Fresh engine break in procedure?

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timk
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Fresh engine break in procedure?

Postby timk » Fri Mar 23, 2012 11:33 am

What do you guys know about breaking in the rings on a fresh engine?

I have heard to let the thing warm up to temp but not idle excessively, then go for a drive and get the revs up (loaded but not in boost) to around 5-6 grand, then let the car pull high vac through engine braking. Do this a handful of times then change the oil after about 20 km, followed by another change at 200 km.

I've also heard (and read in the owners manual) to try and avoid highway driving where the RPM is constant.

Does this sound sane?

Cheers

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Re: Fresh engine break in procedure?

Postby Dweezle » Fri Mar 23, 2012 11:50 am

That Is almost exactly the procedure we followed on the B6 rebuild.
All seems good.
No oil consumption and faultless for 20000 k so far.

Though we did about 50k on the first run.
Just to make sure all assembly lube was cleared.
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Fresh engine break in procedure?

Postby marty085 » Fri Mar 23, 2012 12:09 pm

Wait.. 20km? As in twenty kilometres? Sheesh should I be doing that? My mechanic said 1000km for first oil change which I thought was too long tbh and had intended to do it much earlier. But hadn't thought it would be as soon as 20. Im only 5km off that and I have been driving gingerly, not past 4k rpm so far... Am I going too easy on it?

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Re: Fresh engine break in procedure?

Postby manga_blue » Fri Mar 23, 2012 12:18 pm

SAb, your first post is virtually the opposite of what I was always taught about breaking in new rings. With an N/A engine the main idea is to give them a few long pulls of moderate to high compression to seat them. What I've done is to drive it gently out to an area with some long hills and then accelerate up them at abut 1/2 throttle in 4th from about 2500 to 5000rpm. About 5 of those pulls is all it takes to seat them. It's usually best to keep the rpm under 5000 until you've covered another 300km after that.

Are you using a break-in oil? Synthetic oils are not good for new rings, there's a high risk of glazing instead of seating. Castrol RX dino diesel oil is a good one for break in. Don't race on it though and throw it out after 1,000km.

Try googling "engine break in procedure".
Last edited by manga_blue on Fri Mar 23, 2012 12:24 pm, edited 1 time in total.
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timk
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Re: Fresh engine break in procedure?

Postby timk » Fri Mar 23, 2012 12:23 pm

manga_blue wrote:Try googling "engine break in procedure".


Only problem with this is every man and his dog has a different opinion, and it seems like people are just repeating stuff they have heard without having any first hand experience. :?

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Re: Fresh engine break in procedure?

Postby manga_blue » Fri Mar 23, 2012 12:28 pm

OK Sab, let me try this another way. The procedure I gave you is what I used for my last break in on the MX5. I did the 5 long pulls and then another 600km. After that I changed to synthetic oil and put it straight onto the Sandown track and set a personal best. That was 3 years ago and it has since done about 30 track days and 25,000kms and I still have not lost any compression.

This article, http://www.ntnoa.org/enginebreakin.htm , gives a reasonably good technical explanation of why you do it this way.
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Re: Fresh engine break in procedure?

Postby marty085 » Fri Mar 23, 2012 12:58 pm

Thanks for the info and link Manga :D

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Re: Fresh engine break in procedure?

Postby NitroDann » Fri Mar 23, 2012 12:59 pm

I agree strongly with magna blue.

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Fresh engine break in procedure?

Postby vrmmmpshhh » Fri Mar 23, 2012 1:57 pm

Best engine break in is to take it to a race track.

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Re: Fresh engine break in procedure?

Postby Sailor » Fri Mar 23, 2012 2:03 pm

Just drive it sensibly for ~1000km then oil/filter change.
If it's been filled with one of the 'running in' oils than get it out of there asap and put in some quality dino multigrade.
Keep the revs down to reasonable for the first couple of hundred kays, use the gearbox a lot don't let engine drop too far off its power band.
Don't do a trip to Melb from Sydney for the first 500kms unless you intend to go via the coast then the Snowy and Murray Valley Highways or similar.
Give it an occasional blurt to ~6000 rpm after that, by 1000km you should be seeing the redline now and then.

DON'T run it rich!!

Use Dino oil till the next oil change at ~5000km then switch to synth if that's your usual drop

We no longer live in the 50s/60s with mono grade oils which is where most of the conservative running in procedures came from
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Re: Fresh engine break in procedure?

Postby NitroDann » Fri Mar 23, 2012 3:05 pm

You HAVE to load it to generate combustion chamber pressure and speead the rings against the bore. Overrun vacuum pulls oil up the bores and cools/lubes them after the pull.

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speed wrote:If I was to do it again, I wouldn't even consider the supercharger.

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Re: Fresh engine break in procedure?

Postby toppertee » Fri Mar 23, 2012 4:00 pm

I use the bathtub curve theory.

Cheap oil for 200km, keep the revs up. Change the oil drop the clutch, then drive it like you stole it. Simple. (I.M.O.)
A well built motor is not going to fail because of poor breaking in.
(PM) Preventive maintenance i.e. schedule of planned maintenance going to be more of an issues in longevity of the motor.
Plus the motor needs to be built for the correct application.

Just my 2 cents. Good luck with it. :beer:

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Re: Fresh engine break in procedure?

Postby NitroDann » Fri Mar 23, 2012 5:31 pm

It has nothing to do with preventing failure, rather everything to do with lapping the bearings and rings in, so to speak. To ensure stront compression and minimize blowby.

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speed wrote:If I was to do it again, I wouldn't even consider the supercharger.

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Re: Fresh engine break in procedure?

Postby zero00 » Fri Mar 23, 2012 6:58 pm

saboteur

For what it's worth i've just been running in my NA6 after a complete rebuild from top to bottom

A few points they told me for first 1000km:

No long running at idle
up thru the gears is fine to around 4000rpm
No sudden deceleration
Do NOT run at a constant speed, vary it around as much as possible
City driving given the revs variation is fine
Don't let the engine 'labour' [Labor? where have I heard that recently around the State?]

After the first service, next 1000km or so up to 6000rpm thru the gears

Now done 4000km and OK to take it out to 7000rpm thru the gears, not easy to find roads you can do that on!!

I was also told to expect some use of engine oil at first while everything 'beds' in

Not sure if the same people who did mine have also done yours, I'm happy!!
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Re: Fresh engine break in procedure?

Postby marty085 » Fri Mar 23, 2012 8:12 pm

I have gone about 20km in three separate journeys and just realised I had the mechanic put in Synthetic Blend.. is my engine farked? :shock:

Or is not too late to put dino oil in tomorrow morning then try to bed in the rings and get some decent ring wear goin' on?

So pi55ed off. I had bought that oil when I was getting an engine swap, but then it became a rebuild and I thought it was dino oil.


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