Is that what the OEs do before cars are delivered to the dealer?
Best engine break-in procedure?
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Drive it like you intend to drive on a regular basis. 5W30 or 10W30 for 500 miles then, change the oil and filter.
I would recommend NOT using a Fumoto valve on an EJ. The valve hangs too low off the side and while extremely unlikely, if the lever were to be bumped by debris, you stand to lose enough oil before the oil warning light and suffer damage. If you want an easy drain, use Stahlbus or Valvomax.Again, while this particular instance could be construed (in my case) to a Sunwest 2.5L SOHC EJ251 "Enhanced short block" https://sunwestautoinc.com/product/subaru-ej25-short-block-2-5l-sohc-1999-2005/ mated to some Subaru Reconditioned Non-EGR heads that should be for it, and with Six Star Revised MLS gaskets for the mating of...
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And of course, all new timing belt kit and other gaskets ready to go... - I have not yet viewed the information Sunwest has sent over about "how best to break it in." I thought I'd ask here. @Trav has given me a great lead on two 10W-40 mineral and high zinc break-in oils to run.. however, I still have questions (and again, if this is for "all engines" cool, please specify in your reply
1. How long to run break-in oil for?
(Preliminary research seems to suggest 100 to 200 miles "should be okay," yay or nay?)
2. How to drive during break in? Everything I have heard says to me moderate/hard on the throttle and do a lot of letting the engine coast down to speed, keeping an eye on temperature or maybe short runs (again, how long? Speeds? Highway, like an hour blast varying it like 65 to 90 for short times one way then letting it sit, or two hours of same, moderate to high RPMs.. how???? Highway cruising speed can easily be about 80 and a little faster than that sometimes. Would that be a good environment? Or not maintain same speed...)
3. Engine break-in oils help specifically with optimal ring sealing for highest compression, moreso than a regular "non synthetic" oil which this board has essentially taught me doesn't quite exist? Group 1, 2, 3, 4, 5 or Roman numerals thereof, every other thread seems to touch on this......
4. See questions 3, it's worth it to buy that oil and run it for.. ~200 miles, or how long, see question 1?
5. Any engine break-in oil that isn't a 10W-40?
6. Is it OK to use an xW-30 (like, more than likely, HPL No VII 5W-30) after using break in oil? I'll have the Fumoto valve on...
7. When is the engine broken in, when can normal oil be used?
@Trav recommended me one of these two: (so I'm inclined to purchase one of these two. I have a new catalytic converter ready to go, as well, since the old one has been flooded with coolant
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Driven Racing Oil 03706 Driven Racing Oil BR40 Conventional Break-In Motor Oil | Summit Racing
Free Shipping - Driven Racing Oil BR40 Conventional Break-In Motor Oil with qualifying orders of $109. Shop Engine Oil at Summit Racing.www.summitracing.com
I’d run the break-in oil 1000 miles, but if your shortblock was prepped correctly, the rings will be as sealed as they’re ever going to be by maybe 50 miles. Those years of engines were SL/SM, so as long as you’re not burning oil, a high zinc/phosphorus oil is no worry.
Trav has a bunch of good advice above as well.
I imagine. It takes about 20 minutes at 2,000 RPM for the lifter (or follower, or whatever) and cam to break in. In the old days, flat tappet lifters would slowly rotate relative to the cam lobe and smooth out all the asperities.
At idle, the lifter wouldn’t rotate, and could wear in badly, with grooves, which would quickly destroy both lifter and lobe.
Roller follower on a modern OHC engine probably doesn’t need this. But a shim/bucket arrangement certainly does.
LOAD THE RINGS is my priority. I got this from Mario Andretti's engine builder 40+ years ago. He was kind enough to talk to a punk kid on the phone ( for 10 minutes) asking the proper way to break in a motor. Get timing FAST ( points still a thing back then) get it up to temperature, find a big hill put your foot into the brakes in second or third gear mid rpm and "load the rings" this is your #1 mission on a new motor. He said to do 8 to 10 runs up the hill or road if no hill is available. He said you have a very very small window of opportunity to get the rings broke in properly. He said we can do this on a dyno easily. In the car break-in, it is a harder issue with your location of a city or country road. He said just worry about loading rings as soon as you can. Of course using the brake to help put resistance into loading is all but gone with todays cars with the computer killing the throttle. So now it is 3/4 throttle in the beginning then later in the loading to full throttle acceleration without exceeding 4,500ish rpm on a hill if you can. Adding the brakes made a huge difference to this procedure. Back then I built 5-6 street/race motors in our car club and all lived with no cam/lifter issues going by what Marrio's engine builder told me years ago. He also told me to dump the oil and skip the filter after coming back from the ring loading run.
Drive it like you stole it. Thats just me.
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JHZR2
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You should know how much of the head was shaved. As far as I understand, thicker than OE is for making up differences in deck or head material removal to keep compression consistent.
Just drive it. Take it easy for a couple hundred miles and then drive it like you normally would. Change the oil at 1k then again at 3k using decent oil. Then drive it however you want for the rest of its life.
It isn't a formula 1 engine or super high performance engine. It is a rebuild with remanufactured parts. No special procedure required.
If you feel like following a procedure...follow whatever Subaru says to do in the owners manual.
It isn't a formula 1 engine or super high performance engine. It is a rebuild with remanufactured parts. No special procedure required.
If you feel like following a procedure...follow whatever Subaru says to do in the owners manual.
The cylinder honing and piston ring selection from new OE and rebuilt can be very different. Plateau honed using up to 600 grit and low tension rings the OE vs the 220-280 grit commonly used by machine shops are a different animal when it comes to break in.
Six Stars are made by Cometic.
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I read that the best way to break an engine was to pour 5 quarts of sodium silicate into the engine. Or that's what they did in 2008.
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He's talking about Cash For Clunkers. Seems to have been 2009
Car Allowance Rebate System - Wikipedia
Some Maserati Quattroportes ended up getting "recycled" in that program. These
That Short Block should be coming today, by the way.
I'm most inclined to do what @Trav suggests. Here is what Sunwest days to do.
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