December 14, 2021, 08:21 AM
Joe CBreak-in Oil
How long do leave break-in oil in a new engine?
December 14, 2021, 08:28 AM
1320racerI know racers that run break oil all season long.
That said, I have dumped the break in oil once dyno’d and I have keep it in for 25-30 passes which is my typical oil change interval. I’ve also ran engines that were not dyno, with Mobil 1 synthetic from day 1.
Do what your engine builder says and if that’s you, flip a coin and go with it.
December 14, 2021, 09:51 AM
EmanI drain the oil I start the motor on after cam break in, change the filter and put the oil I want to run in.
December 14, 2021, 10:50 AM
Bob DenikerI run the oil that I intend to run in it, when it's new. Engines don't wear in, they wear out.
December 14, 2021, 12:30 PM
Goob10-25 runs
December 14, 2021, 12:38 PM
TOP38I have done my own stuff for a long time and can say this, using specific break in oil vs not doesn't seam to make a difference that I have noticed on the time slips or crank case vacuum. I will say this though, during the first start up after a freshen up or new motor, once it's up to operating temp, load the motor! This is what seats the rings. If you let it idle too much it can negatively effect the ring seat in process.
Unless your building a comp or PS motor and looking for every single HP, which BTW is way more involved with just break in oil, for us bracket folks, it's not a make or break deal.
December 14, 2021, 07:57 PM
adv ET 266Oil is cheap. I’d never make any power on the first oil fill, after the Eng has been apart. Put 2-3 good heat cycles on it and dump it and the filter. After that, run your normal oil at your normal interval