Engine Break-In; Warm-Up Recommendation; Throttle Recommendation - BRP Johnson 4HP Service Manual

ENGINE BREAK-IN

The first 10 hours are critically important to ensure correct
running of either a brand new motor or a motor that has been
reconditioned or rebuilt. How the motor is operated during
this time will have direct bearing on its life span and long-
term durability.
Break-in period: 10 hours

Warm-Up Recommendation

Allow sufficient idling time (more than 5 minutes) for the
engine to warm up after cold engine starting.

Throttle Recommendation

NOTE:
Avoid maintaining a constant engine speed for an extended
period at any time during the engine break-in by varying the
throttle position occasionally.
1. FIRST 2 HOURS
For first 15 minutes, operate the engine in-gear at idling
speed.
During the remaining 1 hour and 45 minutes, operate the
engine in-gear at less than 1/2 (half) throttle (3000 r/min).
NOTE:
The throttle may be briefly opened beyond the recommended
setting to plane the boat, but must be reduced to the recom-
mended setting immediately after planing.
2. NEXT 1 HOUR
Operate the engine in-gear at less than 3/4 (three-quar-
ter) throttle (4000 r/min).
3. LAST 7 HOURS
Operate the engine in-gear at desired engine speed.
However, do not operate continuously at full throttle for
more than 5 minutes.
GENERAL INFORMATION
ENGINE BREAK-IN
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