What fuel:oil ratio after removing oil injection?
 

My Promax 300's have had the oil tank and injection setup blocked off to avoid the gear failure problems.. The previous owner told me he runs 50:1 but to me that seems kinda light on oil..

I sure dont want to run it to light on oil..

I know the oil debate has been beaten into the ground, but all the threads on it are now 4 or 5 years old.. What oil would you recommend?

I am no expert on those 300's, but 50:1 sounds fine, the new synthetic 2-stroke oils are far better than what we used to have.

Cale the SVT Allisons rippin around here on the river all runnin 50-1 mix

Ok cool! I'm just used to seeing 32:1 and higher! Thanks!

Merc reccomends running the 2.5L's at 40-1 with Merc High perf oil. I run Klotz R50 at 40-1 pre-mix never had a lubrication failure. But we are turing 9000rpm+ . I would feel a litte safer at 40-1.

Jeff

I have the promax 300s though, not 2.5's.

I run my 8000+rpm 2.5l at 32:1. I run my 6700rpm 4.0l Johnson V8's at 50:1.

There are some variables you need to consider. If the motors are EFI (I don't think Merc made the Pro Max in a carb model), stock except for the oil injection mods and you will not be running at WOT all the time then 50:1 will be fine.

If the rev limiters have been removed with an aftermarket chip and/or you like to run hard I would recommend 40:1 with a good synthetic like Klotz, Royal Purple, Amsoil etc.. the extra lubrication will help with engine life.

John

If you want the best run this....
http://www.amsoil.com/storefront/ato.aspx

Even at 100:1, its still 3-4 times stronger than any other 50:1 mix out there!

Anybody run Motul 800 2t synthetic ester? My old 2.4's seemed to like it and smelled good also.