Yesterday's Tractor Co. Parts for Farm Tractors - Compare our Prices!
Click Here or call 800-853-2651 
   Allis Chalmers Case Farmall IH Ford 9N,2N,8N Ford
   Ferguson John Deere Massey Ferguson Minn. Moline Oliver
 FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   Traditional YT Forum ViewClassic View   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

4020 24 volt system dash lights


 
Post new topic    
View previous topic :: View next topic  
Author Message
8850dave
Regular


Joined: 25 Mar 2005
Posts: 267


Report to Moderator

PostPosted: Wed Jan 02, 2013 4:34 am    Post subject: 4020 24 volt system dash lights Reply to specific post Reply with quote

I bought 4020 last summer and have installed new wiring harness, but now oil and generator lites will not light unless I use test light inside power side and test lite is grounded and then the lights come on. Any ideas?
 
Back to top
View user's profile
John T
Tractor Guru


Joined: 14 Dec 1998
Posts: 14037


Report to Moderator

PostPosted: Wed Jan 02, 2013 4:37 am    Post subject: Re: 4020 24 volt system dash lights Reply to specific post Reply with quote

You may want to insure theres a small jumper wire (and if fuzed its good) from the mid tie point of the two batteries to frame ground. Thats where they join in series in the middle NOT either of the two outermost + or - that go to the starter.

John T
 
Back to top
View user's profile
8850dave
Regular


Joined: 25 Mar 2005
Posts: 267


Report to Moderator

PostPosted: Wed Jan 02, 2013 4:51 am    Post subject: Re: 4020 24 volt system dash lights Reply to specific post Reply with quote

I have new cables and did put slow blow fuse assembly on the lh rear post.
 
Back to top
View user's profile
Cliff Nelson
Long Time User


Joined: 26 Mar 2009
Posts: 813


Report to Moderator

PostPosted: Wed Jan 02, 2013 5:57 am    Post subject: Re: 4020 24 volt system dash lights Reply to specific post Reply with quote

It's your 24 volt system messing with you. lol. Seriously, it sounds like some wires may be switched. If you are testing the "power" side and getting the lights to work you have power to the sensor side. A good wiring diagram and understanding of the 24 volt system will help. Check with a volt meter to see if you have +12 or -12 volt in the right place. Also check for voltage at the oil pressure sensor. Probably a simple fix but difficult to find. Good luck.
 
Back to top
View user's profile
tim s
Tractor Guru


Joined: 01 Nov 2008
Posts: 7368
Location: Somerset Ohio

Report to Moderator

PostPosted: Wed Jan 02, 2013 6:40 am    Post subject: Re: 4020 24 volt system dash lights Reply to specific post Reply with quote

You will need to change the wiring a bit,,getting 12 volt to the one side of the indicator light and letting the wire coming up from the oil sender be the ground, the way your hooked up now you have 2 grounds going on,, Like Clif said the 24 volt stuff is still messing with you, they are a strange and unfriendly system....I do away with all of them I can....
 
Back to top
View user's profile
JD Seller
Tractor Guru


Joined: 11 Mar 2009
Posts: 8355


Report to Moderator

PostPosted: Wed Jan 02, 2013 7:12 am    Post subject: Re: 4020 24 volt system dash lights Reply to specific post Reply with quote

I would bet that you have the wrong dash harness. They where 6 or 7 different ones used originally. I think JD has substituted them down to three. So you will need to get a good wiring diagram and make yours correct.

I would bet that Tim is correct in that you have two grounds going to the dash lights.

Also make sure you have the correct ground/positive at the breakers on the back of the dash door. If you have them hooked up wrong they willmake the dash and lights not work correctly.

It makes it easier If you think of the system as being two separate 12 volt systems. One being negative ground and the other positive ground. Nothing on the whole setup sees 24 volt other than the starter and generator.
 
Back to top
View user's profile
tim s
Tractor Guru


Joined: 01 Nov 2008
Posts: 7368
Location: Somerset Ohio

Report to Moderator

PostPosted: Wed Jan 02, 2013 7:30 am    Post subject: Re: 4020 24 volt system dash lights Reply to specific post Reply with quote

Yes jdseller that is a good way of saying it, and I"ll add that the system will need to continue seeing 2 12 volt feeds only now they will both be neg ground, so battery A&B switch post will both be positive when tested . this is the same on the new Gen switches too, they have 2 12 volt feeds to spread the power load, if only 1 has power only about half the stuff will work... If you tie the Blue and Brown wires together down at the starter to the 12 volt terminal it will take the feeds to Battery A&B at the switch, and this would be a good place for a circuit breaker if you don"t already have 2 from the old 24 volt system, those are good and also pricy, so save them...
 
Back to top
View user's profile
Tom 43
Long Time User


Joined: 20 Feb 2008
Posts: 1348


Report to Moderator

PostPosted: Wed Jan 02, 2013 11:10 am    Post subject: Re: 4020 24 volt system dash lights Reply to specific post Reply with quote

The generator light is fed from the negative terminal of the battery, then to the switch which contains a resistor, then to the GEN light, and then to the GEN terminal of the voltage regulator which in turn goes to the output terminal of the generator. When the switch is turned on, current flows as described above to the generator output terminal and through brushes, through the armature and then finds ground back at the positive terminal of the second battery. The purpose of the resistor is to enable the use of a 12 volt bulb for the GEN light instead of a special 24 volt bulb.

To trouble shoot the generator light circuit, 1) Unhook the wire at the GEN terminal of the regulator that goes to the GEN light. Place the positive lead of a voltmeter on the positive terminal of the second or ground battery. 2) Connect the negative lead of the voltmeter to the unhooked wre going to the GEN light 3) Turn the switch on and you should read 24 Volts. 4) If you don't, keep reading backwards through the circuit with the negative lead of the voltmeter until you do.

To check the oil light, check the integrity and continuity of the small wire that goes from the tractor frame to the center of the two batteries. 2) If the wire has continuity, unhook the oil light wire at the oil pressure sending unit. Place the positive lead of the voltmeter between the batteries and the negative lead on the unhooked wire from the OIL light. Turn the switch on and you should read 12 VOLTS. 3) If you do read 12 replace the sending unit. 4) If you don't back track the oil light circuit with the negative lead of the voltmeter until you do and fix the problem.
 
Back to top
View user's profile
Display posts from previous:   
Post new topic    Yesterday's Tractors Forum Index -> John Deere All times are GMT - 8 Hours
Page 1 of 1

 
Jump to:  
TRACTOR   PARTS TRACTOR   MANUALS
Same-Day Shipping! Most of our stocked parts ship the same day you order (M-F).  Expedited shipping available, just call!  Most prices for parts and manuals are below our competitors.  Compare our super low shipping rates!  We have the parts you need to repair your tractor.  We are a Company you can trust and have generous return policies!   Shop Online Today or call our friendly sales staff toll free (800) 853-2651.

YT Home  |  Forums Home

Copyright © 1997-2014 Yesterday's Tractor Co.

Powered by phpBB © 2001, 2005 phpBB Group

All Rights Reserved. Reproduction of any part of this website, including design and content, without written permission is strictly prohibited. Trade Marks and Trade Names contained and used in this Website are those of others, and are used in this Website in a descriptive sense to refer to the products of others. Use of this Web site constitutes acceptance of our User Agreement and Privacy Policy

TRADEMARK DISCLAIMER: Tradenames and Trademarks referred to within Yesterday's Tractor Co. products and within the Yesterday's Tractor Co. websites are the property of their respective trademark holders. None of these trademark holders are affiliated with Yesterday's Tractor Co., our products, or our website nor are we sponsored by them. John Deere and its logos are the registered trademarks of the John Deere Corporation. Agco, Agco Allis, White, Massey Ferguson and their logos are the registered trademarks of AGCO Corporation. Case, Case-IH, Farmall, International Harvester, New Holland and their logos are registered trademarks of CNH Global N.V.

Yesterday's Tractors - Antique Tractor Headquarters