Description:
PP-3917117 CN Cummins Marine Transmission / Gear Oil Cooler
The PP-3917117 CN Cummins Marine Transmission / Gear Oil Cooler is a robust copper-nickel shell-and-tube oil cooler designed to control gearbox oil temperatures on Cummins 5.9L and 8.3L marine diesel platforms.
This unit functions by passing hot transmission oil through the internal tube bundle while raw seawater circulates through the outer shell, efficiently dissipating heat before oil returns to the marine gearbox. Maintaining stable oil temperature is critical for protecting clutch packs, bearings, seals, and gear sets, especially during extended cruising, heavy manoeuvring, or high-load operation.
The CN (copper-nickel) construction provides excellent resistance to salt-water corrosion and electrolysis compared with older copper-brass units. For added protection, the cooler is fitted with sacrificial pencil zinc anodes, helping extend service life in demanding marine environments.
Manufactured to OEM dimensional and flow specifications, the 3917117 CN is a direct-fit replacement for Cummins part 3917117. It installs without modification to existing raw-water hoses, oil fittings, or mounting arrangements, making it suitable for routine replacement, refit work, or upgrades from standard-material coolers.
Suits Cummins Marine:
• 6BTA 5.9�L
• 6CTA 8.3�L
• QSB 5.9�L
• QSC 8.3�L
• Cummins marine engines fitted with marine transmission (gearbox) oil cooling circuits
• Commonly used with ZF, Twin Disc, Borg Warner, and Velvet Drive marine gearboxes (application-dependent)
Replaces
• Cummins: 3917117