---
kind: "section"
citation: "46 C.F.R. § 119.420"
title: "46"
number: "119.420"
heading: "Engine cooling."
url: "https://uscodex.org/cfr/46/119.420"
---

# §119.420. Engine cooling.

- (a) Except as otherwise provided in [paragraph (b)](#b) of this section, all engines must be water cooled and meet the requirements of this paragraph.
  - (1) The engine head, block, and exhaust manifold must be water jacketed and cooled by water from a pump that operates whenever the engine is operating.
  - (2) A suitable hull strainer must be installed in the circulating raw water intake line of an engine cooling water system.
  - (3) A closed fresh water system may be used to cool the engine.
- (b) A propulsion or auxiliary diesel engine may be air cooled or employ an air cooled jacket water radiator when:
  - (1) Installed on an open deck and sufficient ventilation for machinery cooling is available; or
  - (2) Installed in an enclosed or partially enclosed space for which ventilation for machinery cooling that complies with the requirement of [§ 119.465(b)](/cfr/46/119.465.md?p=b) of this part is provided, and other necessary safeguards are taken so as not to endanger the vessel.

## Notes

### Authority

Authority: 46 U.S.C. 2103, 3306; E.O. 12234, 45 FR 58801, 3 CFR, 1980 Comp., p. 277; DHS Delegation No. 00170.1, Revision No. 01.3.

### Source

Source: CGD 85-080, 61 FR 922, Jan. 10, 1996, unless otherwise noted.