago, ScottyBones said:

 ...I ran from switch directly to the positive battery terminal. Is this ok or does it need to be on the solenoid?

Either location is fine. I would use a piece of 14 gauge, stranded wire.

 

  • Like 1

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Recently Browsing   0 members

    No registered users viewing this page.

×