Question about motor Break-in

[s14det]

I hopefully will be breaking in my motor this coming week and have a question. I have read the first 200 miles or so is when the rings break in and that you should not keep a constant RPM. Now does that mean after 200-300miles I can take it on the highway and drive it, or should i wait longer before keeping a constant RPM? I have read many break-in methods, but it never really states when you can start to keep a constant speed/RPM. I am going to use normal oil up to 1500 miles.

Thanks,

[Ezzo]

http://www.ntnoa.org/enginebreakin.htm

[Craving4Boost]

it says the initial run should be ran with little or no load and then shut down to cool. how long are we suppose to let it run before shutting it down?

[Chezedik]

I am sorry, but that is bull****! Are you going to grandma it the full life of the engine? Make sure it starts let it warm up, and beat the **** out of it. I do not mean to come off like a prick, but I get so angry when I still hear this misconception. Here is the reality. Wear has a lot more to do with piston feet traveled than it does with load. Also, in the beginning you WANT it to wear fast so the chrome moly rings will seat faster (unless you used cast, in that case shame on you). Finally, like anything else in this world, an engine is completely and totally consumable. If this was not true then they wouldn't keep making new ones (yes, I realize it is a flawed arguement, but I think you understand). Rape it 'til it blows and do it all over again.Sorry about that all, I will now get off of my soapbox. Again, I am not angry at you, just tired of the break-in myth.

[Florida240sx]

My break-in method.....Start engine and go for a cruise. ONce it's at operatign temp do a few pulls. Lettign the engine whine itself down. Get one it real hard and then le tit sit for about a minute an dthen shut-off. Wait 30minutes and repeat.Drivign around for about 30miles.With hard 2nd gear pulls all the way through 3rd. Park it and drain your oil. Don't drive over 50-75miles on fresh engine. Get that metal out of it. When engine is codl to touch go at it again. Change oil at another 75miles. Next change oil at 300miles. By this time engine should be broke in and all metal shavings should be gone.

[deviousKA]

Drive normally, if there is a problem with the engine, driving a certain way is not going to make it go away.

You do not want to load it up too heavily the first few hundred miles, drop down to a lower gear when climbing and keep the rpm's in the midrange as much as you can.

Cast rings break in very quickly and there is little precaution if the cylinder walls are well prepared. Moly rings take much longer to break in and should only be used on fresh bore.

We rebuild, sell and/or install japanese 4cyl engines at the shop on a daily basis, constant. All of our engines leave with full warranty and usually have less than 1hr/1mile run time,... just drive it.

[Craving4Boost]

I am sorry, but that is bull****! Are you going to grandma it the full life of the engine? Make sure it starts let it warm up, and beat the **** out of it. I do not mean to come off like a prick, but I get so angry when I still hear this misconception. Here is the reality. Wear has a lot more to do with piston feet traveled than it does with load. Also, in the beginning you WANT it to wear fast so the chrome moly rings will seat faster (unless you used cast, in that case shame on you). Finally, like anything else in this world, an engine is completely and totally consumable. If this was not true then they wouldn't keep making new ones (yes, I realize it is a flawed arguement, but I think you understand). Rape it 'til it blows and do it all over again.Sorry about that all, I will now get off of my soapbox. Again, I am not angry at you, just tired of the break-in myth.

are you reffering to me? if you are...you've misunderstood. when i said initial run...i did not mean the WHOLE break in procedure. if you read the link Ezzo had posted...which talked about HARD BREAK IN....it says initial run is little to no load. And now that i have re-read the link...the "initial run" is referring to the warming up of the engine. so to answer my question...i guess 5minutes.

[deviousKA]

My break-in method.....Start engine and go for a cruise. ONce it's at operatign temp do a few pulls. Lettign the engine whine itself down. Get one it real hard and then le tit sit for about a minute an dthen shut-off. Wait 30minutes and repeat.Drivign around for about 30miles.With hard 2nd gear pulls all the way through 3rd. Park it and drain your oil. Don't drive over 50-75miles on fresh engine. Get that metal out of it. When engine is codl to touch go at it again. Change oil at another 75miles. Next change oil at 300miles. By this time engine should be broke in and all metal shavings should be gone.

If you have metal shavings you have a problem, and that is a waste of oil. Also there is no need to do obnoxious WOT pulls to initially break in an engine, thats just asking for trouble.

[Craving4Boost]

Drive normally, if there is a problem with the engine, driving a certain way is not going to make it go away.

You do not want to load it up too heavily the first few hundred miles, drop down to a lower gear when climbing and keep the rpm's in the midrange as much as you can.

Cast rings break in very quickly and there is little precaution if the cylinder walls are well prepared. Moly rings take much longer to break in and should only be used on fresh bore.

We rebuild, sell and/or install japanese 4cyl engines at the shop on a daily basis, constant. All of our engines leave with full warranty and usually have less than 1hr/1mile run time,... just drive it.

its great to have your knowlegdeable input for this point. what about the full cooling down period? do you believe that it's necessary?

[Craving4Boost]

If you have metal shavings you have a problem, and that is a waste of oil. Also there is no need to do obnoxious WOT pulls to initially break in an engine, thats just asking for trouble.

not to mention speeding tickets in a small, crowded city like san francisco

[deviousKA]

No need for a cooling down period, treat the temps as you should with any engine. You should always allow a good amount of warm up time from a cold start, and dont allow it to overheat for whatever reason, pretty basic.

#1 cause of properly rebuilt engine failure is radiator/coolant issues. Get your radiator flushed, and any hoses/t.stat/w.pump replaced as necessary. Again, fairly basic stuff but you would be surprised what people do. Bascially only time we get engines back is when people dont replace their tattered coolant hoses, or if their radiator is full of stop leak (or similar junk) causing rapid overheating (void warranty of course).

Or, if they had an efi problem and thought the new engine they installed was going to magically fix everything Get those a lot.

[Craving4Boost]

how often would you change oil during break in?

[MarkEmark]

I've always thought that on break-in, there were more or less two principal schools of thought: the "break it in easy" ideology, and the "beat it from the beginning" ideology. Both work. Unless you do something really stupid during either period (e.g., allowing to overheat, or letting it idle for 30 minutes after initial start up(!!!) ), it should break in fine.

My first fully built engine (moly rings, of course) and wisecos broke in beautifully...until the stock connecting rods decided to fail After disassembling it due to that reason, however, the pistons and cylinder walls seem to have broken in nicely...

Did the same easy break-in with my new engine (wisecos and crowers this time). It has 1,000+ miles on it, no check-engine light, passed CT sniffers emissions, never stalls, etc...so this seems to be going well; When i get home I'm aiming for around 300whp @15 psi, which I know is a conservative guess...

To sum up: either school of thought works; it depends on which seems more sensible to you; the "break it in hard" school of thought seems counter-intuitive, for what it's worth.

PS...My break-in method: No boost for first 100 miles; 2 psi for next 200 miles, 4 psi for next 200 6 psi from 500-1000 miles. Mostly not full-throttle situations. VARY the engine load...do not just keep it at 3000 rpm in 5th on a highway...throughout the entire break in (1000 miles for me), make sure you're varying rpms and load (e.g., gears)....keep it all between 2500-5000 rpm.

[MarkEmark]

how often would you change oil during break in?

I changed it at 100 miles, 500 miles, 1000 miles...I'm just using Pennzoil 5w30 (dad's never had a problem with this oil and all the cars he's owned!).

[deviousKA]

You could change it after 3-400 miles, not the worst idea but not exactly necessary either, just keep it clean.

Watch the level, keep it halfway on the range on a KA (especially all the single cammers, do not overfill!)

[Craving4Boost]

You could change it after 3-400 miles, not the worst idea but not exactly necessary either, just keep it clean.

Watch the level, keep it halfway on the range on a KA (especially all the single cammers, do not overfill!)

why does everyone say the first 20mins oil change is very important?

[Chezedik]

I have to admit, Devious has a lot more experience in real life than I do, I work in theory. But of course, as Mark says, there are two schools. I do not intend to be easy on mine, I see no real point. But I guess the real answer is do what makes sense, if it is built correctly, it will work for you. How long depends on your tune after that.

[Craving4Boost]

does KA use moly rings or cast rings? whats moly?

[Chezedik]

Chrome-moly, it is what many of the stock Jap motors run. Cast iron is softer and tends to break in much faster. Also, it tends to be cheaper (although when I shopped for my rings, they were the same price).

[deviousKA]

Cast rings are widely used. Most of the rings you will get with forged piston sets are cast iron.

I use cast rings in all of my performance engines, with both cast and forged piston, instead of chrome moly. They break in much faster and are more consistent, plenty ample for any application. The only disadvantage is that they have roughly half the life of a moly ring, with both lifetimes well over 100k, generally speaking.

The break-in disadvantages of moly make the cast ring a much better choice for short life (<100k) performance engines.

Oh and btw, all of the ka24's use cast rings originally, except for a few select 98+ models such as the altima.

[Chezedik]

Really, my mistake. Now I feel like a tool. I have chrome, well, we will see how this works out, huh?

[deviousKA]

You joking?

It was just an opinion, nothing wrong with a moly ring unless your not running a fresh bore.

[Florida240sx]

Devious....I thought it took abotu 3 oil changes to cleanse your engine from metal shavings..... 1st one being the major....... Someone on here hs a pic of their oil which looks like a metallic paint job after 50-100miles....

[deviousKA]

Their next pictures will most likely be those of failure.

lol.

Seriously, there is not supposed to be any substantial amount of debris (chips) created during an engine break in. If there is a visible amount there is a problem.

So yes in that situation I would be changing the oil as well, but only as a feeble attempt to prolong or diagnose the problem, the oil should be clean.

[KATwo40]

FWIW: I ride dirbikes, and I ride them hard. Not only on the MX track, but through the harsh mountainous trails of East TN. We do river crossings deep enough to cover the seat of the bike.

When we re-ring our engines, we do it like this:

Tear down engine. Replace rings. Replace piston (only if needed). Replace crank/rod bearings (only if needed). Replace associated seals/gaskets.

Start bike, warm to operating temp, shut off. Take bike to MX track or trails. Ride like any other day...HARD.

To date: 0 failures.

[deviousKA]

Yeah but now if those are watercooled they have nickelsil coated cylinders, whole different ballgame as you have no option for overbore.

They last a long time though, and like you said you can re-ring various times and rap them out first time as much as you would like. The cylinder wall is essentially "fully glazed" already.

but not as a bust to start an arguement or anything

[Craving4Boost]

Devious are you really 20 years old like your profile says.

[wild_maxx]

i have been wondering that as well.... hes a smart dude huh...

[Craving4Boost]

i have been wondering that as well.... hes a smart dude huh...

gives me hope as a 18 year old lol....

[deviousKA]

Yep,

But ill be drinking age as of next month