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not sure, the machine shop can decide. the mains are pretty bad though and there is scoring so odds are it throw away. probably bent too, they normally are after this sort of thing.

this isnt meant to be the report my engine failure thread though, I'm sure there is one of those somewhere....

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pulled the motor apart today, the the main bearings were f**ked although not spun yet, and the big ends were almost perfect (just some foreign damage, I guess as the mains died). Good call Dan

so 1 point to the oil analysis.

Does anyone have results for a motor just after run-in?

Who left the main girdle loose? That's about the only way you could do that kind of damage - either that or incorrect clearances.....like miles off

Duncan, change your engine builder and I guarantee all of your engine failure worries will go away. Its not just about how they build, its the advice they give that prevents these things from happening.

My first engine failure with them was the same sort of thing - bad clearances.

2nd was due to crap in the cooling system - my radiator literally came back brown and overheated cracking a head gasket.

3rd was bad rings (my theory is they re-used the old rings and only swapped over the head gasket when it blew).

In the end you can only blame yourself for taking it back to the same place. You will probably delete this post, either way its food for thought.

Joe, the shop you are thinking of have never built a motor for my race car. They have built 2 other motors for me and both are lasting well. And I'll never delete a post unless it breaks a rule :D

Dan I'm waiting for the engineers report...the workshop beleive oil starvation would affect the mains but not the big ends (initially). I don't understand that point of view so I had a 3rd party look into it.

Joe, the shop you are thinking of have never built a motor for my race car. They have built 2 other motors for me and both are lasting well. And I'll never delete a post unless it breaks a rule :D

Dan I'm waiting for the engineers report...the workshop beleive oil starvation would affect the mains but not the big ends (initially). I don't understand that point of view so I had a 3rd party look into it.

Yeah... NAH!

Big ends always go before mains, look at all the GTR's that crack their oil pumps. Big ends die, not mains!!!

"Elite racing" sound like they are on the right path, either loose girdle or massive clearance issues

^^^ yeah i lunched a one in cats car due to a dodgy sump and pickup arrangement (ASR or high energy built me one that fixed the issue) and it burnt the big ends due to oil starvation. soon as it (rb26) spins a bearing the cranks bend like a bannana and often crack near the radius.

Ive havent seen a 26 with damaged mains after oil starvation unless it was driven for an unreasonable distance.

Does anyone have results for a motor just after run-in?

we dont do engines anymore (no time) so dont do any more oil analysis, but based on previous experience after the first oil and filter change our are pretty close to being normal (no excessive anything) in all instances.

damn, id be depressed if i went through as many engines as you have :( good on you for keeping a positive attitude though!

i know some ppl that get depressed if their fuel pump decides to die and that's nothing compared to what your dealing with!

just a quick Q, what was your oil pressure like before you pulled the motor down as compared to when it was a fresh engine? ie did u notice a gradual drop in average oil pressure levels between track days?

Edited by snozzle

was about to ask this. surely putting the block through the hot tank would wash any old bearing material out?

or would sum of the oil galleries be farely hard to clean out?

but then again when u pull a block out of the hot tank you blast the shit out of all the galleries with the compressor so surely that would quiet easily blast out any shit the tank missed

Dave (and everyone else for that matter) this thread is not about why my engine failed. That discussion will take place off the internet with the workshop involved.

This thread is about oil analysis, and what typical and atypical results look like.

Hi Duncan do you have a local WESTTRAC,

as they have Sampling service & for $26 is a great price,

even if you get it sent & have then Email you result`s,

Duncan, thats good news about the workshop, i stand corrected on that matter. Either way you made the right choice!

Dave (and everyone else for that matter) this thread is not about why my engine failed. That discussion will take place off the internet with the workshop involved.

This thread is about oil analysis, and what typical and atypical results look like.

this may help;

http://www.oil-lab.c...sis_Reports.pdf

this guy's website is quite informative in terms of giving acceptable limits. there is also a forum where you can submit your oil analysis and get some feedback too.

http://www.bobistheo...id=50&Itemid=56

forum:

http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=postlist&Board=3&page=1

Edited by SECURITY

I have the results for Noels engine after 500km (same oil the whole time) and from memory the lead and copper were both under 1ppm

Iron was about 25 or so (which you'd expect from ring bed in)

I have the results on the computer at work so if I get a chance/remember, I'll post them up

Any amount of lead is bad. The crank should not make contact with the bearings so the lead should be virtually non existent unless there is something chewing away at the top layer. Every 'oil starvation' failure I have seen has always shat the big ends, never the mains. The only time I have seen mains wear on every single one is:

A: Customer fit clutch incorrectly causing the crank to be locked against the gearbox (twin plate). After 10,000km or so the thrust bearing took it's last rotation. ALL the mains were completely gone

B: Girdle left loose by previous engine builder - every main was cactus

Oil starvation will wear journals 3/4/5 first but due to the fact the mains feed oil to the big ends, even when starved, the mains are the first to get oil again and the big ends get starved more. Also due to the fact the big ends have 100 x the load on them and the squishing effect removes oil very quickly. It takes A LOT to blow every main. Then you said you have every big end pretty much ok. That tells me something was wrong with the mains, not just something WENT wrong.

I know this isn't supposed to be an engine failure thread but hoping to give you a better understanding of what may have caused it.

I personally use Wear Check Australia for our oil analysis. They cost ~$40 and are pretty clear to read. The results you showed were clearly engine fail but they suggested that it may have been normal for a running in engine. Lead and copper are big fail indicators. Iron not so much

As I'm just about to run an a new engine i was wondering what the advantage is in testing run in oil, as you would expect there to be all sorts of metals (EDIT! I mean High Levels) in there as things bed in (obviously you don't want to much bearing metals though). If you were only going to do one analysis would it be better to do it on the first change or say after 500-1000km's?

Edited by D_Stirls

Not really. On the first one you will see higher levels of iron but nothing too serious. If the engine is assembled clean, then there should be nothing more than that.

Doing an oil test after the first oil change (at say 500-750....or even 1000km) is probably the best way to go about it. Also with run ins, whenever I build an engine for a customer, I always do road run in. Dyno run in works but you need to factor in problems that may not appear in the first few hours of engine operation. Leaks etc. Take it slow. Do small runs at first and gradually go further after each check. Never leave the engine in one load point...always be accelerating or decelerating, never stay on cruise for too long and never idle for long. After 500km not so important.

If you change the oil at 500km, you can drive it 100km more and do an oil test then if you like. Make sure you take the sample just after the engine has reached op temp otherwise any particles will settle. Never poke the tube all the way to the bottom of the sump either...for the same reason.

You get the results back in a few days and hopefully you'll be near 1000km by then and ready for tuning

  • 3 weeks later...

Well....since the new build is finished I guess I will have some figures to post in the next few weeks, I intend to get the run in oil checked for interest. Will also check the proper oil after run in, tune etc.

BTW failure reason for the old motor was identified, a bolt head from the cam baffle bolts were found in the oil pump intake. Also explains the high (5x) iron on the oil analysis

interesting about the e85 and oils..

those running e85 what engine oil do you recommend for a high hp rb25?

very interesting, i dont think many people know about this, id be interested to no what oils people are using too, as i was considering a which to e85 now that i have a pump near home with it.

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