Baywindow Bus Alternator Cooling Pipe - 1968-74 - Type 4 Engines

Alternators fitted to early Type 4 engines rely on a dedicated cooling duct to stop them from overheating, and this rubber cooling elbow is the key piece that makes the system work properly. It fits between the engine tinware and the alternator, sealing the gap and directing a steady supply of cooling air straight into the alternator’s oval outlet.

On Baywindow buses, the alternator sits in a hot, enclosed engine bay. Without a good seal and correct airflow, alternator temperatures rise quickly—leading to weak charging, voltage regulator issues, cooked windings, and premature bearing wear. This elbow prevents that by ensuring the alternator receives the cooling air it was designed to have, even during slow traffic, hot days, or long climbs.

Why it needs replacing

Original elbows were often made from poor-quality rubber. After years of heat cycles, oil mist, and vibration they typically become hard, brittle, and cracked, or simply tear at the ends. Once that happens, cooling air leaks away and the alternator runs hotter than it should. Replacing the elbow restores the factory airflow path and helps protect your charging system from heat-related failure.

How it works

• The engine fan produces a high volume of cooling air.

• The tinware forms a controlled airflow route.

• This rubber elbow connects the tinware outlet to the alternator inlet (oval port).

• The alternator’s internal fan then pulls that air through the alternator body, cooling the stator/rectifier area and pushing heat out.

Features

• High quality reproduction rubber elbow for long service life

• Ensures optimal airflow and cooling efficiency

• Designed for alternators with oval outlet

• Correct fit for Type 4 55 amp alternators on early Baywindow applications

Fitting notes and related parts

• Does Not Include Clamp

• Fits between alternator and tinware (cooling duct connection)

• Check your alternator outlet shape: oval outlet required

• Inspect tinware edges for distortion/rust—poor tinware alignment can prevent a good seal

• If your alternator ducting is incomplete, you may also need the matching metal/plastic duct pieces and clamps (where applicable)

Vehicle / Engine compatibility

For use on Baywindow Buses with Type 4 engines and 55 amp alternators built before July 1974.

Engine codes:

• CA engines up to 1972

• AP engines up to 1974

• GE engines (all years)