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allTRACway
08-19-2013, 10:32 AM
I know this is a very controversial and touchy subject but with this being my first engine rebuild I am looking for as much input as I can get. So the story goes my 02 corolla blew up and it had to rebuild it, it has all new internals and a rebuilt head. The information I am seeking is what is the best oil to use for the brake in period if i will be using synthetic oil and how should my fir 500 or so miles of driving be?

I have been told to use diesel oil, John Deere break in oil, conventional oil for the first 500 miles, and to just go straight to synthetic.

For initial driving style I have been told to start the car let it run at 2500 rpm for 30 minutes change the oil then go beat the crap out of it, told not to go over 55 and fluctuate my speed, and told to just make sure the oil pressures good and go run it like I drive every day.

I drive my cars hard so i'm looking for the best break in possible.

Any help is appreciated

Nitro_Alltrac
08-19-2013, 11:47 AM
From everything I've read, use conventional oil for the break in period. After that, you can go synthetic. That is what I would do myself.

As for the break in period, I've heard about the same thing you have. This question came up several times at AT.net several years ago and the consensus there was to go ahead and run the engine hard. I don't know if I'd do the run 30 minutes and change the oil thing. If the engine went back together clean, there really shouldn't be a lot of need to do that. I know for sure that Toyota doesn't do that at the factory. I think the main thing in the break in period is to make sure that you vary your engine speed during break in.

Doowstados
08-19-2013, 12:59 PM
When I bought my remanufactured engine from Promar in NJ (a very well respected performance engine remanufacturer) they recommended I do the 30 mins at 2,500 then change the oil (conventional only) as well. Same with the not going over 55 mph for the first 500 miles and fluctuating speed. They also said that for the first 50 miles try to accelerate to 35-45 mph as quickly as possible without going over 3,500 rpms then brake to 20-30 mph and repeat if you're in an area where you can do that.

Oh, and they also said to wait until 10,000 miles to switch to synthetic because you'll want to do the first few oil changes at closer intervals.

The Captain
08-19-2013, 03:26 PM
When I bought my remanufactured engine from Promar in NJ (a very well respected performance engine remanufacturer) they recommended I do the 30 mins at 2,500 then change the oil (conventional only) as well. Same with the not going over 55 mph for the first 500 miles and fluctuating speed. They also said that for the first 50 miles try to accelerate to 35-45 mph as quickly as possible without going over 3,500 rpms then brake to 20-30 mph and repeat if you're in an area where you can do that.

Oh, and they also said to wait until 10,000 miles to switch to synthetic because you'll want to do the first few oil changes at closer intervals.
This. Although 15 minutes for the first run is plenty. Let fully cool after that. Other than that, everything above is spot on. Your owners manual talks about the break in procedure.

donteatbugs
08-19-2013, 08:13 PM
I usually do hard engine braking down a steep hill in 2nd or third gear letting the car build the pressure in the cylinders. I also boosted about 14 lbs while I was breaking it in. My motor is still together and runs fine.

MrWOT
08-19-2013, 08:26 PM
Cam breakin and cylinder breakin are opposing processes unfortunately. Steady state is for cam breakin. For cylinders you want full throttle to redline, then snap the throttle shut and let it coast down under high vac.

Luni
08-19-2013, 09:11 PM
^This.

Although heat cycling is also very important. So after every run, its important to let the engine cool down completely.

allTRACway
08-21-2013, 02:24 PM
I'm also going to be running a meth injection kit, when is a good time to install that?

Facime
08-21-2013, 07:06 PM
I don't know if I'd do the run 30 minutes and change the oil thing. If the engine went back together clean, there really shouldn't be a lot of need to do that.

This initial run in period is where most of the ring break in occurs. If you have your oil analyed from this period you will find alot of iron in it from the clyinder walls and the rings. This is also why I recommend NOT just letting the motor run static speed under no load for this period. You should take the car out and using 3rd or 4th gear do som high load pulls letting the engine compression break you back down to near idle. In other words, get to an open area ASAP, get the car to 4th and do 3/4 throttle pulls to around 5K rpm, snap shut and engine brake to 2K, REPEAT for about 15 minutes, then park and let engine cool completely.

After that you can either drive it like you stole it or do an easy break in period for the rotating assemblies.


The problem with this topic and why you have so many differing opinions is that alot of older mechanics stick to a rigid old way of thinking that usually doesnt take into account how much technology, metallurgy and machining tolerances have changed in the last 20 years. The thing is...if you built the motor right, paying strict attention to tolerances, used quality parts, proper torque specs and sequences with a good assembly lube...it shouldnt really mattter a whole lot how you break it in.

The only thing I can tell you that everyone with a brain will agree on is that you need to use conventional oil during the break in period. Whether is diesel oil, standard automotive oil or even motorcycle oil (no friction modifyers) is up to you. Some friction is required during break in and synthetic is just too slick to do the job effectively. As for converting over from dino to synth at some point. Most synth is really a blend anyway and there is no real issue with following one with the other or even converting back again.

Luni
08-22-2013, 02:14 AM
I dont let it run for 30 minutes, but I do let it run long enough to bleed the coolant and make sure nothing is leaking, and get up to temp. It certainly isnt hurting anything to do it that way. As Hippie said there are a bunch of varying opinions on this.

MrWOT
08-22-2013, 02:23 AM
The synth thing is a myth. I think it's a waste, because I'm a cheap bastard and tossing out expensive oil makes my teeth itch, but it won't affect breakin. This I have straight from the horses mouth from two different pro builders who make engines that cost more than I make in a year.

The machining process also matters, if you have a plateau hone is performed, cylinder breakin is pretty much 95% complete from the get-go and you can fill it with synthetic and drive it to regular service intervals immediately.

If it's a regular stone hone, break it in like I posted before. You can help minimize the amount of breakin required by asking them to take out 2x as much material with the hone, and lessen the cut with the boring bar. If they want to charge an extra couple bucks, do it anyway.

MCcelica
08-26-2013, 11:56 PM
The synth thing is a myth. I think it's a waste, because I'm a cheap bastard and tossing out expensive oil makes my teeth itch, but it won't affect breakin. This I have straight from the horses mouth from two different pro builders who make engines that cost more than I make in a year.

The machining process also matters, if you have a plateau hone is performed, cylinder breakin is pretty much 95% complete from the get-go and you can fill it with synthetic and drive it to regular service intervals immediately.

If it's a regular stone hone, break it in like I posted before. You can help minimize the amount of breakin required by asking them to take out 2x as much material with the hone, and lessen the cut with the boring bar. If they want to charge an extra couple bucks, do it anyway.

That is why I advise what I'm about to say. There is a lot of anecdotal evidence everywhere, which is why opinions differ so much. You can say "if this" and "if that" but the only "if" that matters is this. If you took the engine to a shop to be rebuilt and they have a warranty for their work, make sure you follow what that shop has to say for the break in period. That way if you do what they say and it still breaks, you're covered under the warranty.

If you did the rebuild yourself, feel free to break it in any way you wish using the advice in the thread. But make sure to pay attention to the details like what kind of honing was done, etc.

allTRACway
08-28-2013, 05:34 PM
I did the rebuild my self and its been bored 20 over.