Run in Gentle miles

[DerekR]

I pick up my new ES diesel 2.2 in a couple of weeks and intend to work it reasonably hard from the start. I know that tractor engines are different (more torque and a lot less revs) but a local agricultural contractor who buys several new tractors a year, swears that the best tractors are always the ones worked hardest from the start.

[Pottsy]

I used to build racing engines (NA, petrol), although this was a while ago. I do have a degree in Mechanical Engineering, but to be frank it is not as much help as some of the specialist text books I have on the matter (as well as learning by my numerous mistakes and occasional successes!)

Here is a excerpt written in 1981 from the leading author of race engine building, about running in conventional petrol racing engines. I hope it helps balance the entry in the wiki and the mototune site. In fact, I'll pop it into the wiki now.

The initial bed in of rings is achieved by giving the car a full throttle burst for a few seconds, followed by snapping the throttle shut and coasting for a few more seconds. This should be repeated at least twelve to fifteen times with the engine at normal operating temperature. Accelerate the vehicle in top gear from the slowest speed it will pull in that gear.

By giving the engine full power, the high gas pressures force the rings out against the bore wall. Snapping the throttle shut causes a vacuum in the cylinder which draws up extra oil. This and low engine speed minimises the risk of glazing and allows the ring face and cylinder wall to cool.

After the rings are initially bed-in, the engine can be operated at up to 80% of its rev/power potential, but constantly vary the speed. If this is not done, the rings may still glaze. After about half an hour of this on the dyno or the race circuit, the rings can be considered as being run-in. A road engine with chrome rings should be run in for around 200 miles, preferably in one session. Again, constantly vary the engine speed and include heavy acceleration for short bursts as for initial bedding in. Avoid constant high speed until the engine has done 500 - 700 miles.

I prefer to break in my engines on the dyno, carefully controlling the engine speed and load to ensure long engine life and maximum power. This takes 2-3 hours for most brands of engines. When the engine cools, the tappets are adjusted and the head is retensioned. Then, following a warm-up to bring the water and oil up to temperature,, full load power tests are made to determine ignition advance, fuel jet sizes etc. By the end of the tests the engine is fully run-in, having spent at least four hours running on the dyno.

[Cap]

Originally Posted by DerekR

I pick up my new ES diesel 2.2 in a couple of weeks and intend to work it reasonably hard from the start. I know that tractor engines are different (more torque and a lot less revs) but a local agricultural contractor who buys several new tractors a year, swears that the best tractors are always the ones worked hardest from the start.

Id rather listen to real experience (years of practice) and follow your way (the hard way) rather then theoretical ********

In Norway we have an expression called "daukjørt" wich means a car that is really slow and no-responsive... This term usually applies to a car driven by old people, and the reason? Yes, because they never flor the pedal or go above 2500 revs

[Bog]

Originally Posted by Cap

In Norway we have an expression called "daukjørt" wich means a car that is really slow and no-responsive... This term usually applies to a car driven by old people, and the reason? Yes, because they never flor the pedal or go above 2500 revs

Also know as the 'John Lickman' method

When I first got my 1.8, I drove it hard (not thrashed) and it is now very quick and responsive, with great mpg. I've not had to top up the oil either.

As to wether it would be any different if I had driven the first few miles gently, who knows and who cares! I'm more than happy with the performance of my Civic.

[PJS]

Interesting exerpt there Pottsy, but I wonder how relevant 26 years later.
Back then, tolerances were nothing like what was used, and I imagine the piston ring material has changed too.
Up until probably 8-10 years ago, I'd say piston-slap was a valid term - not nowadays, or at least not to the extent it was referring to, back then.

[Cap]

Originally Posted by Pottsy

Brodders - have a peek at the Myths section of the running in article. I got this confirmed by an employee working in the engine assembly plant.

So this means the motor is fresh from factory i.e not run in or tested? Maybe just started once?

[Pottsy]

Originally Posted by PJS

Interesting exerpt there Pottsy, but I wonder how relevant 26 years later.
Back then, tolerances were nothing like what was used, and I imagine the piston ring material has changed too.
Up until probably 8-10 years ago, I'd say piston-slap was a valid term - not nowadays, or at least not to the extent it was referring to, back then.

Not so - the ring materials quoted in the book for racing engines are the same as current production ones, and the tolerances on a racing engine are likewise the same as production.

The important issue is how to effectively fit the rings into the honed bore. My experience, engineering practice, the text from that book and the mototune site all say basically the same thing. The rings need seating into the prepared bore by using bursts of power, and that varying the speed and load of the engine for the first few hundred miles is very important. Driving gently will glaze.

Originally Posted by Cap

So this means the motor is fresh from factory i.e not run in or tested? Maybe just started once?

Yes. But probably run a few times - moving around the factory, transport, dealer PDI/road test and so on.

[Greedy]

Ok Factory fact from someone who was there for 14 years.

Engines are not 'run in' at the plant. Infact most enignes have not even been started until the car is started 1st time at the end of the line - ie only samples are run on the engine line (cos the engines are so dam good they are always right first time).

Having said that all cars go up and down the test track at leats once. It's the old Vickers runway so it's couple of mile round trip. The car will reach about 60/70 and not with a light foot approach but are not ragged, just put through their paces - hair pin at the bottom, accel up hill on the way back and the ' slalom and cobbles' to check for any problems.

Therefore your car has done a couple of miles up to temperature and under load when you get it.

I've had double fiqures of Honda's in my time and have never 'run in' one gently but always have stayed away from the limit for the first few hundred. I have NEVER had a problem. And when there are a couple hunderd 1.4 Civic's all racing down the A419 end of shift then those extra 1 or 2 bhp show and I was never last.

As for brakes. Wearing them in is not the problem, as Honda's disc finish is second to none. The problem is Temperature. Don't go standing on them and getting them hot straight away. They should be cycled by gettting them warm and letting them cool a dozen or so times getting them slightly hotter each time. It's the bringing them up to Temp (and coolign them down) progressively that gives them the longevity.

So that's how I do it and remember - An opinon may not be right but it is never wrong because it's an opinion not a fact.

[Cap]

Thanks Greedy for sharing good info!

[Pottsy]

Originally Posted by PJS

Interesting exerpt there Pottsy, but I wonder how relevant 26 years later.
Back then, tolerances were nothing like what was used, and I imagine the piston ring material has changed too.

Now I have had a moment.. Let's compare the tolerances quoted by this 1981 text for use when putting together a club racing engine, compared to the manufacturers of today:

Ring - groove gap (thou):

Then: 1.0 to 1.5. Absolute max 2. Road car absolute max 3.5
Civic 1.8: 1.8 to 2.8 new. Service limit 5.

Materials are all still the same - moly / chrome / iron.

Honing technology has improved, but this will just shorten the ring run-in on the modern engine.

I suspect people still think running in now is in some way related to running in an engine of the 1930's - when you actually had metal to metal contact that needed wearing away. This hasn't been the case (with the exception of piston rings) for a long time now!

[amronno]

Originally Posted by Pottsy

I think what he meant to say was that there's no real need for a special running in procedure...

Yeah, that's exactly what my dealer told me, just avoid hard accelerating and preferably keep the rev below 3500 r/min. Apart from these two exeptions there are no obstructions, not even for motorwaydriving! The engine works with very low strain anyway, IMO!


Oh, and one more thing, nearly forgot, of course avoid heavy braking....that's important to keep in mind!

[GHGH]

For the first 1000 km / 600 miles, I drove the car gently with variable load (inevitable in hilly Trondheim). Quite a few acceleration bursts, but never over rev.

Think that was OK, after a oil top up after 1500 km the engine uses no oil at all. It feels also very flexible at low revs and potent at high revs (but how is I to tell after trying only one civic?).
Petrol use at extra urban cruising 5.8 - 5.9 l/100 km (48 MPG), increasing to slightly over 6 on bad roads and/or inspired driving.

[Cap]

Sounds good mate

When did you do your first oil-change GHG or not done yet, just topup?

[GHGH]

Yes it does - ecpecially over 4500 o/min!!!
3dr gear is a gem when overtaking at "norwegian conditions" - max torque from just above 80 km/t (62 mph) - lasting to over 130 km/t (80 mph)!

[GHGH]

Originally Posted by Cap

When did you do your first oil-change GHG or not done yet, just topup?

Sorry I did'nt see this in my last answer - still early morning in my head.

I've had one top-up after 1500-2000 km (900 -1200 mi), an thats all!
Have checked at least ten times - almost no oil use at all.
Planning to change oil at first service (20000km/ 12500mi), as prescribed.
For me it probably will be once a year.
Some say that oil chang should be more frequent than that.
Any opinions on that anyone?

[Cap]

Originally Posted by GHGH

Sorry I did'nt see this in my last answer - still early morning in my head.

I've had one top-up after 1500-2000 km (900 -1200 mi), an thats all!
Have checked at least ten times - almost no oil use at all.
Planning to change oil at first service (20000km/ 12500mi), as prescribed.
For me it probably will be once a year.
Some say that oil chang should be more frequent than that.
Any opinions on that anyone?

If you check this post Running in

and the link to mottotuneusa, they say its important to have an early oilchange after the initial bedin (300km/200mi) to get rid of impurities (metal and other objects) but i guess you can do it later.. But im planning to do a first oil/filter change atleast before the first 1000km and then again at normal service intervalls like 20000 to be absolutely sure...

[GHGH]

Just in case the oil filter dont clean it off?
Well it's too late for me anyway - approaching 14000km /900mi.

[Cap]

Originally Posted by GHGH

Just in case the oil filter dont clean it off?
Well it's too late for me anyway - approaching 14000km /900mi.

I guess so... But anyway its no danger, just for the really picky people i guess.. As the dealer recomends at 20000 then no problem.

[nortones2]

My impression is that making the diesel engine work hard, but being aware that it needs to be warmed up and warmed down, gets the best out of it. However, the phrase "Snapping the throttle shut causes a vacuum in the cylinder which draws up extra oil." must be relevant to petrol engines with a throttle (not all have them now - e.g. BMW) but not to a diesel where there is no throttle, and no vacuum can be created

[transmitdisrupt]

right so i pick my 1.8 type s gt up next week, so you guys based on experience think that to get the best results, i should warm the engine first, then boot it up to about 3500rpm, then foot off the gas for the first 200 miles? and stay away from the redline until 5-700ish? just to confirm?? This is my first new car, so ive never ran anything in before...

cheers guys