This is what was explained to me:
The break in proceedure should have you runnng the engine at changing RPMs for the first 10 hrs with NO WOT run for more than 1 minute after the first 5 hrs. RPMs 3000 or lower should be avoided for any length of time. Hrs 10 -20, WOT for no more than 2 minutes at a time. Change the oil after the first 20 hrs. After the first 20 hrs, run it like a scalded dog if you wish. Check the oil regulalry for the first 50 hrs as new engines can use more oil at first.
It's important to note that your engine SHOULD be running within the WOT recommendations (I believe 4600-4800 rpms). If it doesn't you are putting undue load on the engine and the cause of the reduced WOT should be corrected. It could be anything from the wrong prop, a really dirty bottom to serious engine problems.
Barr Marine by EDM wrote:
Break-In
Taking care now to break-in your new Indmar engine is VERY important. When broken in properly, your engine will last longer, run better and require fewer repairs over its lifetime. Your new Indmar engine does not require an elaborate break-in procedure, just a little care and common sense for the first few hours.
Break-in Tips
Always let the engine warm up to normal operating temperature before accelerating.
Avoid fast accelerations and don't carry (or pull) a heavy load during this period.
Check the engine oil frequently. During the first 50 to 100 hours, the engine can use more oil than usual. Maintain oil at proper level but do not overfill.
Vary the boat speed during break-in. Do not run at the same RPM for very long.
Observe gauge readings and check for loose mountings, fittings, nuts, bolts and clamps.
Report any abnormal operation, noises or vibrations to your dealer.
Break-in Steps
1. For the first hour, do not exceed 2000 RPM; vary RPM continuously.
2. For the second hour, do not exceed 3000 RPM.
3. For the next 5 hours, do not exceed 4000 RPM.
After the first 10 hours of operation, take your boat tO the dealer for its first engine oil and filter change and engine checkup. Your dealer is best equipped to check the engine immediately after break-in.
After break-in, your engine may be operated at any RPM within the limits for the engine. Your boat must be fitted with a propeller that will allow the engine to turn between 4400 and 4800 RPM at wide-open throttle with a normal load in the boat.
_________________
Jvalich
http://www.badcock.com'04 FW 288 Vista "Mental Floss"