Running in a new rebuilt engine

My rebuilt engine has gone back in the Uno this week,

The bottom end was balanced , honed etc, head skimmed and valves done plus a new piper fast road cam, T25 etc hopefully should go even better.

Any tips of running it in?

There's a different view on it here!

http://mototuneusa.com/break_in_secrets.htm

I personally wouldn't run it in like that.

As you have a new cam you need to make sure you apply oil/lube directly onto the cam within a couple of hours of starting (ideally just before). Start with minimum application of throttle and let fast idle (2000rpm) for 5mins (keeping an eye on oil pressure) to bed in cam then turn off.

Check oil level and top up if required.

Assuming everything is as it should be (no leaks etc) start engine and run at a range of speeds up to 3000rpm (steady with the throttle) to warm up and check coolant system integrity.

If confident everything is OK then take the car for a 1/2hour drive but stay local. drive at 1/2 throttle with low load and low speed.

Break-in: Drive for one hour at max 1/2 throttle going through the gears. During this time NEVER use 'high-gear - low engine speed' as this will lead heavy bearing load during low oil pump flow.

After the first hour of driving as specified above continue the break-in phase at 3/4 throttle. Drive at a range of speeds for the next 200 miles to fully bed in. I would then change the oil and filter and drive it normally.

This is just my take on it from reading and personal experience and can not be held responsible for any loss or damage caused from following my method.

Liam

I

Very controversial topic bedding in an engine and no one even seems to do it the same way.

My personal route is similar to that mototune link    ,although you also have the cam bed in to think about aswell.

I have never bedded in both at the same time and when I did mine I did not bed in the cam,i think after 5k later a couple of the lobes were showing some bad wear.
How much of this was because of not bedding it in I don't know,but i also think using a used cam and used shims proberly contributed to it.

On some cars I don't think the cam bed in is quite as important but due to the unos bucket design it is more likely to be a problem I think.
I have also seen this in punto gt's aswell with wearing cam lobes so its definatally worth keeping in mind when bedding the engine in.

I also always use millers bedding in oil when running the engine in.

http://www.millersoils.co.uk/automotive/tds-automotive.asp?prodsegmentID=187&sector=Motorsport

If this contributed to the cam wear I don't know but I would not of though it should of being a bed in oil, but you never know with all the talk with flat tappet shims and later oils that don't contain as much zddp additive which could cause accelerated wear.

I think the cam and piston rings almost want different things,the cam as much lube as possible to stop galling where as the rings not so much so it gets a better chance to bed in well.

Tbh I would still be wanting to use a bed in oil or maybe a mineral equivalent as I don't think synthetic is the way to go for a good bed in for the rings.
I would obviosly check that the millers would be ok for the cam but if I was to do it again I would stick with that.

Worth remembering though is that the millers bed in oil is only good for up to 500 odd miles and you also need to make sure you don't exceed the operating temp of the oil.
You should also be checking your air fuel ratios really as if you run it to rich on this oil I think your chances of bore washing it will be a lot higher than when running on a good quality synthetic.

Anyhow heres how I would do it,although I will proberly forget something lol

Millers oil and decent amount of proper cam lube.

Prime oil pump a few times with old timing belt and spare oil pump gear/cam gear on drill with rocker cover off to check oil is making it to the cam.

Then remove spark plugs and possibly disable fuel pump and crank over to get oil pressure light to go out.

Maybe cover oil cooler depending on out side temps and cars normal operating temps.

Start up and get revs above 2k straight away and keep blipping/holding the throttle at different rpm now and then between 2-3k, never letting it drop below 2k and do this for 10mins minimum to 20mins max I would of thought.
Another tough call this one as you want to get on to bedding the rings in as soon as possible imo.

In this time topping up water and checking for problems.

Switch off one last check then off up the road,hopefully the oil and water temps should be good by now and if not I would drive semi off boost until I had around 80c oil temps .
Even if the temps aint quite that high I would personally still proberly start getting on it sooner rather than later but that's a judement call at the time,i would not be babying it about for ages waiting for the temps to come up,this is why it might be worth covering the oil cooler if you struggle to get the oil temp up.

So straight of I would be bringing it on boost(actuator pressure or around 1bar max) from 2nd to 4th,not full throttle yet but a decent half throttle to around 4k-4.5ish on the mk1 (3k full boost),I would not be loading the engine to hard from low down just a steady part throttle 2-4 through the gears on boost for around 1000-1500rpm rpm a few times.
But straight after each pull I deaccelerate with no throttle for as long as I have just accelerated for,there was a reason for this but I be fucked if I can remember what it was   ,possibly to draw the heat away from the rings or something.

Anyhow I would continue like this slowing increasing and varying the loads with an occasional break inbetween, I would still never cruise it for long though and always still be looking to varying the revs/loads and doing short pulls on boost.

It don't have to be 2-4 just what you can do,might be just be a quick 3rd pull into boost and then deceleration depending on traffic or space,but I am always aiming to lightly load it through the gears on boost when I can, varying how hard and long I load the engine for and from how low down and how high I rev it.
I always start of slow but by 20mile I would most likely be using full throttle by now for short periods and reving abit higher.

All this time keeping a very close eye on oil temps and possibly even stopping and having a quick check up after 20 odd miles.
An oil/filter change for more running in oil could be done now for extra peace of mind but I normally wait until later but between 20-100miles is normally the norm.

After around 20-30mile I would almost be driving the car as normal in terms of full throttle and  loads etc and would be doing longer/harder pulls but still with the same equal deacceleration, and proberly be reving upto 6k+ now and then by now.
Nothing crazy just using more of the rev range and higher loads and full throttle for longer periods.

50-60mile I would proberly be using all revs full throttle now more often but still not going mental and still just basicly be driving varying the loads though the gears with the same deacceleration inbetween.


75-100mile I would be swapping the oil/filter for more running in oil and then just driving as normal, but with in the limits of the oil,ie no top speed bashes or super high oil temps.
I would still not be wanting to cruise at set revs for miles in it just yet but would consider the most part of the bedding in to be done by now and can be driven normally.
I would have no problems at driving it at 100% now for short periods,its more the protection of the oil that would play on my mind until I would want to thrash it for longer.


I would stay on the running in oil for another 2-3 250-350mile changes up to 750-1000 mile then I would run on synthetic oil.
More for the peace of mind really and the benefit of flushing the oil,but in reality I proberly think its proberly mostly bedded in by 500miles.

I am also going to copy and paste Liams disclaimer into my post as it seems a wise idea,especially as my way may seem a little harsh   

This is just my take on it from reading and personal experience and can not be held responsible for any loss or damage caused from following my method.

Ok thanks some good tips there, i've ordered some of that bedding in oil and millers cam lube.

Good idea re oil pump, thats the next job now as have just finished installing all the sensors and pipes etc

Its a 2nd hand Piper cam, but in good nick and 2nd hand shims except for one new that i needed to order in.

No worries re disclaimers! if something goes wrong it will be down to me, its a bit of a learning curve, i've also got the T25 going in i've rebuilt myself.  

If it all goes to plan, i'll look at getting it on a rolling road and proper set up as the mixture etc may not be quite right now with the additional mods.

I think its all the same on the mk2 but I would suggest maybe flipping the used shims to the new/unworn side if you have not done so already.

There are varying opinions to doing this,but after eating a cam I would always want to bed a new/different cam in with new shim faces and not worn ones.

I flipped a few of mine and its been fine so far and I have checked the cam a few times aswell lol
It is mentioned in the gc book on p63 "fit new shims or invert old ones if unworn on one side" so I just went with that lol.

Ah ok, will do that then

Aren't they a sort of matt finish on the side with the number etched into them?

I just make sure oil and water is getting where its supposed to go, get it up to temp and then knock the living daylights out of it until I find something broken.

But the above method is no doubt a lot safer   

Mine have always looked pretty much the same both sides,especially when new.

I think the genuine fiat shims would of proberly looked similar when new its just where there worn and shinny now?

Its maybe worth looking into it then as I obviously don't want it being wrong, but there are quite a few flat tappet shim and worn cam storys out there on various older cars.
Its proberly not ideal but I think considered better that than running on used shims/different cam,some would say always use new.

I am not saying you will not get away with using old shims as I am sure many have,but I think it just increses you chances of it going tits up lol
Maybe I am just paranoid lol but I am just trying to give you the options to research that I totally neglected the first time around and ate my cam   

Bloody shims!

Just done a search and pretty sure the other side of the shim is the ground side and is quite rough

from fiatforum - Depends on machine shop but dont use the ground face against the cam it will wear the cam lobe very quickly!

from Guy crofts website = refer to GC ‘How to’ data. You must always use NEW shims when changing cams.

Looks like new shims then!

Haha yeah it is a nightmare trying to find wrong from right,but if you can it is definatally best to use new shims.

I was quoting gc's early build book just for reference so maybe he has changed his ways.

Its also worth bearing in mind that not all aftermarket shims are of the same quality either lol

All good chat mate

Get mine from DG rally, they look genuine

I've just taken delivery of several brand new shims & they're the same finish both sides, not particularly smooth/shiny?!

richvans wrote:My rebuilt engine has gone back in the Uno this week,

The bottom end was balanced , honed etc, head skimmed and valves done plus a new piper fast road cam, T25 etc hopefully should go even better.

Any tips of running it in?

There's a different view on it here!

http://mototuneusa.com/break_in_secrets.htm

I certainly wouldn't agree with running a rebuilt engine in like that, even more so an older design as per the Uno Turbo. For instance, modern engines are built to much higher tolerances, plus many are designed to run on synthetic oil from new. As such they need less running in than older engines, so what applies to them does NOT apply to older engines built to lower tolerances.

The golden rule when running in a rebuilt engine is to increase the power, revs and load gradually over time, and to never, ever load the engine i.e. let it labour at low revs or thrash it at high revs, until the engine is fully run in. Better to let it rev in a lower gear than labour under a higher gear, though avoid high revs at least for the first 500 - 1000 miles. Also, under no circumstances let the engine get too hot/ over heat as that is a killer for new parts bedding in. I would also use a good quality mineral or semi-synthetic oil for the first 1000 miles (fully synthetic might not allow the parts to bed in fully during running in), and I would change the oil (and filter) at 500 miles and then again at 1000.  Changing oil is far cheaper than rebuilding engines.

Other people may advise differently regarding running in a rebuilt engine. What I mentioned above has been mostly the standard for decades, and generally has proven to work well. It's your choice as to how you run yours in, so it's up to you to take the available techniques and choose which one you feel is best for your engine.

Cheers yeah i'll go for the sensible run in!

Just filled up with bedding in oil and did the drill / old belt on the pump gear and that worked a treat, got oil coming through the cam oil galleries and through the turbo   but also noticed a little leak on the oil filter mount to block, so that will have to come off again!

Its running ! sounds real nice, just need to fit the newer bumper and front wheels before the weekend

Insurance / tax sorted for Saturday ready for road run in  

Had a few teething problems, the main one being the T25 i rebuilt ... Oil in the exhaust chamber so initial start up was smokey    so that had to come off, mani etc all off again!, its now got a hybrid standard turbo, which i've not used before so fingers crossed that's not goosed aswell otherwise it back to the standard turbo which was fine. 2nd startup 2000-3000 tickly tickover was smoke free, so looking good

All good so far! Up to 30 miles now, had a few little leaks and a bump start from some lads after stopping to check everything but the battery hadn't charged enough!

The plastic expansion tank had a split and my spare had a split in exactly the same place! so its now got a ally Forge one fitted and its taken 3 swaps of the oil pressure sender to get a decent one fully working, lots of pressure so thats looking much better than the last engine.

Still taking it pretty easy just, lots of accelerating and decelerating round country lanes and no loading or too high revs, it really wants to though! lol