moving from 496 mag to 496 HO
10-16-2017 | 02:09 PM
#1
Thread Starter
Registered
Joined: Apr 2017
Posts: 31
Likes: 14
moving from 496 mag to 496 HO
Hello,
I have a Baja 275 and the engine blew on me late this season (496 mag). I have ordered and will be installing a new 496 HO. I was wondering if anyone can chime in on what type of performance increases I can expect? Increase in speed? Acceleration? Is there a difference in sound?
Thanks for your input!
I have a Baja 275 and the engine blew on me late this season (496 mag). I have ordered and will be installing a new 496 HO. I was wondering if anyone can chime in on what type of performance increases I can expect? Increase in speed? Acceleration? Is there a difference in sound?
Thanks for your input!
05-01-2018 | 02:24 PM
#10
Registered
Joined: Oct 2016
Posts: 10
Likes: 0
Same prop as I run on my 275 with HO. What I've seen on Merc's break in:
20-Hour Break-In Period
IMPORTANT: The first 20 hours of operation is the engine break-in period. Correct break-in is essential to obtain minimum oil consumption and maximum engine performance. During this break-in period, the following rules must be observed:
Do NOT operate below 1500 rpm for extended periods of time for the first 10 hours. Shift into gear as soon as possible after starting and advance the throttle above 1500 rpm if conditions permit safe operation.
Do NOT operate at one speed consistently for extended periods.
Do not exceed 3/4 throttle during the first 10 hours. During the next 10 hours, occasional operation at full throttle is permissible (5 minutes at a time maximum).
Avoid full throttle acceleration from IDLE speed.
Do NOT operate at full throttle until the engine reaches normal operating temperature.
Frequently check engine oil level. Add oil as needed. It is normal for oil consumption to be high during the break-in period.
After Break-In Period
To help extend the life of your Mercury MerCruiser power package, the following recommendations should be considered;
Ensure that propeller allows the engine to operate at or near the top of the specified WOT rpm range (Refer to Specifications and Maintenance) when at full throttle with a normal boat load.
Operation at 3/4 throttle setting or lower is recommended. Refrain from prolonged operation at WOT rpm.
Change the oil and oil filter. Refer to Specifications and Maintenance.
20-Hour Break-In Period
IMPORTANT: The first 20 hours of operation is the engine break-in period. Correct break-in is essential to obtain minimum oil consumption and maximum engine performance. During this break-in period, the following rules must be observed:
Do NOT operate below 1500 rpm for extended periods of time for the first 10 hours. Shift into gear as soon as possible after starting and advance the throttle above 1500 rpm if conditions permit safe operation.
Do NOT operate at one speed consistently for extended periods.
Do not exceed 3/4 throttle during the first 10 hours. During the next 10 hours, occasional operation at full throttle is permissible (5 minutes at a time maximum).
Avoid full throttle acceleration from IDLE speed.
Do NOT operate at full throttle until the engine reaches normal operating temperature.
Frequently check engine oil level. Add oil as needed. It is normal for oil consumption to be high during the break-in period.
After Break-In Period
To help extend the life of your Mercury MerCruiser power package, the following recommendations should be considered;
Ensure that propeller allows the engine to operate at or near the top of the specified WOT rpm range (Refer to Specifications and Maintenance) when at full throttle with a normal boat load.
Operation at 3/4 throttle setting or lower is recommended. Refrain from prolonged operation at WOT rpm.
Change the oil and oil filter. Refer to Specifications and Maintenance.
