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Topic Review (Newest First)
10-07-2014 02:38 PM
derf
Quote:
Originally Posted by loudvegas View Post
What do you think happens to the hundreds of thousands of rental cars over the years? They get dropped off a lot BRAND NEW and do you think the average peson thinks twice about letting it run to redline?
https://www.youtube.com/watch?v=mAc5wjSi-Jk
10-07-2014 01:09 PM
Treeturdy
Quote:
Originally Posted by loudvegas View Post
What do you think happens to the hundreds of thousands of rental cars over the years? They get dropped off a lot BRAND NEW and do you think the average peson thinks twice about letting it run to redline? What about all of the dealer test drives where they tell you to get on it and see if you like the power. The truth of the matter is, it does not matter as long as it's warmed up. Just don't circle track race it with the engine running at the top 90% of the rev rage...or mor realisitically for us, give it hell trying to get unstuck while it's new and you are fine. Just drive it.
Although I agree on everything, one observation I can make is that rental car companies don't keep their cars for much more then a year or two if that.
10-07-2014 12:45 PM
loudvegas What do you think happens to the hundreds of thousands of rental cars over the years? They get dropped off a lot BRAND NEW and do you think the average peson thinks twice about letting it run to redline?

What about all of the dealer test drives where they tell you to get on it and see if you like the power.

The truth of the matter is, it does not matter as long as it's warmed up. Just don't circle track race it with the engine running at the top 90% of the rev rage...or mor realisitically for us, give it hell trying to get unstuck while it's new and you are fine.

Just drive it.
10-07-2014 07:04 AM
Treeturdy
Quote:
Originally Posted by spinlock View Post
I wouldn't sweat it. It's unlike one brief spool up of the engine will cause long lasting damage but if it did you will have some issues in the very short term (long before your warranty expires) or in the very long term (past 5-7 years). Unless the 300 miles were all on the highway, it is a reasonable break in period since the whole drive line was able to heat cycle repeatedly.
I hope you're wrong about the long term part tho,
10-06-2014 09:57 PM
demarpaint
Quote:
Originally Posted by Treeturdy View Post
I feel dumb after reading this, on Friday, I took my new Wrangler out, When I went to merge Onto the highway. I gave it way too much throttle, and it shot the engine speed super high, into the 5000-5500 range, It runs okay, but I'm worried that the long term service life may be affected by one stupid WOT burst in my first few weeks of owning it. The car had about 300 miles on it when this happened.. Is that too early? Am I going to be burning oil in 35k miles because The valves didn't seat?
I remember the lot boys parking new vehicles or moving them around. Cold engine 5 grand hole shots were not uncommon. First gear runs to red line weren't uncommon either. They didn't break, and probably lived a long life after that.
10-06-2014 09:53 PM
Treeturdy Woot!
I must say tho, that pentastar engine really makes a diffrence, Could have never done that in the old 2.5 yj!
10-06-2014 08:55 PM
RoadiJeff
Quote:
Originally Posted by Treeturdy View Post
The car had about 300 miles on it when this happened.. Is that too early? Am I going to be burning oil in 35k miles because The valves didn't seat?
I think the main thing you should be concerned about is that you killed a cute little kitten by calling your Jeep a car.

Anyway, I used to work at a Chrysler manufacturing plant. You should see what some of the brand new vehicles were put through on the roll test machine that just came off the assembly line and the engines had been started for the first time less than 5 minutes prior to that.

If the tests they went through led to some type of early engine failure I suspect the inspectors would not be told to do those tests. I think you'll be OK, just don't make a habit of it. And be kind to kittens.
10-06-2014 06:53 PM
spinlock I wouldn't sweat it. It's unlike one brief spool up of the engine will cause long lasting damage but if it did you will have some issues in the very short term (long before your warranty expires) or in the very long term (past 5-7 years). Unless the 300 miles were all on the highway, it is a reasonable break in period since the whole drive line was able to heat cycle repeatedly.
10-06-2014 06:35 PM
Treeturdy Anyone?
10-06-2014 05:34 PM
Treeturdy I feel dumb after reading this, on Friday, I took my new Wrangler out, When I went to merge Onto the highway. I gave it way too much throttle, and it shot the engine speed super high, into the 5000-5500 range, It runs okay, but I'm worried that the long term service life may be affected by one stupid WOT burst in my first few weeks of owning it. The car had about 300 miles on it when this happened.. Is that too early? Am I going to be burning oil in 35k miles because The valves didn't seat?
12-19-2013 01:10 PM
9T4YJ
Quote:
Originally Posted by RoadiJeff View Post
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.
12-19-2013 11:37 AM
COStrider
Quote:
Originally Posted by TexasBob View Post
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.
12-19-2013 11:32 AM
demarpaint
Quote:
Originally Posted by TexasBob View Post
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.
12-19-2013 10:34 AM
derf Just make sure the engine is up to operating temperature before you get on it. Also, just do short bursts.
12-19-2013 10:16 AM
TexasBob 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
12-18-2013 06:46 PM
Xena1 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.
12-18-2013 11:28 AM
Old Dogger 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.......
12-18-2013 11:09 AM
derf
Quote:
Originally Posted by RoadiJeff View Post
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.
12-18-2013 09:35 AM
michaeldc46
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)
12-18-2013 01:56 AM
COStrider
Quote:
Originally Posted by RoadiJeff View Post
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!
12-18-2013 01:09 AM
RoadiJeff 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.
12-17-2013 04:47 PM
derf
Quote:
Originally Posted by COStrider View Post
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.
12-17-2013 04:36 PM
COStrider
Quote:
Originally Posted by derf View Post
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!
12-17-2013 04:34 PM
derf
Quote:
Originally Posted by Blastek View Post
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.
12-17-2013 02:06 PM
Old Dogger Just break it in the way your manual recommends, and you will be good to go........
12-17-2013 01:57 PM
COStrider http://www.examiner.com/article/how-...k-a-new-engine
12-17-2013 12:35 PM
COStrider
Quote:
Originally Posted by Blastek View Post
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.
12-17-2013 12:06 PM
Blastek
Quote:
Originally Posted by derf View Post
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.
12-17-2013 12:00 PM
derf
Quote:
Originally Posted by Blastek View Post
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.
12-17-2013 11:57 AM
Blastek 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.
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