[scorgio]

1st of all this is a 4 piston diesel engine. As you can see from the pics, the piston literally exploded. Bearings crooked. Conrod slightly bent. So what I wanted to know, what caused this? Shoddy workmanship? Material defect? Or you name it.

1) The exploded piston, 3 of 4 rings snapped, pin & clip still in good condition. The crooked bearings on the top left.


2) The carnage.


3) Some left over pieces at the oil sump.


4) The explosion caused a crack at the oil sump.


5) The cracked piston.

[scorgio]

6) The top of the piston, can see signs of piston hitting against valve. The logo of the piston brand in the middle of the pic.


7) The exploded piston was on the 2nd cyclinder. But somehow the 'color' at the head is different from the other 3.


Appreciate constructive comments.

[byebye2u]

wow bro, sorry to see what happen to your ride.

is it common rail? 2.5?

any modification for performance?

the 2nd block/piston looks clean, some water must have gone tru. water + diesel + turbo pressure + diesel compression ratio = disaster . once the water goes in the block at extreme condition it will immediately vapour and give an explosion that can shatter the piston. most probably coolant go tru broken gasket.

other cause :-

http://www.machinery...il-contaminants

[ycfoo]

wtf!!??!?! , this is 1st time I see a piston can blow like that?!?!?

if we didnt modify the engine, turbo & etc. A full stock engine is hardly can be like that... like byebye2u said may be there hv water went into the system.

[rallychamp]

maybe water..(or gasket related)


maybe due to clogged injector and that piston running very very very lean thus making it so brittle and explode during power-stroke....common on boosted petrol ride....but seeing this on diesel ride....a rare occasion..




i've kena like this on my daily ride scooter...lean carb mixture valve also gone kaput....

[darreltian]

maybe water..(or gasket related)


i've kena like this on my daily ride scooter...lean carb mixture valve also gone kaput....

running to lean meaning u adjusted the AF ratio?
as i know most cars running more smoothly on lambda 0.9 (10% excess fuel)...
reducing by means of air bleeding will creates higher operating temperature

[tom33]

running to lean meaning u adjusted the AF ratio?
as i know most cars running more smoothly on lambda 0.9 (10% excess fuel)...
reducing by means of air bleeding will creates higher operating temperature

what car is yours??? can any one tell me reg proton wira disel???/

[chargerguy]

Most likely due to coolant or water sip into cylinder no2. Back pressure and cause the conrod bearing to fail and shattered...


1 cent

Cheers

[kingDIY]

based on my experinces seeing many piston damage, i believe this could be likely due to material failure which lead to shattered piston up to that extend.

if ring broken or foreign object went into chamber, likely the piston will get serious cut (vertical) but remind intact as one piece.
if conrod break, movement of piston stop & piston would not be that bad, probably a big hole on top part.
a good quality piston, regardless what broken inside the combustion chamber, it wont badly damage up to that extend.