Anyone see any reason why i couldn't leave the break in oil with 10 hours on it in the motor over the winter months? Or should i change it before hand?

Change it. You don't want all the byproducts, ie. acids and what not sitting in that oil winter, even though it is only 10 hours or so.

Change it now,,,, not because its break in oil,,,, but it has contaminates in it from combustion.

its cheap quick and easy,,, no reason to skimp

Do change it!

Put in some 15W-50 M-1...or Merc 25W-40.

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What do you think of the Brad Penn racing 20-50, that's what the engine builder gave me?

It is very stout...high in anti-wear additive ZDDP.

Most outstanding conventional oil!

Is this a green colored oil like Penn's 30wt?

Yes it is.

How would you compare it to Mobil 15W-50 silver cap?

My recently rebuilt 1952 graymarine engine has not even 5 hours on it and it's time to put it up for winter. Should I change it with more break in oil or put regular 30W in ? I think it should have more time with the break in oil. Not sure what to do.

I ran into that the end of last season with only about 3 hrs on new builds. I ended up getting out on the water late this year however started out with the same oil and changed after about 10-12 hrs total. I felt a little guilty but honest. IMO if you’re gonna do it now OR in spring then do two changes back to back with inexpensive oil while bringing up to temp each time.

That’s what I did this summer/fall with auto value house brand (suppose to be valvoline). Biggest and best oil filter is important!

I don't have a problem changing in now and again in the spring but what I'm asking is should I replace with break in oil again each time till I have more hours on the engine?