This is the John Deere 40C crawler that I purchased from a fellow I work with. It has had a lot of use but is still in good shape. When I looked at it initially it had been sitting for about three years and the battery was dead. It has a 6 volt electrical system, with a positive ground (instead of the more typical negative ground.) The engine is a vertical twin cylinder unit with that famous "Poppin' Johnny" sound because one cylinder fires at 180deg and the other at 540 deg, leaving a large gap between power strokes.

This particular crawler has serial number 71079 which makes it a 1955 model.

If you have any John Deere specific crawler photo's or information you'd like to see posted, email me and I'll post it in the "Reader Submitted" area below.

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3/16/2002: Daytime shot, my first look at the crawler Daytime shot, first look at the crawler 4/5/2002: Working on getting the crawler back in running shape Here's the engine shortly after the first start up. The smoke has cleared up quite a bit
A rear 3/4 shot after I backed the crawler back into the shed Close up shot of the engine just purring away 6 volt battery. The tray it sits on flips up so that the clutch pedal can work (took me a bit to figure out that's why the clutch wouldn't work) I'm about ready to pull the spark plugs to check them. I've grounded the coil so I can crank the engine and make sure everything spins correctly before starting her up
I'm getting ready to remove the spark plugs to check on them, and add some oil to lubricate the cylinders for the initial fire up Some part of the hydraulic system leaks internally, so I had to chain up the blade or it would drop down in about 5 seconds Another photo with the blade chained up Yet another side shot, that cylinder will have to be rebuilt
4/6/2002 Having a look at the crawler outside Another shot of the 40C Putting the hood back on (the engine is off) My wife, Erika, behind the controls
Another shot of Erika trying the crawler on for size Dropping the blade to work on the engine A look at the valve train. Yuck!
Loaded on the truck, ready to go home Working on the driveway Working on the driveway Working on the driveway
Tearing out some dead hedge Tearing out some dead hedge




After running the crawler around moving grain drills and such, I parked it. Just before heading home, I fired up the crawler again to put it in the shed and noticed that it had an intermittant knocking sound. I shut 'er down and when I restarted the knock didn't go away this time. Shucks.

What an ordeal. I figured that the crank/connecting rods were toast. To check them I had to drop the full length skid plate. That took me about four hours. Sheesh. After dropping the oilpan, the bottom end looked fine, other than a lot of sludge in the oil pan. I pulled the cylinder head off and found the problem. There was a small piece of metal lodged in the top of the rear piston. It didn't appear to cause any damage other than a small dent in the piston so the engine should be fine.

These four photo's show the damage, and the head finally being reinstalled on the block.



Here is a John Deere Killefer, model 8ML-05, scraper that my friend used with the 40C I bought. It has hydraulic raise/lower and the wheels lock in the lowered position for towing between jobs.


(4/5/2002) After replacing the battery, shooting a little oil into the cylinders, and cleaning out the glass fuel bowl and carb, the tractor fired up after about 5 seconds of cranking. Man...the "PB Blaster" oil I used smoked like you wouldn't believe. After about 30 seconds I was starting to think something was wrong but the smoke finally cleared up.

One little detail that really had me stumped was where in the world is the clutch! Some crawlers use a clutch lever, which was absent on this rig. There are two foot pedals, and I figured both were turning brakes. Well...it turns out that the left pedal is the main clutch (just like in a car) and because the battery tray was flipped down, it was blocking the pedal. Talk about feeling stupid! Anyway, after I figured that out I backed her out of the barn and took it for a spin around the gravel lot outside the barn. I'm so anxious to move some dirt with the blade.

Things I need to-do/find-out at this point:

Locate pictures or drawings of what the John Deere 76 blade is supposed to look like from the factory. The JD76 blade on this particular crawler has been modified. One of the support tubes for the grill guard has been replaced with a length of strap iron.

Locate a battery cover/tool box cover.

Figure out what's wrong with the hydraulic system. After the blade is raised all the way up and the control released, the blade drop to the ground on it's own in about 7 seconds. I raised the blade up and used chains to support it, otherwise I have to constantly lift the blade when I'm running the crawler around.

**(4/6/2002) Just got an email from a fellow saying that there is a "float" screw on the valve assembly, and that if the screw is completely out or partially unscrewed, it puts the hydraulic system in a float mode which is why the blade drops down on it's own. Hopefully checking the screw will fix the problem

**Someone also told me that the John Deere 76 blade was origionally installed on the JD 1010 crawler, which is why it's been modified to fit this 40C

**(4/9/2002) Had a look at the "float" screw inside of the valve. It had some burrs on the seat area that I cleaned up on a lathe with a fine file and reinstalled it. The blade stayed up better, but it still drops.

**(5/11/2002) The engine suddenly picked up a nasty sounding knock.

**5/17/2002 Started tearing into the engine to locate the knocking sound. Thought it was the bottom end, connecting rods or somesuch, but turned out to be a small piece of metal sucked into the engine. Caused slight damage to the piston but wasn't anything serious. Taking the skid plate off to inspect the bottom end though was a full day's work. What a hassle.

**(10/14/2002) Finally got motivated to put the tractor back together. The head is now bolted on and torqued, along with the rocker arm shaft. Still missing the intake/exhaust manifold gasket, water manifold gaskets (2), and a carb gasket.

**(10/19/2002) Picked up the missing gaskets from the local John Deere dealer and went about finishing up the engine reassembly. I've discovered what has to be the slickest way to clean gasket surfaces. 3M Roloc disks. I bought an
Ingersoll-Rand IR317 "High speed sander" and an adapter kit that lets it accept the Roloc disks. It strips rust, paint, gasket material, just about everything right off the gasket surface and leaves a nice clean, slightly roughened surface. Saves a tremendous amount of time wiring brushing by hand. I still use a gasket scraper to get off the big chunks but then the Roloc's take over.

After cleaning the valve cover, valve cover mating surface on the head, the exhaust manifold and head, and carb, the rest of the parts went right together. Dumped one gallon of new anti-freeze into the radiator and topped off with water. Probably should have used 1 1/2 gallon instead for cold weather.

The engine cranked for about five seconds until it started and blew black smoke. The fuel in the carb was probably stale, having sat in there since last summer. After that, it cleared up and ran great. I hadn't replaced the oil pan gasket, thinking I could get by. That was a mistake. It leaked like a sieve. I'll have to replace it next weekend. Even with the leak, it ran great and I took it for a quick spin in the driveway, and moved the Killefer scraper from it's spot in the grass.

**(10/26/2002) I emptied the oil out of the oil pan and it was quite dirty. Probably just from cleaning all the gunk out of the engine, but I'll keep an eye on it. Washed off the oil pan good in the solvent tank and cleaned it's gasket surface and the bottom of the block with the IR sander and Roloc's. Bolted her back together and filled with oil. Started her up and she ran great, not a single leak. It looks like the water manifold on the head weeps just a hair, but that went away when the engine got up to operating temperature. I retorqued the water manifold bolts just to be sure.

Tom drug out his steam cleaner and I used it to clean the crawler. Most of the dirt ended up on me!

Next project is to modify the skid plate so it is easier to reinstall, and to finish putting the guards and hood back on.

**(11/2/2002) Finished putting the crawler back together today. Put the hood back on, installed the grill guard supports, front skid plate, and the blade. Oh boy was the blade a pain. The two arms that go back to the frame pivots are supported by an X made out of steel. When I straightened the bends out of them, it moved the ends of the support arms about 1/2" apart so that it wouldn't slide into the pivots. About two hours later, after banging/bending and retrying, the blade was in. I moved some gravel around with the crawler and it runs good. Can't wait to get it home so I can work on it more without having to drive to it.

**(6/15/2003) Tom had a farm auction and sold off all of his equipment but the crawler. Unfortunately the box scraper sold for more than I was willing to pay. We worked a deal out on the crawler so I can still buy that, outside of the auction.

**(8/14/2003) Finally picked up the crawler and packed it home. Picture of the haul is at the top of this page. Worked on the driveway and tore out some dead headge. What a great little tractor!


Reader submitted crawlers:
Anthony Kaluzny's 1953 John Deere 40C
Gene's John Deere 40C


Technical information about John Deere 40C crawlers:
(Information gleaned from John Deere service manuals)

Serial numbers:
Serial number: Year of manufacturer:
60001 ~ 63357 1953
63358 ~ 66893 1954
66894 ~ 71689 1955
Total units: ~ 11,688


General Specifications:
Horspower Drawbar Belt
22.4 24.9
Engine displacement: 100.5cu/in, twin cylinder 4.00" X 4.00"
Engine rated speed: 1850rpm
Tracks: 12" standard Optional:
10", 14", or 12" snow
Track length: 102 inches
Undercarriage width: 67 inches
Weight (base tractor): 4,000lbs
Weight with blade: 6,000lbs
Transmission: Gear: Speed @ 1850RPM:
1st .82 mph
2nd 2.21mph
3rd 2.95mph
4th 5.31mph
Reverse 1.64mph

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