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This originally came about because of cast-iron rings.
With oil so advanced now, can freshly built engines be broken in with synthetic?
- Thread starter Nicasio
- Start date
There was a discussion about this last month.
Factory fill is different from the oil the factory uses for the first start. I believe, and it makes sense to do so, that the first start oil is a very special brew.
Personally, I would (and still do) use a 30wt mineral for the first start on a fresh rebuild. I have rebuilt a few.
There was documentation at one time detailing initial break in with syn. vs mineral, but the oils were vastly different then.
It is not an old wives tale. It was valid at one time, and I believe still is today.
Factory fill is different from the oil the factory uses for the first start. I believe, and it makes sense to do so, that the first start oil is a very special brew.
Personally, I would (and still do) use a 30wt mineral for the first start on a fresh rebuild. I have rebuilt a few.
There was documentation at one time detailing initial break in with syn. vs mineral, but the oils were vastly different then.
It is not an old wives tale. It was valid at one time, and I believe still is today.
Group III synthetic is actually becoming the preferred base oil for dedicated break-in oils as the additive response is better than group I/II.
I'm heavily anti-supplement, even the ones that actually provide something beneficial like ZDDP supplements. If your oil needs a supplement, you're using the wrong oil.
Most OEMs state no break-in oil or procedure is necessary. They also deem a quart of oil consumption in 1,500 miles as "normal" so take that for what it's worth.
I'm heavily anti-supplement, even the ones that actually provide something beneficial like ZDDP supplements. If your oil needs a supplement, you're using the wrong oil.
Most OEMs state no break-in oil or procedure is necessary. They also deem a quart of oil consumption in 1,500 miles as "normal" so take that for what it's worth.
I completely rebuilt my '58 Ford I6 in '77. Straight in went (original) Mobil1.
Breakin no longer needed on new engines
Many of the synthetics of the early & mid 70s (Mobil 1 excepted) were based entirely on esters. With that much competing polarity and depending on engine design, these oils sometimes delayed the ZDDP from establishing its protective film in newly rebuilt engines during break-in, leading to cam lobe wear. One study in engine sequence tests showed that the cam lobe wear all took place in the first two hours of the test, after which the ZDDP won the competition. It rarely manifested as a field problem because engines were broken in with factory fill mineral oil. This probably led to the recommendation to not break in an engine with synthetics.
Thank you for posting actual facts.
"Synthetic" can mean so many things today, but I would avoid ILSAC lubes with their RC slickifiers and for "on the cheap" run a JASO MA2 4T shared sump superbike oil or an SAE 30 with the cam mfr supplied break in additive - if you are not buying a formulated break in oil.
I would run break in oils during initial start and cam wear-in and also on the second sump. But always check top end for proper lubing during initial priming - you could have a cam bearing clocked wrong or machining junk in the galleries. If you can drop the pan (means don't go nuts with Permatex gasket maker) do that and clean it out and the pickup. Replace oil filter.
Regular passenger car off the lot? I think protracted wear-in is always a possibility and a gamble but what really are your choices in 20 grade or lighter oils? Here your driving would be most critical. Don't rev the thing over 3500 and drive it normally or moderately aggressively right off the lot (if your 'normal' is "Auntie Tilda off to Church"). Increase revs as you add on the miles but I would keep it under 4500 until you are over 750-900 miles.
Our classics and hotrod rebuilds seem to do well - but none of them have high miles most are early gen SBC, a couple are vortec.
Modern passenger cars? Most in this household in the past two decades don't make it to 65K. I recall one did - a '17 Crosstrek with CVT.
What? Wait! Why?
Could be that steep hill? Start the car, wait 1 or 2 mins, then head off down the hill - immediately severe nose down attitude at high idle with cold oil for 100ft. Foaming and starvation? At least 4 months of this through the Winter.
O.K. all reading this just put it in the IGNORE pile, lol.
I would run break in oils during initial start and cam wear-in and also on the second sump. But always check top end for proper lubing during initial priming - you could have a cam bearing clocked wrong or machining junk in the galleries. If you can drop the pan (means don't go nuts with Permatex gasket maker) do that and clean it out and the pickup. Replace oil filter.
Regular passenger car off the lot? I think protracted wear-in is always a possibility and a gamble but what really are your choices in 20 grade or lighter oils? Here your driving would be most critical. Don't rev the thing over 3500 and drive it normally or moderately aggressively right off the lot (if your 'normal' is "Auntie Tilda off to Church"). Increase revs as you add on the miles but I would keep it under 4500 until you are over 750-900 miles.
Our classics and hotrod rebuilds seem to do well - but none of them have high miles most are early gen SBC, a couple are vortec.
Modern passenger cars? Most in this household in the past two decades don't make it to 65K. I recall one did - a '17 Crosstrek with CVT.
What? Wait! Why?
Could be that steep hill? Start the car, wait 1 or 2 mins, then head off down the hill - immediately severe nose down attitude at high idle with cold oil for 100ft. Foaming and starvation? At least 4 months of this through the Winter.
O.K. all reading this just put it in the IGNORE pile, lol.
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Yeah - I still have an old school break in procedure - more to it than just the engine. The last thing I had burn oil was a 17 year old Dodge truck …
So you're saying engines are filled with a special oil, fired up and ran, then that "first start-up" oil is drained and another oil is installed? Haven't heard this before - got any links to more info about this? Where did this claim come from?
I read that article in HotRod. April of 96 I think.
Looking at oils from the factory..they seem to be very high in Moly
Yes, that is what I am saying. I used to want to provide links, etc, but on BITOG I found it to be generally a waste of time. If you, or anyone else are truly interested, you can certainly find it yourself. Not meaning to sound snotty to you, even though I did.
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Sounds like Porsche just fills the engines with oil, runs them up without firing them for an initial checkout, then puts the engine in the car and runs the car on a chassis dyno. Doubt they change the oil before it leaves the factory. Some of the randomly engines pulled for the dyno room for extensive testing probably get and oil change, but wasn't specifically discussed, so who knows. Of course, every factory can do things differently, but to say all engines use a different special oil for the "first start" doesn't seem to be the actual case from my searching.
Engines are not really "Broken in" at the factory
Engines are not really "Broken in" at the factory
www.2addicts.com
"At the end of the assembly line, the engine is filled with Mobil 1 Synthetic Oil. Each engine is then dry run (without fuel), pressure tested and checked for leaks. Every car coming off the production line is also run on a rolling road dyno. This enables all cars and engines to be tested at highway speed before they leave the factory."
You can find more than that posting. There are factory tour stories going back 25-30 years and more that confirm what I say. Even for large, not niche manufacturers. It wont be on the first 10 pages of Google, I can tell you. (We are losing our minds and our knowledge to the first 10 pages of Google).
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What they did 25-30 years ago compared to what they do now is most likely not the same thing, as shown in the Porsche factory tour description. You are free to post up your links, so I'm not going to try and find some nebulous link describing what was done 30 years ago.
And this is why I don't bother. "Going back" means present day to 25-30 years ago.
Like I said, if anyone cares enough to look, they can find the info.
Like I said, if anyone cares enough to look, they can find the info.
I've found more than a few instances saying engines are ran un-fired to check them out (as described in the previous link). It's a more efficient way to check the assembled health of the engine before putting it into the car. And pretty much all assembled cars are ran on a chassis dyno for a final checkout. They aren't going to use special "first fire" oil and change the oil and filter after the engine has only been run a few minutes. That would be unnecessary with modern engine manufacturing and assembly, and would a big waste of resources. The oil filter is on an engine for a reason.
No, "first start" oil is a thing. I doubt they are using a standard oil filter either. Probably a fitting that goes to the test stand oil system.
First start sheds a lot of junk. A lot. Modern engine or not. Think about a small modern filter dealing with that, and a 10K (or more) initial OCI.
Does that make sense? No.
First start sheds a lot of junk. A lot. Modern engine or not. Think about a small modern filter dealing with that, and a 10K (or more) initial OCI.
Does that make sense? No.
