Breaking in a rebuild

[BV74]

I lost my #4 cylinder on my 2002 175 Eli. So I’m having it rebuilt over the winter. Also new water pump, clean fuel injectors, new reeds and impeller. Now my question is. How do I break in the rebuild? Thanks for any input

[luvdmymerc]

If you're getting any kind of warranty from the folks that are doing the rebuild for you, they will have a break in procedure they'll want you to follow. Traditionally they will ask you to run double oil thru it for the first so many hours, and will have a schedule of how many hours to run it at certain rpm levels. They'll ask you to vary your speed....short bursts at a higher rpm rate, then back down and let it cool off, etc. I have seen many different schedules over the years, all similar, all different. An original Mercury manual for your motor would be awesome to have. If your mechanic or machine shop doesn't have a particular procedure they want you to follow, then I would diffinitely go by the Mercury manual....

[BV74]

Thanks man.. I do have the original manual for it. I’ll roll with that....

[luvdmymerc]

[SilverFox579]

Know your engine isn't an Optimax, but there are some tips in this topic that, in addition to manual recommendations, would apply to all engines (heat cycling is one) - Optimax Engine Break-In

[BV74]