3-HOLE FUEL PUMP FOR JOHN DEERE RE20042

The RE20042 3-hole fuel pump is a mechanical feed pump designed for the diesel fuel system of John Deere tractors. It replaces part numbers AR89956, RE12386, RE20042, and RE27848. Due to its 3-hole mounting and identification dimensions, this part must be carefully verified before ordering, particularly for John Deere Series 40, 50, and 55 applications.

Restoring the diesel fuel supply to the injection pump

This pump draws fuel from the tank and delivers it to the injection pump at a steady flow rate. In a diesel engine, it operates upstream of the injection system and contributes to starting, stable engine speed, and continuous fuel supply under load. This part is a mechanical diaphragm pump designed for a 3-hole mounting.

When the fuel pump fails, the most common symptoms are difficult starting, stalling, loss of RPM, lack of power, or air in the fuel system. A diesel leak around the pump may also require its replacement.

Useful reference points for identifying the correct part

The first thing to check is the 3-hole mounting. Next, verify the mounting hole center distances and the effective dimensions to compare with the part currently installed: 52 mm vertical center distance, 34 mm horizontal center distance, and a lever length of 23 mm. Comparing the replaced part numbers is equally important: AR89956, RE12386, RE20042, and RE27848.

On this type of pump, even a few millimeters of deviation in the mounting or lever is enough to prevent proper installation. If your tractor has previously been retrofitted, compare the removed pump, its markings, and its dimensions before confirming the replacement.

Affected John Deere Models

This fuel pump is used on several John Deere tractors, with applications found in the 40, 50, and 55 series. These include, in particular, the 4440 and 4640 (depending on the model number), as well as the 4050E, 4250, 4450, 4650, 4055, 4255, 4455, and 4755, depending on the variant. For some tractors, compatibility depends on the serial number or the country of destination.

This point warrants careful verification when the same model is available in European, U.S., or Mexican versions. Cross-referencing the part number being replaced with the mounting dimensions helps avoid confusion between two pumps that look similar but differ in their mounting configuration.

Checks to Perform During Replacement

During installation, it is helpful to check the condition of the hoses and seals, as well as the cleanliness of the fuel system. A clogged diesel filter or a dirty fuel tank can disrupt fuel delivery and complicate diagnosis. After installation, bleeding the system according to the machine’s procedure helps remove air from the fuel system before putting it back into service.

To select this pump, consider three simple factors: replacement part numbers, the 3-hole mounting pattern, and installation dimensions. This verification remains the best method for identifying the correct part before working on your tractor.

Dimensions and Technical Specifications

• 52 mm
• 34 mm
• Length = 23 mm

Compatibility by Brand and Series

John Deere

• 4440 (Europe) starting with serial no. 068359
• 4440 (USA) starting with serial no. 068359
• 4640 starting with No. 068690
• 4050E
• 4250
• 4450
• 4650
• 4055
• 4255
• 4455 (Mexico - 6076T engine)
• 4455 (USA)
• 4755 (up to No. 165526)

FAQ — Frequently Asked Questions

What is the purpose of this 3-hole fuel pump on a John Deere diesel engine?

It is used to deliver diesel fuel from the tank to the injection pump at a steady flow rate. In this type of system, it is located upstream of the injection system and helps ensure a continuous fuel supply to the engine. This part is mounted on a 3-hole base.

How can I identify the RE20042 pump before ordering?

The surest way is to compare the part number being replaced and the mounting dimensions. This pump corresponds to part numbers AR89956, RE12386, RE20042, and RE27848, with a 3-hole mounting, a vertical center-to-center distance of 52 mm, a horizontal center-to-center distance of 34 mm, and a lever length of 23 mm.

Is this pump compatible with John Deere 4440 and 4640 models?

Yes, it is suitable for John Deere 4440 (Europe) models starting with serial number 068359, 4440 (USA) models starting with serial number 068359, and 4640 models starting with serial number 068690. Since these models may have undergone previous part replacements, be sure to also compare the current part number and dimensions.

What signs might indicate that the fuel pump needs to be replaced?

Difficult starts, engine stalling, reduced engine speed, lack of power, air bubbles in the fuel system, or a diesel fuel leak are common signs. Before putting the machine back into service, also check the hoses, the filter, and bleed the fuel system according to the machine’s procedure.

Original replacement part numbers and brands are provided for comparison purposes only. This does not imply that they are original parts.