View Full Version : Engine Break In Procedure

Webb Sledge
05-26-2005, 12:23 AM
I don't know if anyone is in the process of breaking in an engine right now, but I have seen questions and disagreements on this a while back, so I dug up my break in procedure written for by the Triumph mechanic I work for. Hopefully it'll help someone.

LINK TO ENGINE BREAK IN PROCEDURE SHEET (https://img268.echo.cx/img268/3126/breakinprocedure3xy.jpg)

05-26-2005, 04:28 AM
Hi Webb,

You're link doesn't seem to be working.

Hope to see it soon!


05-26-2005, 08:31 AM
Hey Webb,
I'd agree with all except for the 1,000 mile "no over 3,000 rpm & under 55mph". These limits are way over cautious. The most important part of new engine break in is the first 30 minutes when the cam seats. After that the rest is mostly for the rings. What is important is not to labor the motor with high loads at low rpm's.

I'm not suggesting taking it to a race track out of the box but by 500 miles you should be able to drive normaly (normal for me is not normal ). If your going to throw a rod at 500 miles you'll probably throw it at 1,000 miles of break in.

The rest of the list is pretty much normal maintenance, not just for break in.I think alot of this is "mechanics insurance" to make sure the customer doesn't pick up a fresh motor & head for the auto-cross.
P.S. His handwritting is almost as bad as mine /ubbthreads/images/graemlins/laugh.gif

05-26-2005, 09:13 AM
I was told by my engine guy that after the cam breakin (as described above), you should "drive it like you normally do" He's worked exclusively on Triumph's since 1976 so I'd say he's knows a few things. With all that said, I'm still going to be a little easy on it until about 1000 miles. I do think that "not over 3000 rpms" is a bit excessive though.


05-26-2005, 11:40 AM
Sounds like the pretty standard list. The 3,000 rpm thing is just an old mechanic thing. I don't think many do it anymore, but thats how my dad was taught back in the late 60s, and its how I do it.

05-26-2005, 02:06 PM
What gets me is all engine rebuilders have their own little tricks to "break in" an engine, but I have never seen any guidelines from a car manufacturer. OE engines usually last 100,000 miles or more before needing a rebuild. I would find it VERY hard to believe they break in an engine before selling a car. I'm not saying you shouldn't break one in, just kinda makes you wonder. /ubbthreads/images/graemlins/grin.gif

05-26-2005, 05:52 PM
For cam seating I sit the engine at 2400 rpm for 25 minutes. Let the engine cool for 30 minutes, then 2800 rpm for 15 minutes. Should have broke in after that.

05-26-2005, 06:18 PM
What about the break in for a fresh bottom end only?

Geo Hahn
05-26-2005, 06:21 PM
...I have never seen any guidelines from a car manufacturer...

[/ QUOTE ]

The Lotus Elise has some very specific limits... new owners look for excuses to put miles on them so they can get past that point and open it up. No cheating either as when it goes in for it's first check-up they read the computer to see if you got carried away.

05-26-2005, 08:45 PM
My procedure is turn it on...get it in gear and FLOOR IT.

Oh wait...that's the "break engine procedure." /ubbthreads/images/graemlins/wink.gif