4020 information

amo

Member
What to look for when looking at a 1968 John Deere 4020, any good and bade would be appreciated. Thanks Amol
 
The big thing is transmission operation. If it's a synchro, Does it go into and stay in the selected gear? Does it shift within a range without grinding regardless of rolling or not?

If its a powershift does it shift into all gears including reverses without serious hesitation? Is the transmission able to hold rated pressure at rated engine speed even when warm? Does the powershaft engage when commanded and stop when commanded?

All other things to look at are just like any other piece of equipment. Does it keep good engine oil pressure when warm? Does it smoke, or have blow-by? Is the differential noisy? Do the brakes chatter? Are the hydraulics responsive and quiet?
 
Any chance you can work it before hand ?

Buying from a local you can sort of trust is worth paying extra for !

I still can't believe so many buy sight unseen or at a consignment auction that you have no idea what the history is.
 
I will buy at a sale because it usually $3000 cheaper than at a dealers lot. I can drive most tractors for 5 minutes and tell mostly what they are like. I do my own repair work so if I end up with a problem tractor I fix it. I can rebuild the engine in a 4020 for less than $3000 and then it is new. Any tractor will need fixed if you own it long enough. Dad always said you had two choices parts or payments. There is nothing wrong with buying from a dealer if you have the extra money but as a small farmer we have always bought cheaper tractors and we did sometimes fix them. Tom
 
I should of said buy local as in from an individual not really from a dealer.
Dealers usually get WAY more for their items and many times they get the ones traded in that are not as good of condition. The best ones will usually sell right away before a dealer ever sees them. Or if the dealer does take a good one in on trade it won't be on the lot as it gets sold before the paperwork is done they usually have a list of buyers to contact.
 
I always see how it starts and if it starts without starting fluid. Some of them you have to rock the steering wheel back and forth to crank it which is no big deal. If it's a synchro shift transmission make sure it stays in gear some times if they have some wear you have to feel around for the gear but as long as it stays you are good. If it's a power shift make sure it hits all gears. Make sure the 3 point goes up and down. PTO comes on and off. Just the basic stuff when checking out a tractor.
 
(quoted from post at 21:23:50 01/22/15) What to look for when looking at a 1968 John Deere 4020, any good and bade would be appreciated. Thanks Amol

Look for excessive wear on clutch/brake pedals plus wear on drawbar & 3pt draft link balls.
 
Some really good advice here already. I'll add a couple tips.

Engine:
You want to make sure it can start unassisted. The perfect temp for me to really know how it's gonna start is 35-40. The faster it fires, the better. If the owner/dealer has had it running and warmed up when you get there, best to schedule to look at it some other time because that's the oldest trick in the book. Check the blowby and check the smoke. Lots of white smoke is bad.

Trans:
Check the gearshift to see how much slop it has. With the tractor running, see how it shifts. Does it miss gears? Does it grind? Check out the syncros to see if it will shift forward and back when rolling. Feel the clutch and check how much clutch life is left.

Hydraulics:
Check the steering and check the 3pt lift. The 3pt arm jiggle can indicate a pump needing some attention. Check the hyd oil to see what the level is and the condition of the oil. Hyd oil that is dirty or shows signs of water may indicate neglect of maintenance.

Leaks:
Obvious ones are steering motor and hyd. pump seal, motor or fuel pump, load shaft, pto seal and hyd. outlets. Some of these are more prone to leakage than others. On the older 4020s if the weep holes are leaking or show signs of leaks then you know a rebuild is in the future.

Sheet metal:
The condition of the metal depends on how you intend to use the tractor. The metal may be acceptible as is. If you are looking for one to restore then you want to get the straightest metal you can find. Some dings and dents can be filled easily enough. If the front of the hood is bashed in, that's a tough one. Hoods for the older tractors are easier find though. Check the bottoms of the fenders for rust. Most of the other panels can be replaced easily enough if they are damaged so I don't put too much emphasis on them.

In general you are checking for wear. The hour meters on 40 year old 4020s typically do not work or have been replaced. So you can't strictly go by the meter unless you really trust the person telling you it's the original tach. Just be very skeptical if seems low. For me it's nice to know how many hours the meter shows but I don't base my whole buying decision on the tach alone. A good rule of thumb I use is to always look at how much of the plastic coating is remaining on the gearshift knob. Syncro obviously. That coating seems to stay fully intact to around 6k-7k hours give or take. If someone says their 4020 has 5k hours and that plastic is half gone, then they are full crap. Nowadays I see a lot of pretty slick painted 4020s, but the gearshift has no sign of plastic left--- You know right away that these are terribly high houred tractors without wasting your time to go see them. My philosophy is that you can paint a turd, but it's still a turd. I can't stand some of these spray bomb jobs these places are putting on tractors to get them thru auctions or whatever. Yes that shiny paint brings more money unfortunately, but that doesn't mean it was a good tractor or that any mechanical issues were addressed before it was painted. People are buying those things without seeing them in person or taking a test drive and that's risky. Like previously stated, a 5 minute test drive can tell you a lot. So I am very wary of any tractor with 'fresh paint' unless it has had an actual restoration. Lastly, I look at the seat and floor plate. If the floor plate is deeply pitted, that means the tractor sat out a lot. A seat that is sloppy loose or leans to the left indicates a lot of wear and neglect. A seat that is froze up and won't adjust also typically means it sat out a lot.

Just keep in mind that many times a tractor is for sale because it has problems and needs attention or a bunch of money dumped into it. And remember, owners are always upgrading or downsizing, so take that with a grain of salt.

Having to put some money in an old 4020 is just a reality. But some things are more costly than others. If I find a really nice tractor that just needs tires, I don't mind so much. Tires can be bought, but good honest tractors are hard to find. I'd much rather have a tractor that needs tires and is mechanically good than a tractor that has new tires and new paint but needs an overhaul and trans work. Don't be afraid to put it through it's paces and get it good and hot during your test drive. Don't be afraid to spend a little more for a good one either. Buying the cheapest one is gonna get you in trouble. In other words, go tractor shopping not price shopping.

68 was a good year for 4020s IMO. I have a 68 and I love the way it sits and feels. It fits me far better than any of the side console 4020s. Consoles are nice but it seems like the seat is too high or the steering wheel is too low. Hard to explain but the older ones are more comfortable for me.
 
I agree with everything you said except about the weep holes. The latter tractors do not have them so you have no way of knowing anything. Those holes can seep for thousands of hours use and years. I would much rather see engine oil leaking from one than antifreeze. I have several tractors with plugs in them and we just check the oil because some day the antifreeze may end up there.If the rest of the tractor suits and the price is right I would not worry to much about the weep holes.
 
I was just going by what op said. He said he was looking at a 68. True the newer ones don't have them. It is definitely an area to look at and not ignore. I would not want to buy one with oil or anti-freeze oozing out the weep holes with the expectation that you could go thousands of hours without opening it up. Be my luck it would need a OH as soon as I got it home. A first time buyer should error on the side of caution. If yours is weezing but you're keeping an eye on it, then that's a little different.
 
Many things and an experienced set of eyes helps.I have bought many tractors and one of the first things is check PTO ,blow-by,clutch if syngro,tires[easy],W.F. for repairs ,if it has correct hour meter,air filter,seat suspension.If you are serious a JD inspection for around $200 might save you a lot of problems and $s as if done right they check pressures and find small details as they want to fix it and sell parts.Many sellers will work with you.When I first started selling them I had them all inspected.I have seen them at consignment sale with inspection included.A guy told me at a sale all tractors are not bad but all the bad ones are here.I know of a couple bad deals so best be sure before you drive it off lot.A ride and drive is not too much to ask for.Buying private isnt always the answer.
 
I have high respect for the gentlemen below so follow their comments. I did not see:

Water in Oil?
Oil in anti-freeze?
Make sure you warm it up and operate it over it's full throttle range!
Check radiator. Does it leak? Did it leak? Bought a tractor once, had a bad radiator, come to find out it was run really hot and knocked at high rpm when warmed up. Piston sides were literally burned.
Wiggle fan, is water pump bearing tight or loose?
Are axles straight? Yep bought one with a bent rear axle.
This has been covered but front ends can be money pits in and of themselves.
If you could get engine and transmission oil samples and quickly check them that would be best. But, my experience has been it takes awhile to get results. I bought a nice PS from a dealer once. I could not figure out why he wanted to sell it. A year after I got it I found water in the oil. To this day I wonder if he knew the O-rings were going and caught it in the early stages with an oil test.
Same thing on a Synchr, I bought it from a dealer over the phone. I made a couple mistakes on that one, I got the serial number but he never sent me the first digits. Turns out it started life as a gas and was retrofitted as diesel. The rear end makes noise, the oil test says "STOP" immediately. (But to date I keep using it, my use is low hours.)
The same one with the bent axle knocked like crazy when warmed up and run at high speed. My son took it apart, the crank, etc. were far out of spec. we just put in a REMAN. We believe it was run without oil. Not proud to admit it, but lessons learned.
Paul
 
First thing I do is ask that the seller not start it for at least 24 hrs before I look at it. Bring your 1 1/4 wrench along and loosen the engine oil drain plug till fluid starts to seep and look for water or antifreeze. It still be at the bottom of the oil pan if present in the crankcase
 

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