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What is your opinion on MotoMan's Break In Procedure?

7K views 18 replies 14 participants last post by  AIR_RAM 
#1 ·
It's almost time to break in my new Hemi & instead of the "easy" break in I did with my 2005 Hemi (which has 257,000 miles), I'm thinking about following MotoMan's "secrets" which are basically "Run it Hard".

I tend to think the owners manual break in procedure was written by lawyers who need to protect the manufacturer. If MotoMan "secrets" are true the manufacturer can't tell us that..

What do you think? Run it hard (while keeping engine temp. normal) or Run it easy and keep it under 55 while varying the speed?

http://www.mototuneusa.com/break_in_secrets.htm
 
#2 ·
I've always said "run em in hard and they run long and strong".

With a couple of proviso's;

1. No bashing the rev limiter
2. No sustained period at constant throttle or constant RPM
3. No high load or hard running when cold (that goes for any engine anytime though!)

Enjoy! :)
 
#6 · (Edited)
On initial startup check for leaks... insure transmission fluid is at correct level... once engine reaches operational temperature... take it out on the road and RUN IT WOT 1st 2nd & 3rd then let off and throw it into neutral... bring it to a stop and run it again WOT 1st 2nd & 3rd and repeat 4-5 times... after that just run it normal.

It’s important you make all this happen within the first 20 minutes...

Why.... PISTON RING SEAL! Your hone marks on your cylinders act as a file on your rings. Under light loads the rings do not pressurize against the inner bore enough to take advantage of the hone marks. The only way to get those rings seated perfectly is to run it at WOT UNDER LOAD...this forces the rings to press up against the inner bore hone marks and file them to a perfect match/seal. In a short period of time the hone marks will lose their sharp edges and their ability to file.... The window is small but very important to the future of that engine. The reason I say let off and throw it into nutral is that the rolling load does not help sealing the cylinders.... You want WOT load for the first few runs...

Engines that are run hard during beak in will ALWAYS run faster burn less oil and be more fuel efficient than those that were broken in lightly. So run it like you stole it for a long happy engine life.

SPEED SAFE, NICK
 
#7 ·
On initial startup check for leaks... insure transmission fluid is at correct level... once engine reaches operational temperature... take it out on the road and RUN IT WOT 1st 2nd & 3rd then let off and throw it into neutral... bring it to a stop and run it again WOT 1st 2nd & 3rd and repeat 4-5 times... after that just run it normal.

It’s important you make all this happen within the first 20 minutes...

Why.... PISTON RING SEAL! Your hone marks on your cylinders act as a file on your rings. Under light loads the rings do not pressurize against the inner bore enough to take advantage of the hone marks. The only way to get those rings seated perfectly is to run it at WOT UNDER LOAD...this forces the rings to press up against the inner bore hone marks and file them to a perfect match/seal. In a short period of time the hone marks will lose their sharp edges and their ability to file.... The window is small but very important to the future of that engine. The reason I say let off and throw it into nutral is that the rolling load does not help sealing the cylinders.... You want WOT load for the first few runs...

Engines that are run hard during beak in will ALWAYS run faster burn less oil and be more fuel efficient than those that were broken in lightly. So run it like you stole it for a long happy engine life.

SPEED SAFE, NICK
+1 good info. Thanks!
 
#8 ·
What happens if you get the truck with 20 or so mi on it? should you still do a hard break in or is it too late?
 
#9 ·
The ridges of a crosshatch in the cylinder are microscopic and are very necessary to exist or oil does not get distributed well and rubbing occurs as well as poor sealing. The oil also must prevent the crosshatching from being worn down. Trying to use the crosshatching as a file and saying after a few miles its worn down is a bit much...

Also the idea of cylinder pressures being "thousands of psi" is absurd
 
#11 ·
I completely agree on breaking in the vehicle like you would drive it normally, varied speeds and cool down cycles all help everything seat the way it should.

I do have a couple concerns about the take it out and run it a WOT the first time you drive it method though. Firstly, modern ring technology has allowed for rings that seat within the first strokes of engine turn over, so long before you ever get your car the rings are already well on their way to being seated.
Secondly, running at WOT before a proper tranny/transfer case/rear end warm up will damage other components in the drive train. I built a monster motor for my Z06 and put a brand new DTE rear diff in the car then immediately ran it on the dyno, the rear end completely disintegrated...
 
#12 ·
I have broken every engine in hard. I have always had strong running engines that never burned oil. Even some engines (like my R6) seemed to be more powerful than other similar R6's. The only thing I attribute to being faster was the hard break in.

I have ALWAYS, with EVERYTHING:

Take it out, 1st gear, WOT to 4-5000 rpms, let off leaving the transmission in gear, I always felt/read this will help get the small metal shaving of the rings sealing out the piston/exhaust better. Do this a couple time, change the oil early (500-1000 miles) and then drive normal.
 
#13 ·
Although everything people are saying in this thread sounds knowledgeable and backed by some facts, I just cant for the life of me picture myself doing 5 WOT runs in a row with like 6 miles on the ODO. First off it is VERY critical as woosch stated that the transmission and differentials are worn in correctly. And I can assure you that 5 sustained WOT runs 1st through 3rd will be assuring everything BUT proper break in for those. To be honest I would rather have my tranny and differentials broke in more properly then my engine. Main reason being is regardless of how a motor is broken in (as per the manual or by the WOT runs), the engine will be reliable for as long as your gonna own the vehicle. That car will be on its 5th owner before any evidence of how that motor was broken in shows up.

You guys can do what you want but when I take delivery of my Overland in a couple months the last thing im gonna be doing is flooring the $hit out of it. Im going to drive relatively easily with VARYING RPM's (that to me is whats key). Always ensure fluids get up to proper operating temp before doing anything crazy.

James
 
#14 ·
Immediately after doing a ring job there's an important and highly specific break-in procedure. Ever seen the movie 'The Gods must be Crazy'? That'll give you an idea of the extreme case!!!
However for a new vehicle, I personally wouldn't stray too far from the recommendations in the owners manual.
 
#15 ·
People act like their new vehicle isn't driven before they get inside. The engine is tested after assembly. The car is brought up to cruising speed at the assembly plant for system checks, left idling for awhile to check for leaks, and then driven on a small course to check for rattles. The its driven into a parking lot, then driven onto some transportation, then driven by the dealer....

The whole floor the thing immediately after you build the engine isn't even applicable to this situation.
 
#17 ·
We have an 04 Durango that I broke in doing the varied RPM/heat cycle method, it has over 200k miles on it and still going strong. Never any oil burning issues, still the original motor, tranny, transfer case, and diffs.

The second key to making any vehicle last is doing all the required service at the right intervals.
 
#18 ·
I recommend reading:

http://www.mototuneusa.com/break_in_secrets.htm

Having said that, make sure you read the WHOLE THING before you get started. What you are looking for is NOT high RPM's. You want lots of load and a very open throttle.

I've been rebuilding & tuning race motorcycles for years (mainly 2-strokes) and have used his technic on all of the engines. Since our bikes get new pistons and rings every 200 miles it is easy to determine which method works best. His method works very well for getting the engine ready for full race conditions very quickly. It also seems to give the best results (i.e., most power) once the engine is ready to race.
 
#19 · (Edited)
My response was aimed at the brake in of a NEW engine... I missed the part that said it was for a new vehicle... BUT I still believe it should be run HARD if you want the best overall performance.

My 2002 4.7L Ram was ALWAYS faster than the average 4.7L Ram. Many felt my truck was a "Factory Freak" because it just outran most 4.7L and with minor bolt ons was nipping at the heels of the HEMI Rams. Topped off with the fact that it always seemed to get great fuel economy when that was the goal, even able to average over 21MPG with mixed city/highway driving over 4 tanks of gas.

I honestly believe it’s because my 4.7L saw 6,000RPMS about 6-7 times a day for 140,000 miles... I ran it hard right out of the stealer ship parking lot and never left off the throttle. I swapped over to full synthetic Mobil 1 at the 500Mile mark and never looked back changing the oil every 3000-4000 miles.

Believe it or not, running an engine hard is GOOD for it! Over revving it, letting the fluids get old or not insuring coolant is topped off is NOT good for it. As long as your fluids are topped off and fresh, run it like you stole it every now and then. Your engine will reward you for it.

SPEED SAFE, NICK
 
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