Wiring diagrams, 1972 4020

Does anybody have a wiring diagram(s) for a late model, 1972 4020. It has the 2 6 volt batteries in series, no cab, one fender light on each side. Serial #265510

I went to my local JD place today, and the man there was nice enough to run me off a couple pages. They are:

[i:e0d29270e1]SM-2035* (May-66) Fig 190-40-7 Engine and Instrument Harness Wiring for 4020 Tractors 91000 and After with Diesel Engine[/i:e0d29270e1] -This looks like its for a tractor with two 12 volts in parallel.

[i:e0d29270e1]SM-2039 (May-66) Fig 190-40-16 Lamp Harness Wiring for 4020 Row-Crop Tractors 119000 and after[/i:e0d29270e1] - This one may be correct, but it definitely shows 2 lights on each fender, and I only have one.

(The 1st one says SM-2035 but I'm pretty sure it was in the same book (cd) as the second page)

Can anybody verify if these are correct or not, and it would be awesome if somebody had the correct ones. I can post images of these if you want, but I am pretty sure these are from the wrong service manual. I don't really want to go back and pester him again unless I have to, it seemed he wasn't having a good time with the book-on-cd as it was. It would be nice if JD would put this stuff online.

As always, thanks for any help you may have. I wouldn't even bother to own tractors if it wasn't for this board!

Those diagrams will not be correct. You need the diagrams for serial number 250,001 and up. The diagrams you have will be totally different. Mike

Only one light in each fender ? Maybe it is a 4000 ???
Don't know if it matters between it and a 4020 for wireing harness but they only had 1 light each side when new.

JDparts shows 4020's > SN 250,000 have 2 headlights on each side.

I can't really argue with Tx Jim, because you obviously know your stuff. But I think I've read on here before that the very last 4020's had a single light on each side. Maybe a part diagram of the piece that holds the lights under the fender would show something different?

This thread shows one restored that has a single light setup http://search.yesterdaystractors.com/cgi-bin/viewit.cgi?bd=jd&th=485138. I have seen the single light mentioned in some other threads.

Pretty sure its not a 4000. For one, I think those have the open battery tray (mine has full boxes), and the 4000's don't have the sheetmetal around the rockshaft.

Jim, the second headlight on a 4020 above serial number 250,001 and up was optional. They only had one standard. Mike

I have 4020 #254532 with one light in each fender. Plate in fender that lights mount to has "dimple" for 2nd light, but no hole for 2nd mounting bolt.

69 year had 2 headlights in ea fender. One light with foot operated dimmer switch came along in 70 or 71.

Jim

(quoted from post at 16:58:49 10/11/13) Jim, the second headlight on a 4020 above serial number 250,001 and up was optional. They only had one standard. Mike

Click to expand...

Thanks for the correction. I couldn't remember the number of headlights(Old Timers or Some timers) even though I sold new 4020's. I was just posting parts information but it's odd parts descriptions & footnotes doesn't mention single/dual headlamp option
LAMP WIRING
(TRACTOR SERIAL NO. 250001- )(ROW CROP)

I feel better knowing its the correct model now. Does anybody happen to have the correct wiring diagrams for this particular 4020?

Thanks for all the info so far.

Not sure what the serial number break was, but the
earlier headlights used 2 on each fender with one
being a "low" powered flood light and the other
being a "high" powered spot light. When the light
switch was in the field position, both would be
lit as well as the work light off the back of the
tractor. When the switch was in the 1st of the
two "road" positions, both beams would be on with
only the red light off the back of the tractor.
To switch between the "high" and "low" beams while
on the road, you had to reach down and turn the
light switch to the last position which turned of
the spot light "high" beams.

This was replaced with a single headlight that had
dual beams and a dimmer switch that was a push
button operated by your foot.

Just to follow up on this, I finally found the correct diagram by ordering the JD shop manual. On CD-Rom, JD sells it for about $40.