Constant speeds and the break in period
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Things happen in break-in.
On the throttle, cruise, off the throttle creates pressure, then vacuum to pull oil past the rings and help lube upper cylinder walls.
High RPM's stretch the rods on the exhaust stroke, so varying the upper RPM's stops any incipient ridge formation. Most engine benefit from a run to red line now and then. It does not have to be at full throttle. It can be down shifting descending a hill. Just need to work the whole ring band in the cylinder
On the throttle, cruise, off the throttle creates pressure, then vacuum to pull oil past the rings and help lube upper cylinder walls.
High RPM's stretch the rods on the exhaust stroke, so varying the upper RPM's stops any incipient ridge formation. Most engine benefit from a run to red line now and then. It does not have to be at full throttle. It can be down shifting descending a hill. Just need to work the whole ring band in the cylinder
Originally Posted By: SilverFusion2010
I advocate the mototune USA method. You have to load the engine to seal the rings
Anti hard break-in rant.
I advocate the mototune USA method. You have to load the engine to seal the rings
Anti hard break-in rant.
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Originally Posted By: eljefino
Originally Posted By: philipp10
For the life of me I cannot understand the break in routines. Other than not stomping on it (resulting in high cylinder pressures), how and why would variable rpm matter. The piston still goes up and down in the bore.
Supposedly high revs stretch the con-rods a little bit and the rings ram into a ridge at the top of the liners. But I could see this only being a problem if you run it slow for a long time (years) then give 'er the beans.
I wouldn't drive it up Mt Washington but a little blip up into the fun zone, all warmed up, seems useful and harmless.
That's what happens when grandmas old car gets passed down to her 16 year old nephew
Originally Posted By: philipp10
For the life of me I cannot understand the break in routines. Other than not stomping on it (resulting in high cylinder pressures), how and why would variable rpm matter. The piston still goes up and down in the bore.
Supposedly high revs stretch the con-rods a little bit and the rings ram into a ridge at the top of the liners. But I could see this only being a problem if you run it slow for a long time (years) then give 'er the beans.
I wouldn't drive it up Mt Washington but a little blip up into the fun zone, all warmed up, seems useful and harmless.
That's what happens when grandmas old car gets passed down to her 16 year old nephew
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Originally Posted By: merconvvv
Can you break in a car after you baby it for 10 years.
Would the car know ?
Machined parts are very rough compared to what it becomes after running for a certain time and rubbing together. That's what's breaking in. Mating two parts together.
Can you break in a car after you baby it for 10 years.
Would the car know ?
Machined parts are very rough compared to what it becomes after running for a certain time and rubbing together. That's what's breaking in. Mating two parts together.
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Originally Posted By: eljefino
... Supposedly high revs stretch the con-rods a little bit and the rings ram into a ridge at the top of the liners. But I could see this only being a problem if you run it slow for a long time (years) then give 'er the beans. ...
Somehow I doubt that's often a big risk, considering my Mazda had no discernable ridges at the tops at 476K miles when I looked.
... Supposedly high revs stretch the con-rods a little bit and the rings ram into a ridge at the top of the liners. But I could see this only being a problem if you run it slow for a long time (years) then give 'er the beans. ...
Somehow I doubt that's often a big risk, considering my Mazda had no discernable ridges at the tops at 476K miles when I looked.
In engineering college 40+ years ago there was mention of coaxing a new engine to a higher level of ultimate performance through high loads while new. I've never heard the idea discussed since then.
Is there any validity to the concept? Or just another bad idea?
One of my physics professors had a theory that cars rust because their paint is damaged by washing. So he didn't wash his own brand new Volvo for several years - with predictable results! Not every idea is a good idea.
Is there any validity to the concept? Or just another bad idea?
One of my physics professors had a theory that cars rust because their paint is damaged by washing. So he didn't wash his own brand new Volvo for several years - with predictable results! Not every idea is a good idea.
With that 0W-20 Toyota uses now, I don't see how you could not break an engine in.
Chrysler now recommends giving it the beans during break in. At least they do on the 3.6 V6 right in the owners manual. I've always followed the motune USA and had no problems or oil use.
My approach with new vehicles:
Never warm up engine. Start, a few seconds for oil flow then drive gently. Faster warm-up, less fuel dilution of oil and pollutants. This is good even after break in.
Once oil is warm (which is somewhat after coolant) then full throttle. Never from a standing start, never to redline and never in first gear. Don't lug the motor in too tall of a gear either. Let off about half to 3/4 of redline.
Obviously keep an eye for traffic and police
Let engine cruise and cool then repeat. Do this about four times every drive. At 500 miles she's as broken in as she's gonna get.
Drop oil and filter before 1k miles. Do it again at 3-5k. Don't use cruise before first oil change.
Around 3k I get a smoother engine. Never used a drop of oil. My missus drives hers like a baby. I swear that thing burns more oil than a two stroke!
My approach with new vehicles:
Never warm up engine. Start, a few seconds for oil flow then drive gently. Faster warm-up, less fuel dilution of oil and pollutants. This is good even after break in.
Once oil is warm (which is somewhat after coolant) then full throttle. Never from a standing start, never to redline and never in first gear. Don't lug the motor in too tall of a gear either. Let off about half to 3/4 of redline.
Obviously keep an eye for traffic and police
Let engine cruise and cool then repeat. Do this about four times every drive. At 500 miles she's as broken in as she's gonna get.
Drop oil and filter before 1k miles. Do it again at 3-5k. Don't use cruise before first oil change.
Around 3k I get a smoother engine. Never used a drop of oil. My missus drives hers like a baby. I swear that thing burns more oil than a two stroke!
Originally Posted By: DdDd
Chrysler now recommends giving it the beans during break in. At least they do on the 3.6 V6 right in the owners manual. I've always followed the motune USA and had no problems or oil use.
My 06 Chrysler 6.1 states specifically that "full throttle is beneficial to engine break in".
This engine is a notable oil user, yet my oil has never moved on the stick even at all day track events.
Break in is also for the driveline, so upper gears are better, more load, too...
Chrysler now recommends giving it the beans during break in. At least they do on the 3.6 V6 right in the owners manual. I've always followed the motune USA and had no problems or oil use.
My 06 Chrysler 6.1 states specifically that "full throttle is beneficial to engine break in".
This engine is a notable oil user, yet my oil has never moved on the stick even at all day track events.
Break in is also for the driveline, so upper gears are better, more load, too...
Originally Posted By: AVB
lol. I have witnessed a brand new Cadillac CTS-V do 148 with 4 techs riding in it. I have seen brand new vehicles drag race other brand new vehicles during the PDI. You don't know how it was treated prior to you. It is kind of a double edged sword, if something is going to break you want it to happen while it is under warranty.
This. Every car I ever PDI'd got a run to the redline during the road test. People worry too much...
lol. I have witnessed a brand new Cadillac CTS-V do 148 with 4 techs riding in it. I have seen brand new vehicles drag race other brand new vehicles during the PDI. You don't know how it was treated prior to you. It is kind of a double edged sword, if something is going to break you want it to happen while it is under warranty.
This. Every car I ever PDI'd got a run to the redline during the road test. People worry too much...
Originally Posted By: merconvvv
Can you break in a car after you baby it for 10 years.
Would the car know ?
You sure can. Bring the revs up over time slowly higher and higher not just beat on it but done carefully can prevent broken compression rings on a engine that has really been driven by old lady around town at 30 mph for years.
You cannot however seat rings that were not seated properly in the first hours of the new engines life, that's a one shot deal.
Can you break in a car after you baby it for 10 years.
Would the car know ?
You sure can. Bring the revs up over time slowly higher and higher not just beat on it but done carefully can prevent broken compression rings on a engine that has really been driven by old lady around town at 30 mph for years.
You cannot however seat rings that were not seated properly in the first hours of the new engines life, that's a one shot deal.
Connecting rods would stretch more from temperature thermal expansion than the force a piston could put on them. these things are pretty heavy duty and enough force to stretch them would mean piston sticking too much which is not likely when new. Con rods break sometimes when no oil is present and the engine seizes. Common failure for neglectful people not checking or changing oil
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