In the next few days I will be faced with that nervous moment of turning the key for the first time on my rebuilt 1100.

Is there anything I should and shouldn't do when running-in the engine?

What are peoples thoughts on winding back the clock to zero, or is it better to stick with original kms?

I wouldn't bother winding the clock back.

Running in rules basically are.
Don't over rev. 3-4 thou is about the limit in the first 1000 kms.
Don't let it sit at the same revs too long.
Don't overload it at low revs (avoid that shudder).
Don't baby it too much. (a bit contradictory to the first bunch I know but that is what I've been told)
Personally I'd put some upper cylinder lube of some sort in with the fuel to make sure it all wears in in a slippery manner up top.
I've also heard it said not to run the engine in with friction modified oil. Apparently the rings wont bed properly with friction modified oils.

When I put in my first engine (rebuilt 1100) I was told several different things on how to run in an engine. Some people say you should just potter around in it and keep the revs low, some say drive it hard, but having had around 5 rebuilt engines in my car since then the easiest way to run it in is to simply drive it how you would normally drive it. Obviously dont rev the begeesus out of it or anything silly like that. I would say just take it kinda easy for 500kms or so, check the fluids regularly, bolt tightness, plugs etc. after that you should be fine to resume normal duties. I found my head bolts needed to retorqued after a few hundred kms but after the rest of the stuff that evil man did to that engine, that was the least of my worries

As for winding the clock back to zero, I did that when I first got my mini as I put in some different guages. Since then I've never wound it back again, but only because I like to know how far I've driven her. It's all personal prefference. I dont know what effect it has on resale as I never intend to sell my mini

basically what gibovski said but also look at some runnning in oil and change it to normal oil after 1000k's , avoid heavy braking , hard cornering and heavy acceleration (should be avoiding that anyway....)with this oil as it's thin and there's a chance it can surge forward away from the oil pickup in certain conditions (very highly unlikely but worth remembering considerring the cost of rebuilding a motor) . Don't thrash it but also don't granny it .

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Tim
The motor; It will be fairly tight (or it should be) and it could use a bit of oil at first. Take the spark plugs out and wind it on the starter until you know you have oil pressure. Only then try to start it. Let it idle for 10 or so minutes just giving the occasional blip to vary the revs. Watch very closely for engine and coolant temps and that the oil pressure is stable. It should be idling at about 50 lbs per sq in, but actual values do vary. Primarily it should be a stable pressure.

When you drive the car for the first time - look for smoke, listen for noises, smell for burning or leaking petrol etc - just be sure everything is in place. If your happy then put the car in fourth gear at about 40 kmh and floor it and let it pull to about 70 or 80 kmh. Repeat this for about three more times. This is putting full compression onto the pistons and rings making them bed in. Particularly watch the rear vision mirror for smoke in case the rings are not bedding.

If all is okay, then drive the car normally but gently and not labouring it for a couple of hundred km and then change the oil and the oil filter. You will feel as the motor begins to free up and you can begin to drive it a bit more enthusiastically but not big revs or clutch dumps.

By a thousand Km is should be fully run in and give you 50,000 or more km of good motoring.

I think the most important point here which has already been stated, is to pull the rotor button out or disable the ignition system. Remove the plugs. Wind the motor over until u know u have oil pressure!!! It actually took a few bursts of about 20sec wind overs b4 i got oil pressure.

Was the oil pump primed with vasoline? But yeah, sort ur idle and mixture out once its started but let it sit and idle for extended periods. Blip the throttle. Then just drive it.

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http://www.youtube.com/user/Hanras

Thanks for all the info guys.

Somebody told me to prime the oil pump by unscrewing the delivery line and pouring oil down there. Yes?

Yes - you can do it that way or you can unscrew the oil pressure relief valve - remove the nut, the spring and the cup and prime the oil pump from there - put it all back together and then wind it on the starter to pump up pressure.

We all assume you were very generous with the assembly lube as the motor went back together. The motor only needs to be running for 20 seconds or so without oil pressure (specifically a supply of lubricating oil) for a bearing to grab or something similar and the lot goes down the drain.

you want the rings to be bedded in properly so you want the engine to go through the whole rev rang (dont flog the guts off it as well as dont drive it like a grandpa) just ease it through the gear changes and once in 2nd and 3rd, bring it up to 5-6k smoothly

but yeah listen to whats been said, make sure you have oil pressure and look out for leaks and strange noises

gluck, post some pics up or even a vid if you can

If its a new cam, once u get it running, run it up to 2000 RPM for 20mins, to bed in the cam, wen you turn it off, thats wen she smells hot, and u know that the rod bolts wer put in correctly, and that your engine builder DID remember to install the gudgeon clips

Goodluck mate, I too am abou tto hit the key on a new mota, its always an interesting time!

-Cam

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IS NOW BACK ONLINE AFTER SOMETIME..... SORRY TO ALL, FOR NOT REPLYING TO PM'S!!

No need to mess with the relief valve. Half what you pour in there will probably drain into the sump via the valve's relief port.
The banjo pipe fitting also leads down to the oil pump, and is more vertical so the oil will stay there- so use that. After it's poured in to the top, turn the motor backwards a turn or 2 by pushing car backwards in 4th gear.
I then screw the banjo bolt in but leave it a turn loose- so if the pump has any air it avoids an air lock. Crank the engine with plugs out. When you see oil oozing around the bolt head, then tighten it up.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

I agree with what the Doc says about priming the oil pump. That is the best way.
Illegal and silly.

There have been a few threads on this over the years, I recommend a search.

I think in one I posted a link to a bike mechanic that talked about how much of a power difference the running in phase could make to the final engine. He had evidence of otherwise identical stock bikes making considerable different HP because of how they were run in.

He advocated running in by creating large combustion chamber pressures to ensure the rings bed in. i.e. put the engine under load at full power.

The was some conjecture here about whether these techniques would apply to a 60y.o. engine design, but I think someone pointed out that modern rings would all be constructed the same way.

http://mototuneusa.com/break_in_secrets.htm

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"Life is not like a box of chocolates... it's more like a jar of jalapenos. Whatever you do today, may burn your arse tomorrow."

Thanks again for all your comments.

Morris1100,
I didn't consider the legality side of winding the clock back to zero.
It'd probably cause problems at the rego branch too.

I thought I'd bring this old chestnut back to life.
Here are some thoughts from the US on running in new engines, food for thought.
Graham Russell does a very fine hone pattern on his rebores, I think this link pretty well agrees with his dyno run-in method.
Comments??
http://www.mototuneusa.com/break_in_secrets.htm

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.