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Discussion Starter #1
Hi all, I'll be finished with my 2.0 V6 TB rebuild project soon so I was reading about engine break in on internet and there are very different stories.

I wanna make sure I'm doing break in as manual says but that information for me is unavailable

I would like you guys to tell me your experience for your or your buddys break in results...:thumbs::thumbs:
 

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I'm sure the two very different stories you have read are:
1) Thrash it from new
2) Run it in as it is stated in you cars handbook (low rpm and small throttle openings for the first 600 miles and gradually increase them)

I rebuilt my bike engine and thrashed it after 20 miles (I wanted to make sure it wasn't overheating/ leaking fluids) and it has produced a very healthy dyno result. Personally I think the second option is there to make sure that the you have time to find any loose parts on the engine before you use it in anger.
 
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Drive it like your last day on earth!!
If it lasts the day, do it again till it breaks!!!
Chances are it won't break and you'll have a very quick motor!!!

Do it like the book says and you'll have a glazed up engine that will never breathe properly!!

This is purely based on my experience of older cars before fuel injection became common, the new ones I had were pushed hard from day one and never let me down!!! Even my diseaselled Alfa!!
 

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Discussion Starter #4
Also forget the "story"about oil, some recommend sae 30 non detergent motor oil others 15W-40 mineral???
 

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Discussion Starter #5
I'm sure the two very different stories you have read are:
1) Thrash it from new
2) Run it in as it is stated in you cars handbook (low rpm and small throttle openings for the first 600 miles and gradually increase them)

I rebuilt my bike engine and thrashed it after 20 miles (I wanted to make sure it wasn't overheating/ leaking fluids) and it has produced a very healthy dyno result. Personally I think the second option is there to make sure that the you have time to find any loose parts on the engine before you use it in anger.
not sure what means "trash it from new" since I'm from Bosnia...sorry
 

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Discussion Starter #7
as fast as I can, going red or? Thanks allot for advice
Also think that vay engine will be beast or will die, am I right?
 

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You are not supposed to push the revs into the red line often but it's ok to take it near it. I have heard that it "it will be a beast or die" but I think it needs to be done. I would wait for Alfa Tuner and DavidC's input before trying anything though, they know a lot about these engines.
 

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Personally I'd run the engine in by driving it normally ("normal" normal, not "lunatic" normal).

The things to avoid are using too much throttle at low revs .. too high gear .. or labouring the engine (such as going up steep hills, using low gear and big throttle).

Avoid anything where the engine is under load. The engine wants to run under a light load.. so imagine driving it down hill with just a small amount of throttle.. that's perfect for it. Speed and rpm doesn't matter like that.

You must vary the revs though. It's no good getting on the motorway and driving at 100kmh all day. You have to get onto some normal roads where you can use the engine 0 to 2000.. 3000... 4000 or 5000 rpm .. use your judgement.

You'll feel that the more miles you do the "looser" the engine will feel and you can use more revs as you feel like it. I don't see any point to go to the red-line for "running-in". If 5000 rpm doesn't do it, using the red-line won't!

For oil, use a semi-synthetic 10W40 "for diesel" engines.

Too-good oil (synthetic) will prevent the engine bedding in for a loooong time. 10W40 semi-synthetic will do the job. Using "for diesels" engine oil will help clear out any bits of loose gum, varnish and "stuff" that may be loose after the engine was apart - "for diesels" engine oil has more detergents in it.

Then... change it and the oil filter after 2000kms just to get it and any loose bits of rebuild out ..and replace it with your favourite oil.

It should be a good old donkey after all that.


Ralf S.
 

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You must vary the revs though. It's no good getting on the motorway and driving at 100kmh all day. You have to get onto some normal roads where you can use the engine 0 to 2000.. 3000... 4000 or 5000 rpm .. use your judgement.
+1 This is really probably the most important part. Vary the revs, don do a lot of highway driving at steady speed and don’t let the engine idle for a long periods of time.

For oil, use a semi-synthetic 10W40 "for diesel" engines.

Too-good oil (synthetic) will prevent the engine bedding in for a loooong time. 10W40 semi-synthetic will do the job. Using "for diesels" engine oil will help clear out any bits of loose gum, varnish and "stuff" that may be loose after the engine was apart - "for diesels" engine oil has more detergents in it.
With synthetic the engine will bed is as fast as with mineral, the reason is somewhere else. There is one big difference between mineral and synthetic. If you overheat synthetic oil, it deteriorates. If you overheat mineral, when it cools down it gets back its original properties. During the run in period there are components in the engine that are not yet smoothened by their movement, or are not seated properly, or the imperfections on their surfaces rub. On these surfaces the micro volumes of oil can really overheat to hundreds degrees. In case you have synthetic, this means that it will deteriorate faster.

However, the manufacturing tolerances and surface finishing is much better now and the parts are much more precise and don’t need to bed in as much as 30 years ago. The bedding in process doesn’t have so big effect as in the past and you can use synthetic from the start. However, for the peace of mind, I would recommend to change it sooner.

At the moment I am going to run in the rebuilt engine in my GTA. When the snow melts, I plant to do a lot of countryside driving over the weekends and to change the oil after 2000kms.
 

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+1 This is really probably the most important part. Vary the revs, don do a lot of highway driving at steady speed and don’t let the engine idle for a long periods of time.



With synthetic the engine will bed is as fast as with mineral, the reason is somewhere else. There is one big difference between mineral and synthetic. If you overheat synthetic oil, it deteriorates. If you overheat mineral, when it cools down it gets back its original properties. During the run in period there are components in the engine that are not yet smoothened by their movement, or are not seated properly, or the imperfections on their surfaces rub. On these surfaces the micro volumes of oil can really overheat to hundreds degrees. In case you have synthetic, this means that it will deteriorate faster.

However, the manufacturing tolerances and surface finishing is much better now and the parts are much more precise and don’t need to bed in as much as 30 years ago. The bedding in process doesn’t have so big effect as in the past and you can use synthetic from the start. However, for the peace of mind, I would recommend to change it sooner.

At the moment I am going to run in the rebuilt engine in my GTA. When the snow melts, I plant to do a lot of countryside driving over the weekends and to change the oil after 2000kms.
Both synthetic and mineral oils will detriorate when overheated, but mineral oils are worse as they deteriorate at lower temperatures.

Black sludge is caused by overheated oil.

Synthetic oils are designed to have even sized molecules, which results in better lubrication. Better lubrication results in running in taking longer, so a mineral is a better bet.
 

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Both synthetic and mineral oils will detriorate when overheated, but mineral oils are worse as they deteriorate at lower temperatures.

Black sludge is caused by overheated oil.

Synthetic oils are designed to have even sized molecules, which results in better lubrication. Better lubrication results in running in taking longer, so a mineral is a better bet.
from my experience of building engines ive used a cheap 20/50 oil for first 500 then dropped oil and new filter then put the good stuff in
in running in period i use full rev range but never have motor labouring and occasionally open her up but not flooring throttle to floor:thumbs:
 

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I would probably go down to Asda and buy their own brand 10w-40 mineral oil (Which is made by Tetrosyl)

It meets API specs, and well as the regular (not high performance) ACEA spec.

Most 20w-50 oils are not certified to either spec, and they are usually very poor quality.


I know he wasn't running in, but my dad put some cheapo 20w-50 in his Rover 216 (Honda engine variant) within 500 miles it was rattling and wouldn't start well once warm.

Basically it ruined a perfectly good engine. :(
 

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Run the engine under load but keep the revs down, modern machining is so good that you need to run the engine in asap.
loading the engine expands the rings in the bores producing a good seal and thats what your after.
If you poodle about you will never reap the benifits.
A modern engine will not respond to age old theroies of low loading low revs etc. FACT!
You have only 500 miles in which to perform the most important grounding of your engines life.
Full throttle but low revs without bogging the engine, yet to have anyone tell me this method fails.
Search the internet and see for yourself!
 

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Hmm... I still think this way only works because modern oils save the rings from melting to the bore. You didn't have modern oils all those years ago, so this approach would kill the engine.

But why rely on the engine oil entirely, when you can just give the beast a chance by using a variety of speeds and rev's while avoiding the full load/labouring stuff? The most important thing is to have enough variety so that the rings can bed in relative to the bore .. too little variety means you miss the window and the engine is less good than it could have been... but varying the revs and load is not the same as caning it from the beginning.

Ralf S.
 

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Discussion Starter #16
I'll fill the engine with 15w-40 straight mineral oil since I had 3 cylinder liners replaced(old where scratched), then couple of runs under full throttle...after that, back to garage,shut off engine, try to find any leaks, loose parts etc. might torque heads again then oil change.
Now I wonder after these first 50 miles should I switch to syntetic oil or put new mineral oil and do some 400 miles before switching to selenia 20 K
 
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