running in new engine

[GazzaG60]

i have only ever built them myself. not many but i like to know its my fault if it goes wrong.

in that instance id want to know the measurement of bearing clearance by the builder. engine build lube goes more or less straight away. washed away by oil. packing the pump with lube at buid helps the pump create grest pressure straight away rather than the airlock then oil. maybe that too.

i know of lots of builds and i have not heard of that one on vag 16v or 20v before.

[S2central.net]

I recently read an expert analysis of an engine failure, whereby the route cause was the melting of a big-end bearing (and consequent failure of the conrod) which was described as most probably the cause of hard driving before the bearing surfaces had sufficiently worn in (and thus absolving the engine builder from any responsibility). Might smell of BS, but such a report could be a sting if you ever have an engine failure during run-in...

WIth all respect - I think that is balderdash... More likely scenario is the incorrect bearing shells were chosen (and/or crank machine ops were inaccurate) and there was improper clearance - which caused excessive friction and/or oil starvation then a cooked bearing which seizes up and turns a conrod into a banana. Trouble is - if someone else builds your engine then you are trusting them totally to do this correctly.

Had the bearing clearances been stated as part of scope of works / spec for the builder then the other bearings could have been inspected to help ascertain if the requirements had been observed.

Those bearings are hardened at manufacture - not during run in period.

Other possibility is simply flawed processes used to harden the bearings - maybe a bad batch or something like that from a factory.

[Jamo]

Repo I hope you don't mind me posting

Put in turbo diesel (really, these oils have good cleaning properties) oil for initial start-up. Run warm, give some revs. Let cool down. Retighten head bolts. Check for leaks and loose stuff, like bolts, brackets, etc. Run hot twice more, let cool down. Recheck

Make one mile testdrive WITH VACUUM ONLY, check for leaks, loose bolts, clamps, stuff.

Make ten mile testdrive WITH VACUUM ONLY, yet altering load levels and revs. Check for leaks, loose bolts, clamps, stuff.

Change oil and filter. Put real stuff in this time.

Drive around for some hundred miles or so, apply _some_ boost with moderate ignition timing. Stay safe with air / fuel ratio, but do not flood, as constant rich mix ruins oil faster than most people realize. In case of continuous or repeating afr of 10:1, fix fueling and change oil before first flat out pulls.

I'd say You are safe to give load to the motor after say, 120 miles or so. Breaking in for traditional 300 miles is unnecessary, if You ask me.

ALWAYS CARRY GOOD SIZE FIRE EXTINQUISHER IN THE CAR WHEN BREAKING IN.

[GazzaG60]

which as we both mentioned would be picked up on the build measuremetn sheet if done by a pro.

i didn't measure my clearances but like i say i wasn't paying somebody else to build me an engine.

[GazzaG60]

makes sense that jamo. from a known good source too. not to overly cautious but not biting off too much to start with.

i know running in oil is quite hard to come by now. i got the last 2 bottles from my local supplier that he could get.

a cheap plain mineral diesel is similar. have heard of similar used as a routine flush too.

[Audi_CQ]

I wish people would stop posting that crap motortune link, it's complete piss.

Ask Repo for his running in guide it's what I and Terrybullwon will be using.

I don't know you so have to ask: Why is it complete piss? Have you done tests that prove it's wrong or? If so: What results did you get when using this method? Any pictures of ruined engines or maybe leakdown test showing rings not sealing after running in hard?

Consider this: diesels are always running with "full trottle" and high cylinder pressures. They are known for their high mileage aren't they? Maybe high cylinder pressure from the word go isn't so bad?

In the end everyone has to think for themselves and decide who they trust (if they don't have own experience).

I opted for motoman

[terrybullwon]

i am with jamo.... repo has built the fast il5 in the world. if its good for him its good for me.

[GazzaG60]

there are lots of correct ways and a few bad ones.

mototune has been used by many before with good results but i feel its better for bikes and cars with alloy blocks. we can afford to take a little more time.

id like to know why its complete piss too

[Jamo]

there are lots of correct ways and a few bad ones.

mototune has been used by many before with good results but i feel its better for bikes and cars with alloy blocks. we can afford to take a little more time.

id like to know why its complete piss too

Search the yank forums around the world and see what they think of mototune

End of the day your engine run it in how you like but i've spoken to Aelred, MRC, Audiman, Repo and a few others and all their methods are near enough the same and nothing like mototune.

Now seeing how they build I5 engines and not bikes I trust them more than mototune!

[mcandmar]

Both arguments are valid, its true you want to keep the engine under load to bed the rings in, worst thing you can do is sit at part throttle/light load cruising down the motorway. On the other hand you dont want to subject the crank and big end bearings to high loads until they have bed in. Cams/Valve gear also need a little time to bed in before you subject them to high revs. I agree with Jamo in relation to mototune, that link has been around the net for years and is generally considered as tosh.

Personally i would run with the WGFV disconnected and drive up/down hilly roads all day long varying load and engine revs. Make it work but have some mechanical sympathy too.

[GazzaG60]

thats fair and i dont disagree with you but for you to say its complete piss would mean there is nothing right at all. a bike tuner i spoke to said it made sense so its not complete piss but for the brave on an i5.

i did mine at can pressure as previously stated part load. quite similar to the general way of things as i too sought the knowledge of the"pros" 16v pro's but its the same ****.

the last subaru we did was run in a little harder due to the alloy block. the bores smooth on those easier and sooner.

its a strong statement "complete piss" thats why i and i presume Audi CQ ask.

[Jamo]

It's a strong statement I stand behind it, I do not know of a single tuner that I have spoken to that will endorse mototunes method and then stand by it incase of motor failure.

As I said if you want to use the method please go ahead.

[GazzaG60]

i have no need to mines fine.

not having a go at any tuners here but i would not put my reputation or my cash on the line risking a brisk run-in for top seals. better to have a a fully working engine. in true race world the tolerences are so good that i think some do but as stated by others they rebuild often too. and have **** loads of cash.

the cautious side of me would not allow instant pedal to the metal anyway. i like to see an engine idle up to temps first and the fan kick in. after every job that involves dropping water i do that.

one point i think is very good in repos message is the overfueling one. overfueling aint good as he states. washes the bore and can make the rings brittle along with piss oil.

[s2martyn]

this is what i have done over the last 2 days...i have covered 210 miles with no problems so far.......
started it up and made sure i had no leaks(tickover)
held it at fast idle(2000-3000 revs)until it was up to temp...let it cool for 30 mins or so....
started again held at 2000 again but with a few blips this time
took it causiously round the block,back home and let it cool
took it for a good 5 mile spin with n75 disconnected..let it cool...
did 50 or so miles driving normal
then i reconnected the n75
the rest of the miles have been covered using no more than half throttle with the occasional 3/4 to full throttle now and again....
the engine now feels looser than when i first drove it.....
i have not drove it continuosly just kept stopping and giving it a minute..
there is a lot of lag,thecar is running a gt35 with twin intercoolers and the boost doesnt start until 4000rpm so i havent really put too much load on at this stage...
next step tomorow is to get the oil warm and drain it and change the filter.....


my question is now which oil shall i use?more mineral?semi synthetic or fully synthetic...

[Audi_CQ]

Search the yank forums around the world and see what they think of mototune

Do they have any tests that shows that the motutune way is "complete piss" or?