Well, found the problem!

[cheekymonkey]

The Supra has been fairly neglected over the last couple of months, since the Evo went *snap* *clatter* *clatter* Psssss (that's the sound of all the oil coming out) *bang*

There seems to be something wrong with this pic: :D

http://i178.photobucket.com/albums/w279/cheekysupra/Evo%20IV/Engine%20Build/1_CIMG0105.jpg

So, we went shopping!

http://i178.photobucket.com/albums/w279/cheekysupra/Evo%20IV/Engine%20Build/CIMG0099.jpg

For the rest of the story, in pictures, click here:

http://s178.photobucket.com/albums/w279/cheekysupra/Evo%20IV/Engine%20Build/

We have learnt a lot in the last few weeks, I can tell you...

[carl0s]

How does that happen then? If you had pre-ignition that would push the piston down causing damage to the upper part of the con rod wouldn't it? Or would it? I have no idea just trying to understand.

[carl0s]

Did the piston melt and get jammed in an up-ish position?

[cheekymonkey]

As far as we can tell, or guess, the balancer shaft belt snapped, which somehow starved the crank end of that piston of oil, it then overheated and melted the bearing onto the conrod like you can see in the picture. It's difficult to separate cause and effect though after the fact!

The sump was full of metal shards, it was a hell of a mess. Cost us £2k though and that's doing the work ourselves :(

[Ric]

looks tastey

[DamanC]

Yummy :D

[Chris Wilson]

That is a classic case of lack of oil to that and probably other big end bearings. See the heat that was generated before it filed catastrophically? The blueing of the big end of the rod? Text book stuff. And what long spindly rods as stock!

[cheekymonkey]

Well the rods are no longer spindly :D

Thinking back several months now - this actually happened in July - just before this failure an oil change was performed on the car, and there was a possibility that it was overfilled by maybe half a litre. Wonder is this could have been a factor?

What actually happened was the car was driving up to Santa Pod (in a convoy, not at high speed or anything) and suddenely got a lot of smoke from the bonnet area, pulled over and a LOT of oil had been pushed out of the dipstick, all over the engine hence the smoke. Towed back home, stripped the timing gear off and we saw that the balancer shaft belt had snapped... and the rest of the story is a the rebuild.

It's hard to know what the root cause was but I'd be interested in hearing your ideas guys, now that it's all back and working again!

[neil tt]

:oops:

[Chris Wilson]

I'd need to see all the pistons, but from what you have just said maybe it had ring or piston failure, maybe after detting, blew enough oil out to compromise bearing lubrication, or semi seized and SQUEEZED the oil from the boundary layer, and did a big end. I was assuming it only had bearing failure, was there any indication of piston pick up or seizure on that cylinder? Was it modded to run more than stock boost? ;)