Running in a new car...does the following make any sense?!

[Lankan]

Just read the following post on Pistonheads in response to a query about changing oil ahead of the recommended service interval. The following post was by someone purporting to be an 'Automotive Engineer', and since I am not sure whether it was posted in jest, as I had never heard such a thing before, I thought I would check with those of you who fettle engines and/or are mechanical engineers.

"Actually the oil filter is designed to let through shavings that help run in/hone the engine. If you drain the oil early, those are literally down the drain and usually won't come back... That said running in usually ain't very critical apart from bedding the piston rings perhaps."

The said car does not appear to have a running-in service in its maintenance schedule. As such, what do you think?

 

[Jamesv6]

No idea tbh. I think one of my handbooks said drive carefully for the first 700 miles

So he is suggesting a load of crap shards have a job to do!

 

[9810588]

Metal shavings help honing the cylinder? :rofl:

Because it is possible to precisely control the size and shape of the metal shavings, and they won’t block the oil spray nozzles, yeah?

I do follow the typical recommendation not to drive hard the first 1500km and vary the speed and load a lot, rather than monotone freeway driving, during that 1500km.

 

[Kett]

Not entirely on topic - but I dodged a bullet by changing the oil/filter on my VW van every 5k / 6months.
Turns out there was a design fault on the aluminium vanes on the EGR valve which was spewing fine ‘aluminium oxide’ into the engine oil.
My business partner, in turn, followed the manufacture recommended service protocols (2 year/ 20k miles) and had catastrophic engine failure at 65k miles.
£8,800 bill. This was partially sweetened by a VW goodwill gesture... lol

Moral of story: change the f’ing oil!

 

[Ren5Clio]

I would recommend when running an engine in that it's a good idea to increase the revs gradually to say 4000rpm max (no heavy throttle application) & off then come fully off the throttle (engine overrun) until the revs drop down again. Do that twice & then repeat every 1/4 mile or so for the first 1 hour of running. This allows oil to move in between the oil control rings to keep the bore lubricated. If your driving roads are very "on off" throttle anyway you'll be ok, it's long distance drives at a constant rpm (motorways) that is not so good for running in.

It's also very important to use a mineral oil (like Mobil Super 1000) when running in, modern fully synthetic oils have too much friction reduction additives which is not what you want when trying to bed piston rings into the bores. It's imperative not to glaze up the bores when running in as a good piston ring to bore seal is imperative for good compression (power / economy) & longevity.

After the first 1 hour of running at 4000rpm max keep the rpm under 5000rpm for another 2 hours of running & no heavy throttle application. After that 3 hours of running you can drive to higher rpm.

Change the oil & filter after the first 1000 miles, drain the oil and re fill with mineral oil again & run for another 2000 miles then flush out the oil and go to the semi / fully synthetic oil of your choice.

 

[Lankan]

So, it seems that no one has heard of "...the oil filter is designed to let through shavings that help run in/hone the engine", which is in line with my understanding, in that the purpose of an oil filter is to prevent any crud getting into the engine block, and one is also recommended to use a magnetic sump plug to trap any metal fragments at the bottom of the sump.

Fully agree that any new engine needs to be broken in according to the manufacturers' guidelines. However, not every manufacturer recommends an oil change after running in is complete, and some use the same grade of engine oil pre & post break-in. For example, BMW does have a running-in service for its M cars, which must be carried out between 1,000 and 1,200 miles, but it seems that they do not use mineral oil or semi-synthetic oils, or any other running-in oils, from the factory. "No running-in lubricants are used in these components between build and 1,200 miles service."

Lotus, on the other hand, do and mandates that for the first 600 miles one needs to keep engine revs below 4,000 rpm and that an oil & filter change is done between 1,000-1,500 miles (at the 'After Sales Service'), where the mineral oil is replaced with synthetic. Failure to keep to this schedule invalidates the warranty.

Below is what I find in [v6plaque]002[/v6plaque]'s owners manual:
"Petrol version [Was there a diesel version of this engine?]
For the first 625 miles (1000 km) do not exceed 80 mph (130 km/h) in the highest gear or 3000 to 3500 rpm. On completion of 625 miles (1000 km) you may use your vehicle normally. However, it is only after 1875 miles (3000 km) have been covered that you may reasonably expect full performance."

No oil change recommended or mandated for the Vee.

So, in summary, the Vee was built in Sep 2003, the BMW Z4M was built in Aug 2006, the Exige in Sep 2010, and they have very different running-in procedures, and the need for an oil change, or not ad the case be, after that.

 

[MarkK]

Letting metal shavings through the filter? Sounds like a load of nonsense to me!

The main running-in process which I think still holds true is to use a light throttle and don't rev it too much.

I've rebuilt a few engines in the past couple of years and the machining and balancing is so much more accurate now than it was when careful running in was required. That said, you still need to use a simple oil like a straight 30 grade non-synthetic to bed in the rings. Modern oils are so good they will coat the bores with a protective layer so that the rings cannot bed in properly. There are a lot of re-built engines running that are very smoky for this reason.

That said, I don't think that people re-build modern engines as they don't usually need work until long after the rest of the car is scrap.

 

[DaveL485]

1)Shavings...LOL....brilliant. What a crock of shite.

2)This is an excellent article by Dave Baker of PumaRacing

>>>Taken from the Puma Racing site before it vanished, written by Dave Baker.

Probably one of the most argued about topics in engine theory you'll ever come across. Everyone has their own opinion ranging from the 'give it death from the start' to treat it with kid gloves for thousands of miles before using it hard. In fact running in an engine is not a single process. The various internal components take different times to reach full efficiency and require different approaches to make sure they bed in properly.

The first item to consider is the oil used. In years gone by you could buy running in oil which was basically very cheap oil with low friction reducing characteristics. When engines were hand carved out of solid blocks of cast iron by workmen in flat caps using hand files and paid a shilling a month this might have been a good idea. Nowadays any half decent engine machining should be of a high enough quality that comparatively few high spots actually need to be worn off the various mating components. Using a fully synthetic oil from the start is generally considered to be a bad idea because it needs some metal to metal contact to bed things in but component loadings are so high on modern high output engines that a very cheap oil is a false economy. My advice is to use a medium to high quality non synthetic oil and the best oil filter you can buy. The higher the engine output the better the running in oil you should use. Turbo engines generate very high temperatures in the turbocharger and the last thing you want is something that will bake into carbon the first time you start the engine up.

Next thing to consider is running in the camshaft. This will mainly be applicable to pushrod engines or those using overhead cams and rockers. OHC or DOHC engines with flat faced buckets under the cam lobes are much less prone to cam wear problems. 15 minutes at 2500 rpm with the car on the driveway is the way to run cams in. The main thing is never let them idle for the first few minutes. All this is considered in more detail in the article on running in cams.

Now you're ready to take the car out on the road and bed the piston rings in. To do this requires several brief applications of full throttle in a high gear to generate high cylinder pressures and force the rings against the bore walls. Put the car into 4th or 5th at 1500 to 2000 rpm and apply full throttle for about 10 seconds. Coast along for 30 seconds to dissipate any heat generated and repeat. Do this ten times. It should take about 10 minutes and maybe 5 miles if you don't have too many other cars up your chuff trying to get past.

By now you've already worn off more than 90% of the high spots on the various bits that contact each other. However friction levels inside the engine are still fairly high compared to what they'll eventually settle down to. The next stage is to gradually build up throttle usage and rpm limits. This can take place much faster than many people realise. Drive for 50 to 100 miles with gradually increasing throttle usage and rpm. By the end of this time you should be using full throttle and high rpm for brief periods provided fueling and ignition settings are already optimised. In fact on the road it will be hard to hurt the engine because you'll have to back off for a corner, speed camera or plod car long before you melt the engine. On the track, or maybe on a motorway you might be able to use the engine hard enough to hurt it in the first few miles.

Listen to the engine. Does it feel tight and not want to rev or does it feel free? Hopefully it should sound quite happy by now.

99% of the high spots are now worn off after 100 miles and it's time to change the oil and filter again. Use a high quality non synthetic oil. You can leave this in for either another 1000 miles or until your normal oil change interval. At that point swap to your long term oil which might be a fully synthetic if the engine and your pocket warrants it. The engine should be happy to take pretty much whatever you can throw at it after 100 miles if it's been built right. What you might want to consider is that by the time you've pottered about with your new engine for 3 hours (that's probably at least 100 miles) at say an average of only 3000 rpm it's already done over half a million revolutions! Yes I did say half a million. 3 hours x 60 = 180 minutes x 3000 revs per minute = 540,000. How many times do you think one component with a miniscule high spot has to operate against another component before the high spot gets worn down?

If the engine has been modified it might require alterations to the fueling or ignition timing. Don't use it too hard yet if there's a possibility these might be way out. Get it to a rolling road and have it set up properly.

Over the next 1000 or more miles the friction levels inside the engine will continue to fall as the bores glaze up. The harder you use the engine the faster this will happen. Drive like your granny and it might take 5000 miles before the engine is fully loose. It won't blow up because it's not fully loose if you use it hard but the power will continue to increase as the friction levels drop. Also the combustion chambers carbon up which raises the compression ratio slightly and improves thermal efficiency as the carbon acts as an insulator. You might see another 2% or 3% power once the engine is really loose compared to the first run on the dyno after the initial break in period.<<<<<

 

[rustedandrotten]

What he doesn’t cover is the need to stress components such as crank and also the need to work harden items, this is equally important as polishing high spots, if not more so if you want the engine to survive!

 

[Lankan]

Interesting article. thanks Dave for posting.

What he doesn’t cover is the need to stress components such as crank and also the need to work harden items, this is equally important as polishing high spots, if not more so if you want the engine to survive!

Simon, what is the best way of achieving the above?

Below is the break-in procedure recommended by Toyota for their new 3-cylinder, 1.6-litre Turbo engine (G16E-GTS) that puts out 257bhp from the factory, but where some Japanese tuners have already taken this up to 350bhp without making any changes to the block or any internals.

 

[ed_harland]

Sounds like sensible advice