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1G Engine Break In Methods?

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dsmalaska

Proven Member
75
1
Dec 18, 2013
Avondale, Arizona
just about to put my motor together but im looking in to break in methods now. I read motosmans method but I just want a clearer understanding. So basically im to let it idle to op temp for 20 minutes, change oil, go drive for 20 miles with pulls in 2,3,4 gear allowing it to pull full vacuum after each pull, do that about 3-5 times to 50 mph correct?. then what after that? I know to use conventional oil, ill look to see if I can find any specific engine break in oil. but any suggestions would help, want to make sure the rings seat and everything is good to go. Btw its just a plain jane rebuild, not for power just for a reliable dd till I get out of tech school and can afford another dd and project car. thanks guys
 
that is a good method. but the first part.. let idle and run to op temp, then allow to FULLY cool off then let idle to op temp before going to drive. there is red line and royal purple break in oil, but those aren't necessary.
 
I was told by a well known machinist to use the motoman way on my brake in, however, I was too paranoid to use the brake in with nothing but hard driving. motoman brake in goes against everything in my nature for braking in a car. Personally I just let it get up to themp and check for leaks. If everything is idling good and not over heating start driving alittle bit and just dont sit at one RPM for too long. Go up and down a lot with the RPMs, no cruising! I wouldnt red line it either. But this is just my .02, I am not a ASE tech, just someone that just rebuilt my motor and is at 500miles with no problems. good luck!
 
I was told by a well known machinist to use the motoman way on my brake in, however, I was too paranoid to use the brake in with nothing but hard driving. motoman brake in goes against everything in my nature for braking in a car. Personally I just let it get up to themp and check for leaks. If everything is idling good and not over heating start driving alittle bit and just dont sit at one RPM for too long. Go up and down a lot with the RPMs, no cruising! I wouldnt red line it either. But this is just my .02, I am not a ASE tech, just someone that just rebuilt my motor and is at 500miles with no problems. good luck!
Yeah I wasn't gunna redline maybe 4-5k then let it pull vacuum, then do that again in the next gear. what kind of oil did you use for break?
 
I rebuilt my motor and just used regular castrol oil and changed after letting it idle for 30 min. The main reason why people break in motors is because engine components used to not have the precision that we have now (Someone please correct me if I'm wrong). If you look at professional race teams, they build their motors and run them hard right away. I rebuilt mine and have about 500 miles on the engine now and it's running great. No smoking, leaking, or metal shavings. I have about 350 miles pf hard driving on it now too.

If you had your engine completely redone, you should be fine. Remember to torque your head studs down again after 500 miles. I do believe that is in the manual somewhere.
 
break the motor in based on what your intended driving behaver will be...
For example if your gonna drive the car hard most of it's life, use the motoman break-in method, if you plan on daily driving and no really hard racing use the standard method.

breaking in a new stock engine is really not going to net you much over stock hp/torque gain-wise or anything, I personally see the motoman break-in method more as one mans own opinion on how to break in a motor by no means is it the gospel.

The guy that invented the motoman method is most likely looking at each piston ring with a microscope.
which I guess is not a bad.idea, but this just means in English don't guess every spec on a re-built engine is up to snuff... know.

Also check the cylinder compression after the second or third oil change.

And don't forget anytime you change the oil, during break-in, change the filter as well, I recommend the Wix,Mobile1,K&N,STP,Bosch,purolator.

pretty much anything but Fram and the microgaurd brand.
 
SAE 30ND oil
motoman method
1500 rpm for 20 min (not idle)
6k rev limit for the first 100 miles
Keep it off the highway (the same rpm for extended periods isn't good)

Vary rpms a LOT, engine brake a LOT

Make sure it's not running too rich cause the excessive fuel can wash down the cyl walls. I ran mine at about 11.5:1 AFR on pump with reduced timing so I didn't have to worry about knock and broke it in with 12-15 psi and had it to almost 20 psi at 100 miles.
 
And with the oils: Change the oil after first 20 miles, then 50 miles, 100 miles 200 miles and you should be okey after the 600 miles.

True, good ol' cheap 30w ND dino oil for break-in oil to get them rings seated in easy.

If you use synth oils, thing will never get broke in correctly and properly.

DSM
 
I'm breaking in my motor right now. Only have 11 miles on it so far and still working out some leaks.

My machine shop has a great reputation. They gave me a racing break in oil called "Driven" (BR40). www.drivenracingoil.com. It has high Zinc and Phosphorus. He told me to change the oil filter after 20 minutes of operation and then change the oil at 450 miles. He also told me to stay away from synthetic until about 4000 miles.

I'm using the motoman method. I brought the car up to operation temp, checked for leaks and then went out for an immediate drive. I hit some good pulls in 1st, 2nd, and 3rd... Then down shifted the motor back to first and repeated the process. I've been trying to not exceed 5500 RPM'S yet. I'll eventually start to push the RPMS higher. The few leaks that popped up have kept me from getting more miles put on. I've read a lot of threads saying the first 20 - 50 minutes of operation are very important to seat the rings. So just sitting at idle can be bad for your motor.

Not sure I'm doing it 100% right but I'll let you know how my engine turns out.
 
^^ Interesting site posted above - quite informative to read and print out. Only thing I'd be concern is the break-in period after the first oil change until the 450 mile change using just the break-in oils and the motoman methods. I'd still be doing a couple of more changes in between just to be more safe.

True, long idle period is a big "no-no" on a break-in motor.

Why we never break in a motor on a constant speed is that after the break-in using this method, the motor only knows this RPM speed to be fully functional and other speeds will cause problems with oil consumption and performance.
 
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break the motor in based on what your intended driving behaver will be...
For example if your gonna drive the car hard most of it's life, use the motoman break-in method, if you plan on daily driving and no really hard racing use the standard method.

breaking in a new stock engine is really not going to net you much over stock hp/torque gain-wise or anything, I personally see the motoman break-in method more as one mans own opinion on how to break in a motor by no means is it the gospel.

The guy that invented the motoman method is most likely looking at each piston ring with a microscope.
which I guess is not a bad.idea, but this just means in English don't guess every spec on a re-built engine is up to snuff... know.

Also check the cylinder compression after the second or third oil change.

And don't forget anytime you change the oil, during break-in, change the filter as well, I recommend the Wix,Mobile1,K&N,STP,Bosch,purolator.

pretty much anything but Fram and the microgaurd brand.

This is a perfect cap on motoman vs normal brake in procedure. 1 thing though.. I would buy OEM filter from dealership they cost 6$ and its the better filter IMO
 
On my Evo and Dsm build...... Drive the bi*** like you stole it. If its built, its built. You dont want something coming loose that one time you hit the gas. Run it at stock boost for about 500 miles, then after that, turn it up and go. Like I mentioned, I do flat out runs to what my valve train could hold and once i left off the gas, I let it decel down from that certain rpm. I used the cheapest oil found at walmart for breaking in. I then continued to run brad penn 20-50 for its whole life. (I set my bearing clearances to handle 20-50 yearly.)

Not one engine I broke in failed, nor will any. The motors all have over 50k on them. And they are dd'd.
 
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I agree with Livedsm. I was nervous about break-in on my new motor but I just manned up and actually drove the car. A Lot of decel for first couple drives. Then about 300 miles in I got the car tuned. 45+psi of boost and over 1000 miles later and 20+ passes at the track, everything is still running strong with NO smoke.
 
breaking in a new stock engine is really not going to net you much over stock hp/torque gain-wise or anything, I personally see the motoman break-in method more as one mans own opinion on how to break in a motor by no means is it the gospel.

i couldn't respectfully disagree more.... this is a SHORT but CRITICAL stage in the engines life. especially if the valve cuts and rings/cylinder bore surface are new. the way the engine is broken in ultimately determines exact compression ratio, rev characteristics and how well the valves will seat and seal for the remainder of the engines life. on a turbo engine like ours we are lucky that we have extra force (boost) the make the rings (expand more) and valves seat (cut their own little groove in the cylinder and seat to match their circumference perfectly.) if the break in is hurried, you will end up with a mild polish on your cylinder walls.... not a good thing. you actually do not want the cylinder walls smooth as glass or the oil will have no retention to the walls and rings and you will get excess blow by and low compression as well as excess friction and heat. the "cross hatch" is put there to act as a nearly invisible sponge to retain oil as well as create a hydrodynamic wedge. (set a flat drinking glass on a smooth wet surface and watch it kinda hover and you will see ;) this effect is on all the pressurized bearing surfaces as well, that is how there is nearly zero metal on metal contact when engine is running ) not properly heat cycling the engine or not using the right viscosity oil (too slick like synthetic) will hinder these parts from creating their needed initial cuts where they need to be and just leave you with a smooth, pretty but useless surface. .... feeew and on that note , im done. oh,and someone mention not being an ase tech,... ASE master tech here. ;)
 
^ Good read above. True, take it a bit on the easy side (drive sane and normal, yet don't have to "baby" it...), yet doesn't hurt to give it a short power blip from time to time to give it some exercise so the moving parts can break-in to a perfect connection - and yet, not hurried.

Just use good break-in dino oils and a good stock of cheap filters to carry away the cuttings away from those moving parts.

I've seen high mileage block teardowns where one can still see the hone cuttings in the cylinder walls.

DSM
 
My 6 bolt will be going together and into the car soon and after all the reading I've done, I'm definitely leaned towards the motoman method for the most part. I'm not going to take it out and beat it to redline in the first 5 minutes, but I am certainly going to 'excersize' it via accelerating/engine braking to get plenty of vacuum/pressure in the cylinders.

Now... this dino oil... it's just oil high in zinc and phosphorus, right? Is it always diesel oil? Also, are FRAM filters really all that bad? I've used them on my Hondas for years and they love them.
 
Break-in for a stock Ford Focus, for example, will be different than break in on a 600hp 4g63. The PTW clearances are most likely tighter on the 165hp(est) Ford than the fully built 4g engine.
This is my understanding. Thus on a looser, higher hp build, you want to pound on it as soon as it hits 160* or so. Dont drive out and floor it until it is up to operating temp. Just wg pressure for awhile.

Motoman gets my vote: for a built motor, that is


Edit: I DID use motoman's method. Results after 4500 miles...hard miles cyllinders 1,3,4 all at 185psi. Less than 5% leakdown.
Cyl 2? Thats a whole 'nother story that had nothing to do with the break in LOL. Gotta do w a machinist
 
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Well thanks for all the Input guys! Sorry I've been awhile for the site for a bit. But like I sai it's a stock rebuild, I'm gunna get on it fool around but I'm not gunna be slapping a huge turbo, fuel upgrades and tuning it for 30 psi. Just some to cruise around in till I can later tear the engine down and really build it
 
Now... this dino oil... it's just oil high in zinc and phosphorus, right
"Dino"oil is a term used by mechanics of any oil that originally came from the ground and so nicknamed since oil came from dinosaurs. Actually, the term would be just regular oil since synths came into play.

Just fun to say "dino" oils. And good cheap recycled dino oils are great as break-in oils since they're not going to stay in the crankcase very long before it wears out, thus will not cause any damage...and it's cheap on the pocketbook.

Thing about FRAM filters: Yes, quite cheap filters to use, but they do alright in numerous oil change cycles - like the recommended 3mo/3000 oil change. Just don't keep them on past the recommendation period..and this goes for those FRAM built "Microguard" filters sold by O'Reillys.

I've used FRAM filters for years with no issues either on my other vehicles that I've owned, but with having this turbo setup, I'm using NAPA Gold 1381 filters which are made by WIX along with synth 10w30 oils.

There are two different kinds of dino oils: paraffin based (Quaker State, Pennz -any oil from Pennsylvania wells ) and mineral based oils ... and the two simply do not mix together since paraffin is a wax and if you put a paraffin based oil in with mineral oil, you get some nasty results from the mixing.
 
Mr. Buschur seems to disagree that breaking in a motor is required at all. I guess I understand the logic behind it, but I'm inclined to agree with him, that engines do not need any extra care right off the bat. I would love to see empirical evidence that proves engine performance and reliability are heightened with popular break in methods.

If something is going to go wrong, then thats just going to happen and there is not much you can do about it other then takin 'er easy for the life of your engine. But, as always, your mileage may vary.
 
i couldn't respectfully disagree more.... this is a SHORT but CRITICAL stage in the engines life. especially if the valve cuts and rings/cylinder bore surface are new. the way the engine is broken in ultimately determines exact compression ratio, rev characteristics and how well the valves will seat and seal for the remainder of the engines life. on a turbo engine like ours we are lucky that we have extra force (boost) the make the rings (expand more) and valves seat (cut their own little groove in the cylinder and seat to match their circumference perfectly.) if the break in is hurried, you will end up with a mild polish on your cylinder walls.... not a good thing. you actually do not want the cylinder walls smooth as glass or the oil will have no retention to the walls and rings and you will get excess blow by and low compression as well as excess friction and heat. the "cross hatch" is put there to act as a nearly invisible sponge to retain oil as well as create a hydrodynamic wedge. (set a flat drinking glass on a smooth wet surface and watch it kinda hover and you will see ;) this effect is on all the pressurized bearing surfaces as well, that is how there is nearly zero metal on metal contact when engine is running ) not properly heat cycling the engine or not using the right viscosity oil (too slick like synthetic) will hinder these parts from creating their needed initial cuts where they need to be and just leave you with a smooth, pretty but useless surface. .... feeew and on that note , im done. oh,and someone mention not being an ase tech,... ASE master tech here. ;)

My main point was don't expect to gain 30+hp over a regular break in by using the motoman method.
breaking in an engine is not like installing bigger turbos, or raising the boost.

because the engine rings seal better it will hold boost better, it wont raise it for you.

but I do agree, that breaking in an engine [correctly] is critical to reliability and over all engine life.
 
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