Engine Break In
10-22-2009, 11:05 PM
#1
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Engine Break In
Just finished an engine rebuild. New pistons, rings, bearings, etc. What is the recommended break in. I have heard everything from start it, drain it to put 400 miles at less than 4000 rpm.
10-22-2009, 11:24 PM
#2
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Saw and heard your car start today Bob.. awesome.
I spit out the oil right away after a short 20-30 minute break in.. detergent free oil.. Then go drive her for about 50 miles.. Change oil to regular oil. Non synthetic for a while just to be sure. Then drive the **** out of her.
I spit out the oil right away after a short 20-30 minute break in.. detergent free oil.. Then go drive her for about 50 miles.. Change oil to regular oil. Non synthetic for a while just to be sure. Then drive the **** out of her.
10-22-2009, 11:55 PM
#3
Nordschleife Master
I don't know if our alusil cylinders make a difference, but in a "regular" engine you want to run dino oil for the first 1,000 miles. Changing at 100miles, 500 miles, then 1,000 miles. After that, use the oil of your choice.
At first start up, don't let the engine idle for any long periods. Make 15 to 20 runs at full throttle (but low or no boost) to 50mph (to create friction to break in rings) then coast down to 30mph (to create vacuum to suck up oil into the rings). Then drive normally, changing oil at prescribed intervals.
At first start up, don't let the engine idle for any long periods. Make 15 to 20 runs at full throttle (but low or no boost) to 50mph (to create friction to break in rings) then coast down to 30mph (to create vacuum to suck up oil into the rings). Then drive normally, changing oil at prescribed intervals.
10-23-2009, 12:03 AM
#5
Rennlist Member
I don't quite understand the merits of changing out the oil after a very short initial time on the oil. So, what happens when you leave the oil in for longer? You'd think the oil filter is going to trap unwanted particles; that's what it's there for.
Alot of engine manufacturers suggest an initial oil change interval of 2-3,000 miles with a good break-in oil.
Alot of engine manufacturers suggest an initial oil change interval of 2-3,000 miles with a good break-in oil.
10-23-2009, 04:53 AM
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10-23-2009, 08:59 AM
#8
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Non detergent oil for initial break in (Rotella form NAPA is a good choice). Too many additives (as well as synthetics) interfere with the break in process.
Change oil and filter after first heat cycle (flush out any contaminates from the machining process) – for those wondering about this – the oil filter will run in ‘bypass’ mode when the oil is thick and cold. So think about that – no filtering when the oil is thick and at high pressure.
Important – after the first run do a hose clamp check – some will need to be tightened after being heat cycled.
When it comes to how to drive the car you will get a lot of different advice. The old advice that seems to still apply – break it in as you would drive it later.
There are a couple of things to pay attention to –
If it’s a new cam do not let it idle. Run at 3k rpm after initial start up.
Do not run overly rich – it will wash the oil off the cylinder walls (this is the only reason not to run boost initially)
Lift off the gas at regular intervals to draw oil in to the cylinders (high vacuum)
Drive at varying RPMs, do not cruise at the same RPM for prolonged periods.
Pay attention and stop smiling too much…!
Change oil and filter after first heat cycle (flush out any contaminates from the machining process) – for those wondering about this – the oil filter will run in ‘bypass’ mode when the oil is thick and cold. So think about that – no filtering when the oil is thick and at high pressure.
Important – after the first run do a hose clamp check – some will need to be tightened after being heat cycled.
When it comes to how to drive the car you will get a lot of different advice. The old advice that seems to still apply – break it in as you would drive it later.
There are a couple of things to pay attention to –
If it’s a new cam do not let it idle. Run at 3k rpm after initial start up.
Do not run overly rich – it will wash the oil off the cylinder walls (this is the only reason not to run boost initially)
Lift off the gas at regular intervals to draw oil in to the cylinders (high vacuum)
Drive at varying RPMs, do not cruise at the same RPM for prolonged periods.
Pay attention and stop smiling too much…!
10-23-2009, 01:48 PM
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I will add my 2 cents...
keep rpm < ~75% of redline for 1000 mi
always get it warmed up before applying load
gradual load application, no lugging
vary rpm's/load, no long steady cruises
try some mountain drives up/down hills to seat the rings...
change oil
might be worth an oil analysis
up to 3000 miles, basically the same except 100% of redline...
change oil, let her rip
keep rpm < ~75% of redline for 1000 mi
always get it warmed up before applying load
gradual load application, no lugging
vary rpm's/load, no long steady cruises
try some mountain drives up/down hills to seat the rings...
change oil
might be worth an oil analysis
up to 3000 miles, basically the same except 100% of redline...
change oil, let her rip
10-23-2009, 02:26 PM
#10
I can't imagine this would be any different in a car... but just note this is how I've always broken in motorcycles:
Street machine - ~100 miles on it, easy running. Varied RPMs, put some load on it but no WOT redline passes. Stop at 100 miles, change oil and filter. From there - beat the hell out of it. For good measure I've changed the oil again at 500 and 1000 miles, but it probably didn't matter much. I've done this with 5-6 new bikes and each one was "fast" for what it was (as in, ran it against an identical bike and mine was always considerably faster.) Can't comment on the longevity though. But for power, this worked best.
Race machine - first start up, was just idle it to operating temp (where t-stat opens), then shut it down and let it cool all the way down to where it's cold. 2nd start was on a dyno, warm up to operating temp, a few WOT passes but not to redline, letting it idle back down from ~8,000rpm or so (on a 16k rpm redline.) Let it sit until cold. 3rd start, warm up, 2-3 WOT redline passes, shut down till cold. From there, run a 15 minute track session at ~90% as a shakedown just to make sure nothing shakes loose. Then she's good to go. I never had issues with my race motors.
None of these were for motors where I expected them to last 100k (or even 50k) so keep that in mind.
Street machine - ~100 miles on it, easy running. Varied RPMs, put some load on it but no WOT redline passes. Stop at 100 miles, change oil and filter. From there - beat the hell out of it. For good measure I've changed the oil again at 500 and 1000 miles, but it probably didn't matter much. I've done this with 5-6 new bikes and each one was "fast" for what it was (as in, ran it against an identical bike and mine was always considerably faster.) Can't comment on the longevity though. But for power, this worked best.
Race machine - first start up, was just idle it to operating temp (where t-stat opens), then shut it down and let it cool all the way down to where it's cold. 2nd start was on a dyno, warm up to operating temp, a few WOT passes but not to redline, letting it idle back down from ~8,000rpm or so (on a 16k rpm redline.) Let it sit until cold. 3rd start, warm up, 2-3 WOT redline passes, shut down till cold. From there, run a 15 minute track session at ~90% as a shakedown just to make sure nothing shakes loose. Then she's good to go. I never had issues with my race motors.
None of these were for motors where I expected them to last 100k (or even 50k) so keep that in mind.
