Engine break-in

Just wondering what the best way is to break in a newly re-built engine. only about 160kms on it so for , havent gone above 3500 rpm, very light throttle, bsacially driving it like a granny, and will gradually go up in the revs every 100kms or so

Lots of different opinions on the matter on the interweb, just wondering what folks on here would do.

I know roller work would be expensive but I heard it's the best method.. maintaining constant revs etc suppose Nick would be the man to answer that

first 250 miles rev to 3.5 and do an oil change/filter, then another 250 miles at 4.5 oil.filter again then 500 miles rev 5.5 oil/filter again mineral oil is fine for run in, no motorway miles the engine needs to be under load especially the first 500 miles high gear up hills is what i done as thats how i was told to do it,they say the first 250 miles is the crucial area and if you dont spin a bearing ect the engine should be fine as it most likely to happen with in the first 250 the more miles you get up on it the better i done nearly 2000 miles before mapping and change oil and filter just before you map and use what ever oil you engine builder suggests

thats a lot of oil! especially when your using the Motul 300v! so i might go for a spin up the mountains tonight, i drive on the m50 every day though, maybe ill take the back roads for next few days!

any cheap mineral oil will do 20/30 euro job the use ur motul just before you map and from then on in....you need to do as many oil ans filter changes as you can before you map it will be the life of your engine

righteo i might change to castrol magnetec so for oil change at 500kms and back to motul once run in is done.

your nxt oil change should be at 250 miles

Animal Spec c's info is 100%.

I broke my engine in up the dublin mountains, loads of gear changed ,vary the revs and loads on the engine, if your using mineral dont boost her. Mine has 20k kms on it now , still going strong.Thats what I would do Dan

You could be after missing the train already Dan, first 20-30 miles is where you bed in your rings, if not then you can glaze over the hone, and you could end up with an oil user of a car. Cheap mineral oil is what you use for this, after that you switch back to a normal oil, mineral oil wont protect the bearings, but will allow rings to bed in, after 20 to 30 miles of a small bit of boost up and down through gears, the rings will have wore in so no need for the mineral oil anymore..

You also need a little bit of boost, this is needed to push the rings out tight to bores, a bit of brisk country road driving, with plenty of on off throttle, and engine braking

Doddling around is not a good break in procedure, you need a little bit of wear to occur to rings.

Its said that a very light hone was done on the 2.5s in factory and this is why they were oil users as rings didnt bed in.

[quote author=Altezza-Dan link=topic=33438.msg383151#msg383151 date=1330362242]
Just wondering what the best way is to break in a newly re-built engine. only about 160kms on it so for , havent gone above 3500 rpm, very light throttle, bsacially driving it like a granny, and will gradually go up in the revs every 100kms or so

Lots of different opinions on the matter on the interweb, just wondering what folks on here would do.
[/quote]

Did you build it yourself? If not what did the builder say?

The lads are correct in what they said, motul is too good to use for running in.

Did the builder give you a run-in procedure to follow? If he didn't then he should have, and if he did, you should be following that if you are going to have any chance of a comeback if something goes wrong.

A mate of mine was told to bed in exactly as was said above. I can't remember the exact mileage for changing the oil but I know the engine builder put in a very light oil to begin with and he was told to drain that out when he returned home (approx 75km) then to change to a decent quality but cheap oil until the 800km mark. I'm pretty sure he had 4 oil changes done along the way by that stage and was also told to avoid motorways completely.

Martin Tracey said to me when I was bedding in mine,just put in whatever oil your going to use through out the life of the engine from the start. I still put mineral oil in though when I was doing it.

Cheaper mineral oil is used because it will cause higher temps and more friction which helps to bed things. Good oil like motul etc is just too good so things don't bed in properly and then you end up with problems down the line.

Ken and Alan would know a hell of a lot more about building an engine than i would but thats the gist of it.

[quote author=KENC link=topic=33438.msg383174#msg383174 date=1330369770]
You could be after missing the train already Dan, first 20-30 miles is where you bed in your rings, if not then you can glaze over the hone, and you could end up with an oil user of a car. Cheap mineral oil is what you use for this, after that you switch back to a normal oil, mineral oil wont protect the bearings, but will allow rings to bed in, after 20 to 30 miles of a small bit of boost up and down through gears, the rings will have wore in so no need for the mineral oil anymore..

You also need a little bit of boost, this is needed to push the rings out tight to bores, a bit of brisk country road driving, with plenty of on off throttle, and engine braking

Doddling around is not a good break in procedure, you need a little bit of wear to occur to rings.

Its said that a very light hone was done on the 2.5s in factory and this is why they were oil users as rings didnt bed in.
[/quote]
there was already about 20-30 kms on the car when i picked it up, so the initial bedding is was already done. was told to gradually build up to higher revs with short bursts at higher revs, low revs buy high load, went to go up the mountains for a spin tonight after work, i got as far as turn past viewpoint and fog was so thick i could not see 10 yards on front of me had to turn around! i realised i never reconnected my fog lights when i had the bumper off.

So run in procedure what AL said is pretty much the same as want im doing and what i was told to do so all is good.

Apart from the oil

i used what was suggested to use so im happy out with that.

I agree with Ken here.

First 10-20 minutes of engine life after rebuild are the most important. Never run it in on idle. Give it some trashing without boost... its all about short peaks of keeping it under load.

I've noticed more and more professionals recommend this rather controversial method http://mototuneusa.com/break_in_secrets.htm

Including Andy Forrest

Plus running in - mineral oil should always be used at the very beginning of running in procedure. -
The reason the bores are honed with cross hatches is so it is so the bore is abrasive for a short amount of running in time to wear the rings down to seal perfectly or as perfect as possible. Top quality fully synthetic oil is too slippery (its too good of a lubricant) for the cross hatches to wear down the rings properly.