Possible dead engine :( edit: new engine on way :)

[Rs4mar]

All they know at the moment is what I've shown you in the photo. They can't establish any more information without removing the engine. They haven't told me more than one rod had failed until I received the picture this morning and they just don't know how much more damage is done until some more investigation has happened.

[ArthurPE]

from the pictures
looks like the crank end failed, rods did not break
either caps worked loose or bearings worn and got larger creating some slop
on the rod on the right side of the pic you can see wear: this is where it may have rubbed the block from bearing play/loose bearing cap
either way, this is not abuse but a manufacturing or assembly flaw my wag
now a sustained over rev may cause the cap bolts to fail or work loose but imo this would have to be a severe, sustained condition

looking at the pics again, hard to be sure, looks like only 1 rod failed, we are seeing both sides of the upper bearing journel with the bolt holes and locating pins

[adsgreen]

I agree that an over rev can break the rods but on engines like this (and I would absolutely stunned if the RS4 engines wasn't interferance given the compression ratio) it generally mashes the valves first as the springs simply cant pull the valve out of the way quick enough.

Stunned if the end caps would work loose - thats something I've never seen or heard of. Granted, all is possible though.
Only time I've seen worn bearings is from :
- engine builder not torquing and measuring the cap bolt stretch properly so the bearing moves with slop. In this case failure happens pretty quickly.
- complete breakdown of oil - either over heating, too old, no pressure or wrong stuff.

The thing that is bugging me is the 3000 miles since service... There must be some oil left in the sump or cooler somewhere. Would be interesting to see if it held up. Also the crank bearings usually have tell tale burn scars if the oil has failed in someway.

Agree though - rubbish pics. I can't believe that they have had the engine for this long and not simply removed the sump? it's trashed anyway and is not a big deal once the car is up on ramps. There may be other failures that haven't bust through the sump.

[adsgreen]

One other thing - with worn or sloppy bearings or some that are on their way out you generally get the very loud classic knocking sound.
Usually it's bad enough that anybody would know "that is not a good noise".

[adsgreen]

The other thing - need to see what state the cylinders are in... If the rod failed relatively cleanly then the cylinder walls should be relatively undamaged (apart from some localised bit when the rod let go).
If there is a huge amount of scraping damage on the walls then it could have been a piston ring failing causing the piston to overheat, sieze and simply overstress the rod.

[Rs4mar]

That knocking sound would be 'pinking' right? I had that a long time ago on a old nova I had (first car) and it definately didn't do that on the rs.
You were saying about oil temp, what is a normal operating temp for these cars?

[535dboy]

I wish I had a clue as to what you are talking about!

[RIV]

I don't think pinking has anything to do with problems discussed regarding knocking

[Rs4mar]

Sorry my bad, your right, the knocking I had on my nova was the big end bearings and was very noticeable. Don't know why I thought that was pinking?

[adsgreen]

Pinking sounds more like a fizzing noise. Like if you put your war against a fizzy drink bottle
Slightly more extreme is detonation which can easily kill con rods.
Both of these only happen under load really

The knocking I ment is when the bearings fail an sounds like a bag of spanners.

[Batfinnk]

Pinking is more of a light clattering noise and you hardly hear of it these days since the move away from carbs and manually adjusted timing tbh.

[Rs4mar]

It was definately neither of those (pinking or big ends) they are supposedly starting on removal of the engine tomorrow so hopefully some more news soon.
Does anyone know what the normal operating temp is for oil? ie- once the car is up to running temperature?

[PetrolDave]

Does anyone know what the normal operating temp is for oil? ie- once the car is up to running temperature?

I've seen anything between 95 and 115 Celsius on the DIS, depending on outside temperature and how hard I am or have been driving.

[Rs4mar]

Does anyone know what the normal operating temp is for oil? ie- once the car is up to running temperature?

I've seen anything between 95 and 115 Celsius on the DIS, depending on outside temperature and how hard I am or have been driving.

Mid 90's seemed to be my average, never saw it go above 103 so that's good to know thanks

[ArthurPE]

you can definitely see the cap on the crank end (big end) of the rod is missing
you can see the bolt holes and locating pins

imo a failure due to oil issues would have siezed the crank and broke a rod in the middle
this rod failed at the crank connection, not broke in the middle or at the piston pin

pinGing is Pre-IGNtion (not pinking, unless that is UK jargon) or knocking, firing due to
as opposed to detonation