Engine break-in questions

[franksta]

The goal of the break-in procedure I used/am familiar with there were a couple of specific goals I was trying to achieve. One was to get the rings to seal in the cylinders. The other was to work-harden the lifters. The cylinders are made with a rough surface and as the rings slide against this rough surface they wear down and the seal gets better. Better seal = better compression = more power. The lifters had to be hardened against the camshaft but I forget the reasoning. I think it's such that they don't wear as much later in life and make the cam feel like it has "gone flat". Don't quote me on that I don't remember well.

You can seat the rings in by varying the motor speed against a load. Just sitting in your drive-way reving the thing doesn't count. Drive your new motor around town. Also maintain the load on the motor. So no lugging the poor thing, not that you should ever do that but it's particularly important for break-in. The procedure I have for the lifters is more specific to the motor (aircooled VW) but it essentially is started up and immediately brought up to about 3000 RPM and should be varied around the mid-range for 15 minutes or so. Turn it off, chainge the oil, wait for the motor to cool completely, check and adjust the valve lash, then drive it around town.

 

[SilthDraeth]

Originally posted by: evident

honda and honda enthusiasts say not to change the oil till 3000-4000 miles initially on their cars, because Honda includes some special type of oil initially.... i think i'm going to trust them on that

To each their own.

The 3k oil change is your standard oil change interval quoted for most automobiles, though some are stating 5k oil changes now, in which case your 4k falls right in between.

I sincerely doubt that Honda has access to a "special" oil just to ship in their brand new cars. Unless the oil is intended to allow a higher level of wear vs normal oil, and that simply wouldn't make any sense.

 

[jagec]

Originally posted by: evident

Originally posted by: SilthDraeth
You are supposed to vary your speed. You need to go through all the gears several times.

Also do your first oil change at 1k miles. Throw in a good synthetic, then change it again at 3k miles. The first oil in there gets really really dirty. My 2006 Tacoma, I put in Amsoil at 1k miles, and the oil was nasty thick and black from all initial burn off.

honda and honda enthusiasts say not to change the oil till 3000-4000 miles initially on their cars, because Honda includes some special type of oil initially.... i think i'm going to trust them on that

I doubt Honda says "not" to change the oil until 3k. They probably just say TO change the oil at 3k. The first implies that you'll damage the engine if you change earlier, the second just implies that it won't make a significant difference to change earlier.

 

[Jeff7181]

Someone suggested CVT's are counterproductive to varying engine speed to properly break in an engine. I'm not sure where the logic is behind that reasoning. A CVT doesn't maintain constant RPM. It keeps the engine at the most efficient RPM for the conditions. If you're cruising at 70 mph, the engine RPM is going to remain constant whether you have a traditional automatic, a manual, or a CVT. Engine RPM varies almost just as much with a CVT as any other because it adjusts gear ratios to put the engine at the RPM that provides the best performance/economy for the current conditions.

From a dead stop, if I accelerate at a quick but not obnoxious rate, the engine RPM comes up to about 2800, when I hit 25 mph it's at about 3000 RPM, and when I hit 45 mph it's at about 3200 RPM. It adjusts the RPM to maintain a constant rate of acceleration. When I let off, it adjusts the gear ratio to reduce the RPM to a more economical speed for cruising.

 

[jagec]

Originally posted by: Jeff7181
Someone suggested CVT's are counterproductive to varying engine speed to properly break in an engine. I'm not sure where the logic is behind that reasoning. A CVT doesn't maintain constant RPM. It keeps the engine at the most efficient RPM for the conditions. If you're cruising at 70 mph, the engine RPM is going to remain constant whether you have a traditional automatic, a manual, or a CVT. Engine RPM varies almost just as much with a CVT as any other because it adjusts gear ratios to put the engine at the RPM that provides the best performance/economy for the current conditions.

From a dead stop, if I accelerate at a quick but not obnoxious rate, the engine RPM comes up to about 2800, when I hit 25 mph it's at about 3000 RPM, and when I hit 45 mph it's at about 3200 RPM. It adjusts the RPM to maintain a constant rate of acceleration. When I let off, it adjusts the gear ratio to reduce the RPM to a more economical speed for cruising.

I dream of a manual CVT...Shove it to the maximum ratio at the light, take off and smoothly slide it upwards to keep the engine in its powerband as you accelerate, and then adjust it to the lowest RPM you need to cruise.

Of course, the manufacturers would never go for it.

 

[Jeff7181]

Originally posted by: jagec

Originally posted by: Jeff7181
Someone suggested CVT's are counterproductive to varying engine speed to properly break in an engine. I'm not sure where the logic is behind that reasoning. A CVT doesn't maintain constant RPM. It keeps the engine at the most efficient RPM for the conditions. If you're cruising at 70 mph, the engine RPM is going to remain constant whether you have a traditional automatic, a manual, or a CVT. Engine RPM varies almost just as much with a CVT as any other because it adjusts gear ratios to put the engine at the RPM that provides the best performance/economy for the current conditions.

From a dead stop, if I accelerate at a quick but not obnoxious rate, the engine RPM comes up to about 2800, when I hit 25 mph it's at about 3000 RPM, and when I hit 45 mph it's at about 3200 RPM. It adjusts the RPM to maintain a constant rate of acceleration. When I let off, it adjusts the gear ratio to reduce the RPM to a more economical speed for cruising.

I dream of a manual CVT...Shove it to the maximum ratio at the light, take off and smoothly slide it upwards to keep the engine in its powerband as you accelerate, and then adjust it to the lowest RPM you need to cruise.

Of course, the manufacturers would never go for it.

A manual CVT? So... you want to be able to adjust the near infinite gear ratios yourself while driving?

 

[jagec]

Originally posted by: Jeff7181


A manual CVT? So... you want to be able to adjust the near infinite gear ratios yourself while driving?

Yes, that is what I just described. Like a slider from the lowest to the highest ratio. It certainly would take some time to get used to, but I think I'd enjoy it.

 

[Pacfanweb]

Originally posted by: SilthDraeth

Originally posted by: evident

honda and honda enthusiasts say not to change the oil till 3000-4000 miles initially on their cars, because Honda includes some special type of oil initially.... i think i'm going to trust them on that

To each their own.

The 3k oil change is your standard oil change interval quoted for most automobiles, though some are stating 5k oil changes now, in which case your 4k falls right in between.

Actually, most auto maker specify 5-7500 mile oil change intervals, and have been for years.
3k is only recommended now for "severe duty" use. Taxi cabs, police cars, etc....cars that are basically never turned off.

 

[Jeff7181]

Originally posted by: jagec

Originally posted by: Jeff7181


A manual CVT? So... you want to be able to adjust the near infinite gear ratios yourself while driving?

Yes, that is what I just described. Like a slider from the lowest to the highest ratio. It certainly would take some time to get used to, but I think I'd enjoy it.

Ahh... I gotcha. That would be a tricky balancing act when accelerating at part throttle.

 

[SilthDraeth]

Originally posted by: Pacfanweb

Actually, most auto maker specify 5-7500 mile oil change intervals, and have been for years.
3k is only recommended now for "severe duty" use. Taxi cabs, police cars, etc....cars that are basically never turned off.

True. But if you read what "severe service" is, most owner's manuals state, if you primarily drive in stop and go traffic (ie city driving vs highway) a lot more people fall in the severe service category than they think.

 

[Pacfanweb]

Originally posted by: SilthDraeth

Originally posted by: Pacfanweb

Actually, most auto maker specify 5-7500 mile oil change intervals, and have been for years.
3k is only recommended now for "severe duty" use. Taxi cabs, police cars, etc....cars that are basically never turned off.

True. But if you read what "severe service" is, most owner's manuals state, if you primarily drive in stop and go traffic (ie city driving vs highway) a lot more people fall in the severe service category than they think.

Nope. Most people who think they might need the severe duty maintenance really don't meet the conditions.

Here is what Ford considers severe duty for a 2006 Focus (and most anything else they make)

* Towing a trailer or using a camper or car-top carrier
* Extensive idling and/or low-speed driving for long distances as in heavy commercial use such as delivery, taxi, patrol car or livery
* Operating in dusty conditions such as unpaved or dusty roads
* Off-road operation
* Use of E85 50% of the time or greater (flex fuel vehicles only)

 

[SilthDraeth]

Originally posted by: Pacfanweb

Originally posted by: SilthDraeth

Originally posted by: Pacfanweb

Actually, most auto maker specify 5-7500 mile oil change intervals, and have been for years.
3k is only recommended now for "severe duty" use. Taxi cabs, police cars, etc....cars that are basically never turned off.

True. But if you read what "severe service" is, most owner's manuals state, if you primarily drive in stop and go traffic (ie city driving vs highway) a lot more people fall in the severe service category than they think.

Nope. Most people who think they might need the severe duty maintenance really don't meet the conditions.

Here is what Ford considers severe duty for a 2006 Focus (and most anything else they make)

* Towing a trailer or using a camper or car-top carrier
* Extensive idling and/or low-speed driving for long distances as in heavy commercial use such as delivery, taxi, patrol car or livery
* Operating in dusty conditions such as unpaved or dusty roads
* Off-road operation
* Use of E85 50% of the time or greater (flex fuel vehicles only)

Ok.