[Mk2] [Turbo] over fueling

[ashley]

Are you sure they were they new when they went in?? Might explain why they were cheaper?

Is that similar damage to the original pistons you had to replace??

Is there any sign of damage on the crowns?

[sawicki]

yes they were deffently new the first time the rings were broke as well. there is no damage on crowns.

[bobhatton]

That is bad detonation that has caused that, never seen it so bad on the side of a piston before.

Was it number 3 cylinder?

[sawicki]

yes cylinder number 3

[ashley]

How did the other 3 pistons look?

[sawicki]

prity much the same but piston ring broke as well and scored cylinder that was also on same cylinder.

[ashley]

Sorry- I meant how did the pistons from cylinders 1,2 & 4 look this time around- were they damaged as well?

[sawicki]

no damage to other pistons or piston rings. however since the first rebuid it has been uesing oil the engine rebuilds told this was usual after a rebuild.

[ashley]

I wonder if you've got a partially blocked injector on that cylinder...

[sawicki]

injectors have all been tested and are working as they should

[Andy F]

ringland.....too much boost, simple as!

[ashley]

So must have been running more than 1 bar then....?

[sawicki]

found the problem wrong pistons

[ashley]

What was wrong with them- too small?

[sawicki]

original ones were dished and the ones the engine rebuilder put in were flat

[Jim Galbally]

sorry i dont understand, im no MR2 specialist but looking at a pic of those standard pistons i cant see how you could have fitted flat pistons that were suitable?

still, what was the reason you got the engine rebuilt in the first place? did you rectify the cause of the initial failure or did you just replace the broken components and put it back on the road?

lots of people have afault whch causes an enine to melt, fix broken engine but dont fix fault that caused it to melt in the first place then very quickly melt the newly rebuilt engine!

[ashley]

original ones were dished and the ones the engine rebuilder put in were flat

I'm confused...I thought your engine was on standard internals? The pistons I posted are standard rev3 tubby pistons and they are flat? (albeit with valve cut outs)

Have you actually got the original pistons that came out of your engine to confirm what they have told you? Sounds like you might have a different issue (high boost) and the engine builders are trying to get round it by fitting lower compression pistons this time...

[sawicki]

i have had both original and ones that were fitted this time and there is a clear difference and as for people saying too much boost its not as when my engine went first time it was compleatly standard i only turnd boost up to 1 bar after first rebuild.

[ashley]

Cool- maybe the pistons that came out of mine weren't standard then...

Hope it goes better this time mate

[sawicki]

cheers
got to try and get engine builders to admit it were there fault as i took it to a different company to ask there opinion and there the ones that found out they were wrong pistons.