Cummins built motor question

twest42271

New member
Sep 7, 2012
46
0
0
east tn
Hey guys i know it's not a duramax question. But I've got a buddy who just Purchased a motor from industrial injection and he is wondering how long does he need to b easy on it or any at all. Thanks
 

adeso

wait, what?
May 30, 2011
1,569
0
36
Minot, ND
Take it easy for the first couple hundred miles, change the oil then if it is done right it won't matter. I like to go easy for that first little bit to let everything set in and if something is bad wrong good chance you can ID it before you put the power to it, but if it is done right 2-300 miles oil change then ramp it up is what I did. Since it isn't bad to re torque the HS I would have done that if I owned a I-6

edit, the first start I only high idled it up to operating temp then let it cool down over night to get a nice easy heat cycle on it and let everything set good
 

juddski88

Freedom Diesel
Jul 1, 2008
4,655
120
63
Chesterfield, Mass.
I'd rather make power and not have blowby, so I warm it to operating temp, go through and check all fluids, and go out and break it in. Cylinder pressure seats the rings ;)
 

elliottw

Member
Jan 23, 2013
396
4
13
ND
I'd rather make power and not have blowby, so I warm it to operating temp, go through and check all fluids, and go out and break it in. Cylinder pressure seats the rings ;)

x2 on rebuilds I prelube the engine assuming it hasn't been already, then fire it up for 30 seconds. Let it cool for 30 minutes. Start it again, let it warm up a couple minutes then take it for a short drive, allowing it to warm up a little. Let it cool for an hour. Then I start it for the last time and get out on the road. I put the engine under a load to seat the rings, let the engine decelerate under its own power too. I don't abuse the engine(flog on it) but smoothly apply the power. Has worked great for me! I change the oil after the first 20-30 miles then again at 1000.
 

adeso

wait, what?
May 30, 2011
1,569
0
36
Minot, ND
Also, don't want to hold any RPM for a long time (like taking it on a trip with the cruise on) I think I locked mine into second and would take it from idle to 3500 RPM a bunch of times after the first heat cycle
 

J Spruill

bringer of truth
Mar 30, 2008
770
0
16
personally id call II and ask them how they want the motor broke in. when i put a new motor in a always go with how my builder likes. usually its start run long enough to check all fluids, short test drive ,recheck then beat the crap out of it...