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-   -   RPM During Engine Break-In (http://www.wranglerforum.com/f202/rpm-during-engine-break-in-441561.html)

TexasBob 12-17-2013 07:55 AM

RPM During Engine Break-In
 
The manual states that brief wide open throttle periods are beneficial to a good break-in and that you can go up to about 55mph during the first 300 miles, however it does not mention anything about engine speed. 4th gear wide open throttle has the rpms pretty low, not even going above 3 or much above 3k.

After truly warming up the engine oil (15 minutes of moderate driving), is there any benefit to taking the car higher in the rpm range (say in 2nd or 3rd gear) during break-in? Is it safe during break-in to carefully bring the car up to redline and let it engine brake to seat the rings? I guess I'm confused about engine "load" versus engine "speed" with regards to seating piston rings.

If anyone has some insight I would really appreciate it. First time wrangler owner and I want to do everything to lessen the chance of developing an oil burner!

Mr Mac 12-17-2013 08:05 AM

Varying engine speeds help the break-in process and every once in a while, when you leave a stop sign, you can run the engine speed up to something just short of redline to help seat everything nice and tight.

demarpaint 12-17-2013 08:12 AM

Getting a warmed up new engine under load running up and down hills is very good for it. A little engine breaking coming down a hill is good to seat the rings.

TexasBob 12-17-2013 08:26 AM

Quote:

Originally Posted by Mr Mac (Post 6821001)
Varying engine speeds help the break-in process and every once in a while, when you leave a stop sign, you can run the engine speed up to something just short of redline to help seat everything nice and tight.


Thank you sir

TexasBob 12-17-2013 08:27 AM

Quote:

Originally Posted by demarpaint (Post 6821105)
Getting a warmed up new engine under load running up and down hills is very good for it. A little engine breaking coming down a hill is good to seat the rings.


That sounds good I've been trying to engine brake it like that but weary of the high rpms. Ok to keep it higher in the rpm band like 4-5.5k going down hills?

demarpaint 12-17-2013 08:37 AM

Quote:

Originally Posted by TexasBob (Post 6821337)
That sounds good I've been trying to engine brake it like that but weary of the high rpms. Ok to keep it higher in the rpm band like 4-5.5k going down hills?

I'd keep it to about 4,000 rpms going down hill, and do it briefly, but frequently. Going up hill you can briefly push it to a little under red line. It doesn't take that many miles to do it, I'd say 500 miles or less and you're done. That's how I break mine in, and have been fortunate never to own an oil burner that I broke in.

Google breaking in a new engine, there's lots of good articles on it.

TexasBob 12-17-2013 09:26 AM

Quote:

Originally Posted by demarpaint (Post 6821521)
I'd keep it to about 4,000 rpms going down hill, and do it briefly, but frequently. Going up hill you can briefly push it to a little under red line. It doesn't take that many miles to do it, I'd say 500 miles or less and you're done. That's how I break mine in, and have been fortunate never to own an oil burner that I broke in.

Google breaking in a new engine, there's lots of good articles on it.


Exactly what I was looking for! Much appreciated

demarpaint 12-17-2013 09:28 AM

Quote:

Originally Posted by TexasBob (Post 6822521)
Exactly what I was looking for! Much appreciated

No problem. I've been successful with it, have a friend who builds engines and he does it pretty much the same way. Enjoy your new ride, and drive it in good health!!!!!

derf 12-17-2013 10:06 AM

Decent write up here:

New Engine Break-in Procedure

Blastek 12-17-2013 10:57 AM

The engine is already broken in at the factory. After the first 60 miles (where you stick below 50 mph - probably to ensure that you don't kill yourself if someone forgot to tighten a bolt) drive normally. Just don't tow.

Any notion that you have a significant impact on the engine life is just a placebo effect. Tolerances and materials are much better than they used to be, so no break-in is required.

derf 12-17-2013 11:00 AM

Quote:

Originally Posted by Blastek (Post 6824497)
The engine is already broken in at the factory. After the first 60 miles (where you stick below 50 mph - probably to ensure that you don't kill yourself if someone forgot to tighten a bolt) drive normally. Just don't tow.

Any notion that you have a significant impact on the engine life is just a placebo effect. Tolerances and materials are much better than they used to be, so no break-in is required.

Every new engine requires a break in period. Modern materials and designs don't change that.

Blastek 12-17-2013 11:06 AM

Quote:

Originally Posted by derf (Post 6824569)
Every new engine requires a break in period. Modern materials and designs don't change that.

Correct. The engine is broken in at the factory before it's even dumped into the Jeep. The combined drivetrain should be treated with a little respect to ensure it's all in order. But, there's no need for a long break in. It says it right there in the manual.

COStrider 12-17-2013 11:35 AM

Quote:

Originally Posted by Blastek (Post 6824649)
Correct. The engine is broken in at the factory before it's even dumped into the Jeep. The combined drivetrain should be treated with a little respect to ensure it's all in order. But, there's no need for a long break in. It says it right there in the manual.

Where's tour proof that engines are broken in at the factory. I'd wager they test run them for trouble shooting. They are not broken by a test run.

COStrider 12-17-2013 12:57 PM

http://www.examiner.com/article/how-...k-a-new-engine

Old Dogger 12-17-2013 01:06 PM

Just break it in the way your manual recommends, and you will be good to go........:D

derf 12-17-2013 03:34 PM

Quote:

Originally Posted by Blastek (Post 6824649)
Correct. The engine is broken in at the factory before it's even dumped into the Jeep. The combined drivetrain should be treated with a little respect to ensure it's all in order. But, there's no need for a long break in. It says it right there in the manual.

They don't do a full proper break in of the engine at the factory. Putting that many hours on an engine just isn't cost effective for a mass produced product.

You need to do a proper break in when you drive it off the showroom floor.

COStrider 12-17-2013 03:36 PM

Quote:

Originally Posted by derf (Post 6829073)
They don't do a full proper break in of the engine at the factory. Putting that many hours on an engine just isn't cost effective for a mass produced product. You need to do a proper break in when you drive it off the showroom floor.

That's what I'm thinking too but I'm not privy to any concrete info. Would love to know though!

derf 12-17-2013 03:47 PM

Quote:

Originally Posted by COStrider (Post 6829105)
That's what I'm thinking too but I'm not privy to any concrete info. Would love to know though!

I've seen some evidence of what actually happens at a factory but it's second hand information so take it with a grain of salt.

The factory builds the engine, on a mostly automated assembly line. They get pretty consistent build quality this way since machines are doing and checking everything at the same time.

Once the engine is mostly assembled they put it on a test stand. They hook up hoses for the water and oil cooler if needed. They then attach it to something that drives the crank. This spins the crank which drives all the accessories and the oil pump, water pump, etc. They check air flow (since an engine is really just an air pump), fluid flow and pressure, and check for leaks. They don't actually run the engine by putting fuel in it and firing it up.

When it passes checks it's put in line to be dropped into a vehicle.

Once the vehicle is built and all the fluids (oil, coolant, fuel) are added, it is fired up and they run the entire vehicle on a rolling dyno for a few minutes. This is the first time the engine is driving itself. They call this a "break in" which is partially true. But it's also the validation process that every vehicle goes through before it's sent out the door.

When it's delivered to the dealership, you have the first few miles worth of initial break in done. But you still need to do a real full break in if you want it to run the best.

One of the reasons they don't suggest full throttle acceleration runs is for legal liability. The first joe sixpack who gets into an accident while doing a full acceleration run will sue the hell out of the manfuacturer. So they give you guidelines that will lean towards the correct break in procedure without exposing themselves to too much legal liability.

RoadiJeff 12-18-2013 12:09 AM

I used to work in a Chrysler assembly plant. I was the first person to start the vehicle and drive it off the main line. I drove it straight to a roll test area where an inspector ran it through a series of tests for about 2 minutes at speeds up to 60 mph. It was nowhere near enough time to break-in a new engine, just enough time to verify that everything was operating normally.

I would imagine the setup at the Wrangler assembly plant is about the same.

COStrider 12-18-2013 12:56 AM

Quote:

Originally Posted by RoadiJeff (Post 6839625)
I used to work in a Chrysler assembly plant. I was the first person to start the vehicle and drive it off the main line. I drove it straight to a roll test area where an inspector ran it through a series of tests for about 2 minutes at speeds up to 60 mph. It was nowhere near enough time to break-in a new engine, just enough time to verify that everything was operating normally. I would imagine the setup at the Wrangler assembly plant is about the same.

That's some great first hand info right there. Thanks for sharing!

michaeldc46 12-18-2013 08:35 AM

Moderate manifold pressure and normal running RPM
 
Run the new engine at moderate acceleration and normal cruise RPM - this is to seat the rings properly, which is the main "wear" item to break in with a new engine. There is NO need to go to much higher RPM than you would normally use for everyday use .........however there is a need to accelerate moderately during the break in process. If you do not accelerate modestly during break in the rings will NOT seat properly and you may have compression and oil consumption issues later on. The prior posted article about motorcycle engine break in explains this very well.
(This is the exact process used to break in piston aircraft engines - run up to 75% power at cruise RPM, cool down and repeat for longer duration a few times - this is done after all potential leaks and loose bolts are thoroughly gone over as is done in the Jeep plant)

derf 12-18-2013 10:09 AM

Quote:

Originally Posted by RoadiJeff (Post 6839625)
I used to work in a Chrysler assembly plant. I was the first person to start the vehicle and drive it off the main line. I drove it straight to a roll test area where an inspector ran it through a series of tests for about 2 minutes at speeds up to 60 mph. It was nowhere near enough time to break-in a new engine, just enough time to verify that everything was operating normally.

I would imagine the setup at the Wrangler assembly plant is about the same.

I'd be surprised if that wasn't what every mass produced car goes through.

The only time I've seen anything different was for exotic sports cars and luxury cars. When you spend 6 figures or more on a car you expect it to be perfect and they can budget the time and resources to fully test and break in the car for you.

When you spend $30-50K on a car, there just isn't room in the budget to seriously test each one beyond a quick roll test. You have to do a basic "do the important things work" test but anything beyond that just isn't cost effective.

Old Dogger 12-18-2013 10:28 AM

How much the engine is, or is not broken in when we receive it, is obviously debatable, per all the above comments.

First of all, there really is more to breaking in a new vehicle, besides just the engine. Basically, everything is new and on the tight side. Plus take it somewhat easy for a while on you brakes, so you don't glaze the brake pads.

As for the engine, leave the conventional oil in it to help seat in the rings.
Drive it at different RPM ranges, like the owners manual recommends. Occasionally 1/2 to full throttle for a short duration is a plus.

After 300 miles, or so, drive it like you just stole it.......:thumb:

Xena1 12-18-2013 05:46 PM

NO engine can be "broke in" at the factory. It needs at least 500 miles to fully seat rings. Moderate driving will do the job, but wait until 1000 miles to really goose it.

TexasBob 12-19-2013 09:16 AM

Thank you so much for the replies everyone. Sounds like the consensus is to get on it every once in awhile but to otherwise drive the car moderately. I've been doing a combination of wot bursts in 3rd and 4th gear at mid rpms (between 2.5 and 4k) and engine braking down hills to help seat the rings (trying to start the engine braking at 4k rpms or slightly below). I'm slowly working the rpms up as the miles climb but not going nuts or hitting the rev limiter haha

derf 12-19-2013 09:34 AM

Just make sure the engine is up to operating temperature before you get on it. Also, just do short bursts.

demarpaint 12-19-2013 10:32 AM

Quote:

Originally Posted by TexasBob (Post 6865665)
Thank you so much for the replies everyone. Sounds like the consensus is to get on it every once in awhile but to otherwise drive the car moderately. I've been doing a combination of wot bursts in 3rd and 4th gear at mid rpms (between 2.5 and 4k) and engine braking down hills to help seat the rings (trying to start the engine braking at 4k rpms or slightly below). I'm slowly working the rpms up as the miles climb but not going nuts or hitting the rev limiter haha

Sounds good, as long as the engine oil is up to temp.

COStrider 12-19-2013 10:37 AM

Quote:

Originally Posted by TexasBob (Post 6865665)
Thank you so much for the replies everyone. Sounds like the consensus is to get on it every once in awhile but to otherwise drive the car moderately. I've been doing a combination of wot bursts in 3rd and 4th gear at mid rpms (between 2.5 and 4k) and engine braking down hills to help seat the rings (trying to start the engine braking at 4k rpms or slightly below). I'm slowly working the rpms up as the miles climb but not going nuts or hitting the rev limiter haha

I usually do a couple bounces off limiter to let it know it's ok to get high. Beat it up, within reason.

Do you have more info about engine breaking as part of an engine break-in? I have not heard of this.

9T4YJ 12-19-2013 12:10 PM

Quote:

Originally Posted by RoadiJeff (Post 6839625)
I used to work in a Chrysler assembly plant. I was the first person to start the vehicle and drive it off the main line. I drove it straight to a roll test area where an inspector ran it through a series of tests for about 2 minutes at speeds up to 60 mph. It was nowhere near enough time to break-in a new engine, just enough time to verify that everything was operating normally.

I would imagine the setup at the Wrangler assembly plant is about the same.

It still goes pretty much the same way from what I understand. There are a number of "checks" along the line, then at the end they start it to make sure it runs, do a rolls check and drive it into the staging lot.

As for engine break-in, you can ask 100 different "experts" and get 1,000 different answers. The main thing is to vary RPM to prevent "grooving", and don't hammer on it for the first few hundred miles. I personally like to change my oil for the first time after about 1,000 miles or less on a new engine to make sure there isn't any excessive or a alarming pieces of debris. In addition, to make sure the oil filter on the engine is clear and flowing, a plugged oil filter can ruin your week really quick. When in doubt, folllow the manual. :happyyes:


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