1937 3 HP John Deere EP

Green and clean

john deere 1

This view of Richard Dechant’s 1937 3 HP John Deere Type EP engine shows the enclosed cylinder head, air cleaner and enclosed pushrod. The assembled pushrod is attached to the crankcase with the packing gland nut.

Photo by Richard Dechant

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1937 John Deere Type EP
Manufacturer: John Deere, Waterloo, Iowa
Year: 1937
Type: EP
Horsepower: 3
Bore: 4-1/2-inch
Stroke: 5-1/2-inch
Flywheel diameter: 20-3/4 inches
Flywheel width: 2 inches
Governor: Hit-and-miss
Ignition: Sparkplug with WICO impulse magneto

John Deere introduced the EP stationary engine in 1937, starting with serial number 343975. The EP engine was designed primarily to power John Deere implements and as an all-purpose engine for the dusty conditions of Southern potato and peanut fields. The “E” stands for “environment” while the “P” stands for “protected.” The EP engine is also called the Southern E and the peanut engine.

Some of the EP engines were shipped from the factory to Deere & Webber Co. in Minneapolis, Minn. There, the oil bath air cleaner and the large muffler were removed and replaced with the regular 3 HP Type E mixer body (part number E 89 RT) and muffler (part number AE 70 RT). The Deere & Webber branch house sold these engines on the Dain No. 14 hay press. (Our generation would know the hay press as a hand-feed and hand wire-tied hay bailer.) This engine became know as the Northern EP.

The EP engine was only made in the 3 HP size, with an enclosed head and pushrod to protect the valves and exhaust lever from dust. The EP engine also has an oil bath air cleaner, main bearing dust shields and a cover for the water hopper. The crankcase is vented. The muffler used on the EP is similar to the muffler used on the John Deere BR tractor. The hit-and-miss governor controls the RPM of the engine by eliminating the power stroke (the pushrod holds the exhaust valve open until the engine RPM decreases). The WICO impulse magneto will fire the spark plug on every fourth piston stroke, even though the exhaust valve is being held open by the hit-and-miss governor.

The search begins
Before buying my 1937 John Deere EP engine, I made a list of the casting/part numbers along with pictures of the individual parts that make up an EP engine. (The casting/part numbers and pictures were copied from the January 15, 1945, Repair Catalog No. 4 – T for John Deere models “E”, “EK”, and “EP” Engines.) With my list in hand, I set out to find a John Deere Type EP engine. The following is the result of my research.

The enclosed cylinder head
The front of the cylinder head is completely enclosed to protect the intake and exhaust valves, the exhaust lever pivot-bearing surface and the pushrod pivot-bearing surface from dusty environments. The exhaust lever is lubricated with an oiler cup on the end of the exhaust lever cap screw that extends to the top of the enclosed cylinder head.

The valve release plunger is used to hold the intake valve open in order to crank the engine without compression and for stopping the engine.

I made my own valve housing cover gasket by using the valve housing cover as a pattern and tracing the outline onto 1/16-inch-thick oil resistant cork gasket material. The gasket can be cut using a pair of scissors. The five screw holes can be cut with a paper punch. I used 3/16-inch-thick F5 felt from McMaster-Carr (catalog number 8341K36) to make the felt washer and a 7/8-inch outside diameter fender washer for the end of the valve release plunger. To replace the valve release plunger spring, I used a 7/16-by-0.032-by-2-1/8-inch compression spring.

The pushrod assembly
The pushrod is enclosed in a 3/4-inch outside diameter thin-wall steel tube. Both ends of the tube are sealed using fiber packing. The crankcase for the EP engine has a large metal surface cast around the pushrod hole. This allows for the 1-inch by 12- National Fine threads packing gland to screw into the crankcase.

For the pushrod tube packing, I used one 3/4-inch inside diameter by 1-inch outside diameter rubber O-ring and three 3/4-inch inside diameter by 1-inch outside diameter copper crush port gaskets (Restoration Supply Company catalog number GAS040) on both ends of the pushrod tube. The rubber O-ring will mate with the concave surface at the bottom of the pushrod hole.

The oil bath cleaner
The EP engine has an oil bath air cleaner to remove dust from the air before entering into the combustion cylinder.

The air cleaner (part number AE 369 RT) has a brass tag at the bottom front with the following information: “Service air cleaner daily; remove oil cup; empty oil cup; scrape out dirt; refill to oil-level bead with engine oil; replace oil cup securely.”

Making new gaskets
As with the valve housing cover gasket, I made my own air cleaner gasket by drawing the outside diameter, inside diameter and bolt pattern using a compass on 1/16-inch-thick oil resistant cork gasket material. I used a pair of scissors and a paper punch to cut out the gasket and bolt holes. I also used the F5 felt that I ordered from McMaster-Carr to make the chock stem felt washer. The chock stem spring is the same as the intake valve spring. The gasket for the air cleaner bracket to head is the same gasket used on the regular 3 HP Type E mixer body. I repaired the pinholes in the bottom of the oil cup with JB Weld and gas tank sealer.

I made the crankcase cover gasket and the ventilator cap gasket from 1/32-inch high-density gasket material. The regular 3 HP type E crankcase cover gasket can be used as a pattern. Using the crankcase cover, the side oil flanges were added to the gasket layout.

Main bearing dust shield
The main bearing caps have an oil slot on the top of the cap in order for more oil to lubricate the bearings. The casting number on the bearing cap is E 86 R. The crankcase cover is flared out on both sides, which allows oil to drain into the top of the main bearing caps.

The outer edges of the main bearings are protected from dust by the dust shields.

The impulse magneto
An impulse magneto along with a spark plug is used on the EP engine. The timing is set up the same way as on a regular Type E engine. Align the punch mark on the magneto gear with the punch mark on the cam gear so that the punch mark on the crankshaft gear lines up with another punch mark on the cam gear.

Making a new muffler 
The EP muffler is similar to the John Deere BR tractor muffler. They both have the same top turnout.

I made the muffler using 3-inch outside diameter by 18 gauge thin-wall tubing cut to 23 inches long. The muffler top was turned on a lathe for a snug fit inside the 3-inch tubing (approximately 2.870 inches). The bottom insert with the 1-1/4-inch pipe threads was also turned on the lathe. I assembled both ends into the 3-inch tubing using 95/5 silver solder.

The flanged pulley
The EP pulley is flanged. The pulley size is 7 inches in diameter and 5-1/2 inches wide with a 3/4-inch flange.

Contact Richard Dechant at 20453 Route 322, Corsica, PA 15829 •  edechant@atlanticbb.net