Production engine bearing assembly lube?

[jccaclimber]

How long until everything is 'broken in'? Because any goo put in the bearings at assembly is (hopefully) gone within seconds of achieving oil pressure. So its not there until everything is broken in. And if you're thinking a film of it mixed in with 4-5 quarts of oil is doing -anything- ......ah, not so much.
'Broken in' I think went out with the model A engines that needed to be run in on a stand using an electric motor because they were 'tight' due to limited semi-precision tolerances achievable back in the day. Since the 1960's if an engine was going to survive, it was 'good to go' and not much breaking in needed. Modern engines are quite precise and 'broken in' right from modern production line assembly tolerances.

Having worked at multiple tier 1 automotive parts suppliers I need to add a disclaimer to this. Are parts to drawing and functional? Yes, as you said. Are things clean and free of damaging particulate, fully mated, etc? No. I highly recommend a short oil and filter change interval on a brand new vehicle. It’s not the big particles that cause damage to the bearings, it’s usually the tiny ones.

 

[dkmc]

Having worked at multiple tier 1 automotive parts suppliers I need to add a disclaimer to this. Are parts to drawing and functional? Yes, as you said. Are things clean and free of damaging particulate, fully mated, etc? No. I highly recommend a short oil and filter change interval on a brand new vehicle. It’s not the big particles that cause damage to the bearings, it’s usually the tiny ones.

And lets all clap for full flow oil systems, filter equipped. Filtered oil quickly flushes the system, no worries. Dirt in the internals is a given, all oil in the galleries (gallies?) is filtered before hand.
There are videos now of tear downs with 200K+ miles, rod and mains look 'as new'. No copper or under layer showing on inserts.

 

[GregSY]

How long until everything is 'broken in'? Because any goo put in the bearings at assembly is (hopefully) gone within seconds of achieving oil pressure. So its not there until everything is broken in. And if you're thinking a film of it mixed in with 4-5 quarts of oil is doing -anything- ......ah, not so much.
'Broken in' I think went out with the model A engines that needed to be run in on a stand using an electric motor because they were 'tight' due to limited semi-precision tolerances achievable back in the day. Since the 1960's if an engine was going to survive, it was 'good to go' and not much breaking in needed. Modern engines are quite precise and 'broken in' right from modern production line assembly tolerances.

I don't think modern engines don't need to be broken in. There's a lot written about how great modern production/machining is...but I think half of that is hooey and half of it is meaningless, leaving only about 50% valid. But machining has not much to do with breaking in an engine. Regardless of how well an engine is machined, it should be given run time for all the shiny new parts to properly get used to their new neighbors. Rings, especially, need to seat. Lifters, rocker tips, etc. all need to seat.

When I bought a Hellcat, the first 500 miles were purposely limited by the factory....the car was only able to be driven on the 'black key' which is good for 500HP and had lesser throttle response. Once it hit 500 miles, the 'red key' was enabled and it could be driven at its full potential. That's one example of even the factory recognizing the need for a break-in period.

 

[GregSY]

Having worked at multiple tier 1 automotive parts suppliers I need to add a disclaimer to this. Are parts to drawing and functional? Yes, as you said. Are things clean and free of damaging particulate, fully mated, etc? No. I highly recommend a short oil and filter change interval on a brand new vehicle. It’s not the big particles that cause damage to the bearings, it’s usually the tiny ones.

All true, but not the super tiny ones. The (modern) theory behind oil filtration is you need the filter to catch any particles large enough to cause damage, but if they are small enough to fit between running surfaces, it's better to let them be suspended in the oil and (presumably) drained when you change the oil. This is why a good oil filter will have a micron rating (I don't recall exactly the number) of around 50 microns. You can buy oil filters that go finer, but they greatly restrict the oil flow and also have the tendency to remove stuff from the oil you don't want removed....additives like zinc, dispersants, etc. I always am amused when someone brags that their oil comes out as clean as when they put it in...that's not a good thing.

 

[eKretz]

Yeah there's no question that rings need to seat, just as one example. Just like nothing is ever perfectly rigid, nothing is perfectly round or even the same in not-roundness (for instance, ring OD vs. cylinder ID), not to mention any distortion caused by combustion pressure.

 

[gbent]

Interesting about low power break in of gas engines. Diesels are to be broken in at full power. Instructions will usually say to keep idling to absolute minimum, if repairs or adjustments are necessary, shut off engine if possible. Run time should be over 2/3 power if possible for first couple of hundred miles.

Otherwise, break it in as you will use it.

 

[GregSY]

The reason, I think, is that the combustion pressure that comes with load is used to help force the rings outwards which promotes seal and break-in. High RPM is not good for break-in, but high loading is, or can be.

 

[eKretz]

Yeah, break in during driving is generally recommended as lots of heavy throttle and engine braking, but at lower RPM; lugging/loading the engine and creating high cylinder pressures without high piston speeds, such as giving 'er a little extra throttle at low speed in top gear. Not easy to do with automatic transmissions unless they have a full manual gear selection, which most don't.

 

[jccaclimber]

All true, but not the super tiny ones. The (modern) theory behind oil filtration is you need the filter to catch any particles large enough to cause damage, but if they are small enough to fit between running surfaces, it's better to let them be suspended in the oil and (presumably) drained when you change the oil. This is why a good oil filter will have a micron rating (I don't recall exactly the number) of around 50 microns. You can buy oil filters that go finer, but they greatly restrict the oil flow and also have the tendency to remove stuff from the oil you don't want removed....additives like zinc, dispersants, etc. I always am amused when someone brags that their oil comes out as clean as when they put it in...that's not a good thing.

It's been about 4 years since I was involved in oil life and durability studies, but the numbers I saw at the time disagreed with this.
Particles substantially larger than the bearing clearance can cause damage, but often have another way out of the system that doesn't require them to pass through a small gap, or they get stuck and wear until they fit through. Particles just a tiny bit smaller than the bearing clearances act like lapping compound and cause slow but continuous damage. You would love to filter these out, but as you said it isn't really practical. The pressures required to do this aren't practical and anyone who has had to work with single digit micron filters knows just how quickly they plug. As a result (and also for other reasons), you simply need to change your oil periodically.
Related to this, one benefit of the random sizes in oil filters is that a new filter will have some smaller holes that will catch these small particles. As that happens the tiny holes plug and all of the oil starts flowing through the larger pores. At that point the backpressure hasn't changed much as the big holes haven't plugged, but the ability to filter out these tiny particles is greatly reduced.

For anyone who thinks small particles don't damage engines, I have a teaspoon full of 5 and 10 um aluminum oxide lapping compound you're welcome to try out.

 

[triumph406]

My Dad ran the Petters factory in the South of England. The small Petter engines after the first 30-60 seconds of running were wound up to almost full load for 15 minutes. They found a gentle break in didn't allow the rings to seat and they smoke and consume oil like crazy.

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I would think a good quality grease would survive for years, assuming the engine hasn't been run, and there's no contamination or moisture present.

When I was working on small UAV's there was a small German UAV that used a small diesel engine. The UAV as loaded into a tube with the wings folded. The UAV in the tube was expected to be able to be pulled out of the tube, attached to a power source started up and flown. Even after 20 years of storage. Evidently they expected the grease used in parts of the engine to be serviceable after 20 years.

 

[projectnut]

I've used Honda Engine Assembly Lube when putting new rods, pistons and rings in chain saws. It also works well as a lubricant for dead centers.
Here's a link to some available on eBay. It seems more expensive now than when I was buying it a couple years ago. The last time I bought a case of 12 tubes, and still have half of it.

Genuine OEM Honda Moly Paste M-77 Assembly Paste Grease 08798-9010 Update 60 | eBay

Find many great new & used options and get the best deals for Genuine OEM Honda Moly Paste M-77 Assembly Paste Grease 08798-9010 Update 60 at the best online prices at eBay! Free shipping for many products!

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[Dan from Oakland]

I have always used the Sealed Power assembly lube in the small sqeeze bottles. It does not dry out and get thick like grease or lubriplate. Vintage engines sometimes sit for several years while the owner gets the rest of the car finished up, so this has been a concern of mine on various occasions. The Sealed Power stuff seems to be ok in this regard.

 

[CarbideBob]

So some thoughts or questions to ponder.
What is used by those who build 500-4000 engines per day?
What is the "break-in" period needed for 300,000 mile mean time to failure?
How long to "ring seat and seal"?
Why do the engine plants no longer even start and test all the things coming off the line?

If you buy a new car the engine gets fired up for the very first time as the fully assembled vehicle rolls out.
At this point it must, must, must meet all emission requirements and work correctly.
Yes there is often a cold test to make sure it at least rotates, pumps air and makes no funny noises.

In the past there was most certainly a break in needed to allow all the parts to become "friends".
That is gone now... why?
IMO if built correctly the break in period is 1 to 2 minutes or less.

I my past I put the wrong cam in 427 Chevy. Seems there was a grooved and non-grooved at the ass end and I did not know this.
Not sure why now but I pulled a valve cover after a while. No oil to the rockers up top. None...
The only way it survived was my assembly mix of grease and STP.
My carbide insert grinders had a HSS cam and a carbide plate follower.
One would think the cams go bad first. No... since there are 200+ different cams for all sizes and shapes. The carbide pad would wear and puck up the B dimension.
Fought this. It is machine downtime to regrind this pad and when to do it.
What the heck this worked in my car motor so lets try it here. Ten times the life over way oil.
Bob

 

[gbent]

STP is really slick stuff. Used properly, it can be very valuable in drawing dies.