hello,

 

please could someone help me on this 2 things:

 

pistons:

http://japcardijon.free.fr/piston.JPG

they ae wiseco and they did less than 2000miles. What are this light mark?

 

top timing belt pulley:

http://japcardijon.free.fr/toppulley.JPG

pulley is less than 2000miles and belt is less than 300miles.

Where the mark come from?

 

thank you

not very good pic of the bores what mark are you on about? weisco iv seen several circlip failures i wouldnt use them personally but thats me, is the bore scored?

 

as for idler the marks look like belt rub and has left it on the idler, iv seen lots like this and not normally a problem, if its new does it spin freely without any noise, if its fault it could potentially strip the belt.

You will always get carbon build up on the pistons, are they pitted?? could have also been detting?

 

Not sure what has caused pully to mark like that, was it a genuine nissan cam belt? poss tightened too much?

 

Mike

thank at both of you for quick reply.

 

Concerning the piston, they should be all black no? they are not pitted. that light mark is all around the 3 pistons and i was wondering if it was detonation? What cause detonation?

I've jwt500, 555cc and run around 15psi (on stock FMIC) of boost as i was having a boost leak.

Tomorrow i will open the other side to see.

 

The belt is a reinforce one. The pulley is like new and no noise or neither

thank at both of you for quick reply.

 

Concerning the piston, they should be all black no? they are not pitted. that light mark is all around the 3 pistons and i was wondering if it was detonation? What cause detonation?

I've jwt500, 555cc and run around 15psi (on stock FMIC) of boost as i was having a boost leak.

Tomorrow i will open the other side to see.

 

The belt is a reinforce one. The pulley is like new and no noise or neither

 

TBH i have had another look and apart from the carbon build up which is normal they look fine, are you losing and pressure through the pistons or rings?

 

Detting can be caused by various things, bad fuel, bad mapping etc etc difficult to say.

 

You say a "stock fmic"??? you have a front mount or not? or do you mean stock side mounts? if you have stock sidemounts then thats poss where your going wrong as your side mounts will not be good enough for bigger turbos running 15 psi

 

Mike

the light mark is on the inlet side of the combustion chamber i would say the light mark is due to the fuel going in and washes the piston clean before it ignites or where its flooded or been flooded with fuel.

 

the mark on the pully might just be the surface coating of the pully coming off? try to see if it will scrape off

sorry wanted to say SMIC lol

now i'm going with udge FMIC ;)

 

You made me think about on things.

You said the mark are on the fuel side. Can it be because of wrong timing?

But you are write, 15psi with jwt is not a good set up.

However, i have also 555cc injector but not 100% sure they are. In France, nobody do flow check :(

But i run a 555cc single pop eprom from dta. Could it work if my injector were 370 or highr than 555cc? hpe i'm clear enought :D

 

 

Concerning the pullay, i removed all the mak, it was like plastic.

not very good pic of the bores what mark are you on about? weisco iv seen several circlip failures i wouldnt use them personally but thats me, is the bore scored?

 

 

Hmmm that is exactly what happened to my engine block! :(

the light mark is on the inlet side of the combustion chamber i would say the light mark is due to the fuel going in and washes the piston clean before it ignites or where its flooded or been flooded with fuel.

 

the mark on the pully might just be the surface coating of the pully coming off? try to see if it will scrape off

Carl is right the clean part of the piston is caused by atomised fuel cleaning the piston.the rubber build up on the idler is what happens when the belt was too tight as Mike said.

Hmmm that is exactly what happened to my engine block! :(

yeh i know stu, and one of ryans :cry:

sorry wanted to say SMIC lol

now i'm going with udge FMIC ;)

 

You made me think about on things.

You said the mark are on the fuel side. Can it be because of wrong timing?

But you are write, 15psi with jwt is not a good set up.

However, i have also 555cc injector but not 100% sure they are. In France, nobody do flow check :(

But i run a 555cc single pop eprom from dta. Could it work if my injector were 370 or highr than 555cc? hpe i'm clear enought :D

 

 

Concerning the pullay, i removed all the mak, it was like plastic.

 

i dont know what happened to you engine or what symptems you had, i think you been over fueling, you got 555 injectors? or poss stock injectors but the ecu been re-mapped for 555 injectors? its also possible someone has bypassed the fuel pump control unit? this allows the fuel pump to produce the right fuel flow to the injectors. If it has been by-passed it will only give high fuel flow to the injectors, hence over fueling is possible

so in my case i'm overfuelling?

so in my case i'm overfuelling?

 

its difficult to say bud, why have you removed the engine etc anyway? there must have been a reason? and symptoms?

 

with regards to the chip, the jwt is a very good chip but is it the right chip for 555's? do you deffo have 555's?

 

Mike

ok so i've open the engine to change the crankshaft.

This morning everything is open and othe side of piston are ok.

Crankshaft, bearings and rods (eagle) are dead :'(

 

I'm waiting on Toga bearing and will put back the old (stock) rods :(

 

The ECU come from DTA motosport and is for 555cc injectors.

What i don't understand is why one side is ok and another on look to rich?

ok so i've open the engine to change the crankshaft.

This morning everything is open and othe side of piston are ok.

Crankshaft, bearings and rods (eagle) are dead :'(

 

I'm waiting on Toga bearing and will put back the old (stock) rods :(

 

The ECU come from DTA motosport and is for 555cc injectors.

What i don't understand is why one side is ok and another on look to rich?

 

Jesus how did you toast the rods etc??? i presume the oil pump failed?

 

ECU wise it all depends on how its been mapped, as someone has said one side may have been getting enough fuel but by the time it feeds round to the other side it may not be getting enough fuel which could be the fuel pump or ecu etc

 

Mike

If the fuel pump was running at full whack then it wouldn't overfuel - thats why you have a fuel pressure regulator - it returns surplus fuel back to the fuel tank!

 

How many miles are on those pistons? They look fine to me, although possibly the engine has been 'breathing' quite heavily (excessive blow-by gases).

 

I presume the rods are toast because you carried on driving the car with the bottom end ****ed? Thats what happened with mine :D

>> I've jwt500, 555cc and run around 15psi (on stock FMIC) of boost as i was having a boost leak.

 

the overfueling on the LH-bank might very well be caused by this boostleak

I wouldn't be surprised if there's a (big) leak in the RH intercooler/piping.

 

-Eric

you are right, there were a hudge leak (because i removed the stock solenoid and mess up with the piping)

 

what's happen first is that on track, i kept driving while (because i didn't see) the left hose of oil return was cut :( :( :(

 

So then, i open the bottom and changed the bearing but rods were blue. I did 5 miles and toc toc toc again.

So now, I'm rebuilding again but old engine was less than 2000 miles :(