Project Avant+

[terrybullwon]

Bolts look like they have had some heat to, maybe the rod was tight on the crank jornal?

[S2central.net]

Attached perhaps, but torqued and clearance checked ? Surely if not, it would have sounded wrong from the outset.

Did a valve bind up in the guide causing the piston to make contact sufficiently hard enouigh to bend and break the rod ?

Very odd one this - I can't root cause it from these few pics - sure I can see the carnage - and its mighty carnage for a rod to break free like that and gouge the crank.

Nasty - this needs proper root cause analysis before anyone attempts a rebuild, and IMHO the stripdown needs to be carefully documented and photographed in stepwise fashion - otherwise you might never find out what went wrong.

[Ross]

I'm not speculating as to the cause of the failure or putting blame anywhere... to be honest, I have no clue what to think! It's a right mess, and is obviously a rod failure. Any thoughts as to what could cause such a failure and I'm all ears!!

The rod was SPM H-beam rod, I've dug around and not heard of any failures on them and there's some 1000HP+ engine running them. The bottom end proved itself for nearly 10,000 miles when it was in my coupe; then again alot of time has passed since then and other than the rods and crank it isn't even the same bottom end any more.

When it let go, it was at ~3,000 rpm - about 80 on the clock keeping steady speed. Right before it let go there was a subtle rattle - there was ALOT of vibration because of the solid snub mount so it could have been there a little while before i noticed - and then there was a pretty harsh thud, lots of blue smoke and zero revs...

not sure where I go from here, anyone want a nice Avant shell??

[Laurel]

Evening boys - nice to see some support for Ross!

Darling, stop feeling sorry for yourself and posting sad pics on the forum.

It's late, come to bed and I'll give you some compensation.

[s2_bo]

That sounds like an offer you cant refuse mate!

I might have to lock this thread down before it gets out of hand :mischeif:

Enjoy

[Greg_S]

Sorry to hear about the continuing troubles with your motor and like has been suggested a piecewise disection of the engine could prove to be very useful in diagnosing the cause of the failure.

Sounds like married life is treating you well though

[magarv]

I'm very sorry to read this...

From what I can see in the pictures:

There is sign of extreme heat around the main bearing end of the damaged rod. You can clearly se how the colour is changed. I think this is a main bearing failure, either clearance or lack of oil. It is also visible on the cranck. I think this has caused a complete lock in the bearing = rod failure.
How are the other 4 rods/bearings/crank taps? Any sign of wear/damage?
How many miles since rebuild?

Magnus

[audiman]

What a mess!! Looks like the cap was on securely tho. The heat marking is due to the fact that the big end bearing had clearly broken up, casuing excessive heat, hence the marking (to be expected).

A piston hitting a valve would not cause a rod to fail. It would just bent the valve and mash it into the head. The reason i suspect that there was interference with a valve is the fact the big end shell wasnt there to hold the piston away, plus when it broke free if it was moving up the bore at ??m/s it would come into contact.

To find the casue of that failure is almost impossible. The whole bottom end is a right off. Once a failure like that has occured, I would recommend starting all over again. Not the cheapest option, but its one that would work! For example any good bits left like oil pump will be full of swarf (ditch it), the other 4 pistons need to be checked, not sure what pistons you have in there (same new Mahle ones i fitted??) as they could only be bought in a set of 5, and obviously rods. Oh and the block is ******ed!

Why dont you send a picture of the rod to SPM to see what they think from the pics caused its failure?

To me it looks like an unlucky failure. I wouldnt like to point blame towards anybody on that one. I know a lot of people dont like/trust the person that built the engine, but I cant say from what i can see it was his fault.

As for bearing clearances, you cant check that anymore, due to the slight wear issue on both crank and rod

[Fat Audi 80]

Unlucky Ross, really sorry to see your engine in bits again.

I still can't understand why this took 6 months to come to light, but that's your business.

We were all looking forward to seeing your car finished too. (although obviously not as much as you were).

Keep your chin up mate.

Cheers,

Steve.

[Rusty]

Bad luck Ross, looks like a right mess, feel sorry for you, especailly after all the crap over the last 18 months. Perhaps it's time to regroup and get a standard engine back in so that you can drive it again and remember why we all love these cars so much.

Hope you get it sorted, chin up, we're all routing for you!

[newsh]

Holy Merde!
Thats toast..

[shark_90]

Bad luck Ross, looks like a right mess, feel sorry for you, especailly after all the crap over the last 18 months. Perhaps it's time to regroup and get a standard engine back in...

My thoughts exactly. Get a standard engine back in it, get a remap, and start enjoying the car again even if it is minus the BHP you wanted. To be honest my Avant's only got a homefries and although some more BHP would be nice it's a very capable car. Get a standard engine in it and learn how to drive it and love it like that

[s2driveruk]

nothing much else to add mate, hopefully you are reaching some kind of agreement in the background with the right parties? The idea of sending those pics to SPM sounds like a good one IMO...

Good luck with Plan B....whatever shape that takes!

David

[audiman]

My thoughts exactly. Get a standard engine back in it, get a remap, and start enjoying the car again even if it is minus the BHP you wanted. To be honest my Avant's only got a homefries and although some more BHP would be nice it's a very capable car. Get a standard engine in it and learn how to drive it and love it like that

LOL, stock engine. WTF, can you not tell from what he is doing, that a stock setup is nothing like what he wants??

[shark_90]

LOL, stock engine. WTF, can you not tell from what he is doing, that a stock setup is nothing like what he wants??

Indeed, LOL, WTF, ROFLMAO and other associated acronyms.

I'm sure it's not what Ross wants, but I'm also reasonably sure he wouldn't mind driving his car? An S2 with a standard engine is a capable car and can be driven very quickly. Any muppet can go fast in a straight line, I had more fun chasing a mate of mine in a Gallardo in my 1.8T Mk4 Golf+Revo than he did driving a Gallardo and not being able to shake a shonky V reg Golf off I assure you.

It was just a suggestion. BHP figures are impressive etc but nothing more than pub ***** size when it comes down to it. I've read a lot of Ross's posts and although he wants a very potent motor he doesn't come across as the pub chat BHP figures kinda guy... hence my suggestion of having his lovely car back with an engine that doesn't eat itself and he may get a little more enjoyment out of it that he would do if it were sat quite literally gathering dust.