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Discussion Starter · #1 · (Edited)
I have read various opinions for how to properly break in a new car. Many say take it easy, others say drive it hard, WOT. :eek: I read a page from someone telling about how to break in a motor cycle. He explained that the rings need to seat for optimal compression and thus power. I mentioned this to an ASE certified mechanic who formally told me to baby it, and he said the article is correct, BUT it is extremely important to make sure the engine is fully warm before getting on it, but after it is warm use short bursts of WOT.

With the CVT-2 telling the engine to redline when you apply some pressure to the gas peddle, I assume most caliber drivers are getting WOT new engine break-ins without realizing it. I also assume Dodge realizes this as well.:rolleyes:

Any ideas, suggestions, recommendations?

What is everyone else doing to break in their engine?
 

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I agree........mixed driving would be the proper thing to do.
 

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Discussion Starter · #4 ·
I found the follwoing at another site, any thought or corrections?

I have operated a mechanic shop for 30+ years and have rebuilt
numerous Nissan engines as well as engines on other vehicles. I have
extensive information about manual transmissions and clutches on my
site

In answer to your question: Yes, proper break-in is VERY critical to
making your engine last as long as it should. When an engine is brand
new (or freshly rebuilt) the cylnder walls and piston rings have not
yet "worn in" to fit each other.
Before you assemble an engine you hone the cylinders to create a
"crosshatch" pattern. These fine "scratches" in the cylinder wall
hold oil while and providing a slightly abrasive surface against the
piston rings. The piston rings when new have a dull (slightly rough)
finish to them.
As the motor "breaks in" the slightly rough piston rings and the
slightly rough cylinder walls polish each other to provide a tight
seal on the combustion chamber. If this polishing is not accomplished
properly, you will have excessive blowby gasses from your motor
There are other things that have to "break in" on a new motor, most
notably the valves have to "seat in", but these are not nearly as
critical as the piston ring break-in.

When I build a motor, I follow this strategy:
First, I get it running. I will run it at aboiut 2000 to 2500 RPM for
about 10 to 15 minutes. After that I shut it off and check the oil
and coolant levels one more time.
This step has already been done at the factory on a new car.
The next step is a road test. The worst thing you can do to a new
motor is let it just sit still and idle. The cylinder walls (piston
rings) rely on oil slinging off the crankshaft to lubricate them, so
you want a lot of oil slinging around in there. At idle very ilittle
oil is being sprayed around inside the crankcase.
The second worst thing you could do is to "lug" or "dog" the motor: in
other words put it under so much of a load that it jumps and jerks or
goes below 700 RPM or so.
The third worst thing would be to "hot rod" the motor: going very fast
and doing hard acceleration with it.

The best way to break in a motor is to drive it gently, but under
various conditions. I try to get out on a highway, and go 45 MPH for
awhile, then 55, back to 45, then up to 65, gently accelerating
between those speeds. Speed isn't as important as RPM: Keep the RPM
under 3000-3500 AT ALL TIMES!!!
 

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Until what mileage should we "Keep the RPM
under 3000-3500 AT ALL TIMES!!!" :confused:
 

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I disagree about keeping the RPM's low at all times during break in. Occassional short burst WOT helps the break in process (the manual mentions this). What you don't want to do is hold it at high RPM more than a quick burst. The worst thing one can do to a new engine is bog it down which with a CVT transmission is not easy to do anyways. Towing or starting from a stop on a steep uphill grade would not be good.

Todays engines are machined at much tighter tolerances than years ago. The break in process is not as critical as it once was. Still, don't push the engine hard but do vary the RPM's while driving.
 

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Discussion Starter · #7 ·
Huff said:
I disagree about keeping the RPM's low at all times during break in. Occassional short burst WOT helps the break in process (the manual mentions this). What you don't want to do is hold it at high RPM more than a quick burst. The worst thing one can do to a new engine is bog it down which with a CVT transmission is not easy to do anyways. Towing or starting from a stop on a steep uphill grade would not be good.

Todays engines are machined at much tighter tolerances than years ago. The break in process is not as critical as it once was. Still, don't push the engine hard but do vary the RPM's while driving.
By varry, do you mean 10 minutes, of 30 mph, 10 mintues of 40 mph, 10 minutes, of 50 mph, etc, or up and down in speed a lot more quickly, only holding the same speed for a few seconds?
 

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caliber172 said:
By varry, do you mean 10 minutes, of 30 mph, 10 mintues of 40 mph, 10 minutes, of 50 mph, etc, or up and down in speed a lot more quickly, only holding the same speed for a few seconds?
It's mostly RPM's that need to vary rather than be concerned with speed itself. Driving around town you're already going to vary RPM's. On the highway just vary your speed every 10 minutes or so rather than hold it constant. The main thing on a new engine is not to push it too hard such as driving as fast as you can up a steep mountain grade.
 

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Wot's a WOT? :confused:
 

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Discussion Starter · #11 ·
Huff said:
It's mostly RPM's that need to vary rather than be concerned with speed itself. Driving around town you're already going to vary RPM's. On the highway just vary your speed every 10 minutes or so rather than hold it constant. The main thing on a new engine is not to push it too hard such as driving as fast as you can up a steep mountain grade.
I was thinking that in town driving would accomplish the varrying rpm of the engine, but with town driving it is considered hazzard driving because it causes a constant strain on the engine, or is it mainly because people tend ot drive in town without giving the engine time to warm up then park it?

If one was to drive in town easy for a couple of hours, that would be a good start?
 

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I know a few mechs with Dodge down east and they tell me the same thing...

Follow the owners manual.

Regards
 
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