breakin milage?

my engine rebuild is soon coming to and ending and it will be installed this weekend.

Question is, how many miles should I put on it before applying any boost and new mapping

it's a seasoned block, that's been very slightly honed and build with aftermarket rods, pistons and bearings, and another used untouched crank.

Top has been polished and has slightly stiffer springs (newer stock)

what you recon?

I did around 800 miles, no boost on a synthetic oil, then changed oil full torque check and started to increase the boost over two mapping sessions

which bolts did you torque check, and did they take any tightening?

which bolts did you torque check, and did they take any tightening?

Head bolts I think, was all done at Phoenix

Mineral oil for the initial break in - let the rings bed in, otherwise you won't get a good ring seal.

When we did my bro's we did an initial 50 miles on mineral oil, changed it and the oil filter to get rid of any potential crap still in the engine from the rebuild, then again at 250 miles, 500 and 800 miles. Between each change we varied the load on the engine driving all country roads, up / down hills etc. and after the initial 250 miles started introducing some boost as part of varying the load.

At 1,000 miles Silkolene Fully Synth was used again with a new oil filter and at that point it was open season as far as boost goes. We checked compression along the way and the figures were excellent.

Cheers,

Brian.

wow that's quite a procedure!

whats the benefits of using mineral oil over synthetic?

Mineral oil for the initial break in - let the rings bed in, otherwise you won't get a good ring seal.

 

When we did my bro's we did an initial 50 miles on mineral oil, changed it and the oil filter to get rid of any potential crap still in the engine from the rebuild, then again at 250 miles, 500 and 800 miles. Between each change we varied the load on the engine driving all country roads, up / down hills etc. and after the initial 250 miles started introducing some boost as part of varying the load.

 

At 1,000 miles Silkolene Fully Synth was used again with a new oil filter and at that point it was open season as far as boost goes. We checked compression along the way and the figures were excellent.

 

 

 

Cheers,

 

Brian.

Same as Brian, except on first start we have the engine at a medium rpm for a few minutes (2500rpm or so) and we use this time to check for leaks etc etc.

We then do a drain/refill/filter to remove any intial reminents from the build such as bearing and Cam lubes etc etc

Have always done the mineral oil thing which is beleived to be important during the ring seating procedure as Synth oils may prohbit the bedding in of the rings (dont allow enough metal to metal contact) - Though others say using mineral based oils is simply a myth that has been passed down from generation to generation

Others do 1 check over and oil change, then drive it like they stole it

I was eager & with supra being off road for about 4 months run my rebuilt engine done by mark @ Phoenix 1000 miles in one night last year started my run in journey around 9pm & back home by 8am hardly no cars or traffic great run in & used all A roads so was not run in at 1 speed

Same as Brian, except on first start we have the engine at a medium rpm for a few minutes (2500rpm or so) and we use this time to check for leaks etc etc.

We then do a drain/refill/filter to remove any intial reminents from the build such as bearing and Cam lubes etc etc

Good point, forgot to mention that step - we did the same. It's your chance to check everything over and spot any potential issues with poor seals / gaskets etc. before hitting the road.

When a block is re-bored or honed at the machine shop, the rough finish (cross-hatch hone usually) is for exactly the reason of causing friction with the piston rings for those first few miles to let the surfaces bed to each other properly, ensuring a good ring seal and thus good compression in the process. It's a vital step and running synth oil at this stage eliminates the roughness and the bedding of the parts never happens - meaning poor ring seal and so poor compression.

Cheers,

Brian.

good advices.

could you recommend an oil for this?

what do you think of this guys statements: http://www.mototuneusa.com/break_in_secrets.htm

good advices.

 

could you recommend an oil for this?

 

what do you think of this guys statements: http://www.mototuneusa.com/break_in_secrets.htm

Any decent quality mineral oil will do the trick, try to get close to the Toyota recommended 10w30 viscosity but in reality many mineral oils are 15w40 or 20w50. Opie oils on here should be able to supply something suitable if you can't source it locally. There are oils specifically branded as 'run-in' or 'break-in' oils but tbh I think you're just paying more for the same mineral oil.

I've read that mototune article before and agree but would be too chicken to do such a short break-in after the time and money invested in a rebuild. Hence my half-way house longer mileage but varied load from the outset type approach...

Cheers,

Brian.

you can use miller running in oil?

the one I've found is 15w40

however, I've just talked to the builder about this and he's not too keen on running 100's of miles on mineral oil as we've used untoleranced ACL bearings, and he's convinced that even the slightest amount of boost could mess up the bearings.

Also he claims that the issue with the rings bedding in is not that important as todays high performance pistons uses rings that are much thinner and has less tolerance to walls.

He recommends that it's only started on mineral oil and runned for a couple of mins with varying rpms, and then for the street break on, switch for a Synthetic oil.

how does that sound?

you can use miller running in oil?

That's the stuff I'm going to use. The thing is to use good quality mineral oil, not cheapo crap stuff. There's nothing wrong with good quality mineral oil, it just breaks down quicker than synthetic. There's lots of hearsay and mystical stuff about engine break in you find. The engine builder is probably right, I'm not really sure it makes any difference with modern rings and plateau honing. But hey, it's not much more hassle doing it so I figure I may as well. I'll be using Millers break in oil for the first fill and the second after the initial run. Then I'll switch to fully synth after 500 miles or so I reckon.

Also, the famous Motoman method is talking about NA engines when it's talking about full throttle. The equivalent on a turbo engine would be to run it up to 0 on the boost gauge (i.e. atmospheric) rather than give it full boost. That would be enough to force the rings against the bores. The other thing is you need to make sure you have a proper map if you have an aftermarket ECU, fueling etc so it doesn't run rich while you're running in.

yeah, the thing with the boost is an issue as well I'm told by my builder. He opinion is NEVER to make over 0 when running mineral oil as my bearings (as mentioned) are untolerated ACL ones in std size, and therefore the mineral oil wont support them enough to deal with any kind of stress...?

true?