Installing electric fans in a "puller" configuration with the radiator behind the core support in a VB is challenging due to limited space between the radiator and engine. Proper cooling requires the fans to be mounted on the back side of the radiator to maximize efficiency. This article explains how to achieve optimal cooling using a fan shroud kit and electric fans.
Why Use a Fan Shroud?
Electric fans work more efficiently when installed on the back side of the radiator core. Here’s why:
- Without a shroud, fans only draw air directly in front of them, leaving the rest of the radiator with little airflow.
- A shroud ensures air is pulled through the entire radiator core, improving cooling performance, especially at low speeds.
Fan Shroud Kit Overview
The new fan shroud kit (PIN 57-177509-1) is designed for down-flow radiators in 6-cylinder positions. It includes:
- Two 10" electric fans (1400 CFM each, totaling 2800 CFM).
- Dual relay wiring harness with a wiring diagram.
- Temperature sender to control fan activation.
- Custom-formed aluminum shroud for maximum cooling efficiency.
Available Kits
- 57-177509-1: Aluminum Fan Shroud with Dual Electric Fans (6-cylinder, down-flow radiator).
- 57-177510-1: Aluminum Radiator with Dual Electric Fans (6-cylinder, down-flow radiator).
- 57-177452-1: Aluminum Fan Shroud for Dual Electric Fans (6-cylinder, down-flow radiator).
- 57-132134-1: Radiator Relocation Kit (to 6-cylinder position).
Tools Needed
- 1/2" wrench
- 9/16" wrench
- 7/8" wrench
- Drill with 1/8" drill bit
- Cutters and crimpers
- Pop rivet gun
Estimated Installation Time: 4 hours
Step-by-Step Installation Guide
Fan Shroud and Fan Kit Assembly
- Assemble the shroud kit before installation.
- Secure the 10" fans to the aluminum shroud using button-head 3/16" rivets for a polished look.
Shroud Attachment
- Align the shroud slots with the radiator mounting bolts.
- Drill through the side rails using a 1/8" drill bit, avoiding the radiator core.
- Use supplied hardware to attach the shroud to the radiator.
Radiator and Fan Installation
- Install the radiator and fan shroud assembly from the front (grille) side of the core support.
- Adjust the radiator to the rear of the core support, leaving approximately 1/4" clearance.
Wiring the Fans
- Connect each fan's red wire to the blue wires in the harness.
- Connect both black fan wires to a body ground using the supplied lug.
- Attach the large red wire from the harness to a constant 12-volt fused power source.
Temperature Sender and Additional Connections
- Install the temperature sender in the intake manifold for accurate readings.
- Wire the green harness wire to the sender and a body ground.
- If air conditioning is present, connect the gray wire to the AC clutch wire. If not, this wire is unused.
- Connect the yellow wire to a 12-volt ignition-on source.
Final Tips
- Ensure all connections are secure and properly grounded.
- Use the toggle switch or temperature sender to control fan operation.
- Enjoy a cooler running engine and improved AC efficiency!