fully built gsr. aebs sleeves 84.5mm, eagle rods. turbocharged t3/t04e 60 trim.
ok so my pistons are cracked. im not sure what happened. it was driving fine on they way to school. i got out of class and came out to start the car and had 0 oil pressure. i shut it off and got it towed home. today i pulled the oil pan off and my pistons are cracked on the skirts and under the dome. then i took the head off and the tops look fine. what would cause that? just confused on what happened. i wasnt getting on it and it blew or anything. it was running fine and then just after school it was done. im assuming part of the piston got sucked into the oil pump and expletiveed it up. motor only had 400 miles on it. this is


Modified by patrick4588 at 6:38 PM 2/5/2008


Modified by patrick4588 at 7:54 PM 2/11/2008

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by patrick4588 &raquo;</TD></TR><TR><TD CLASS="quote">ok so my pistons are cracked. im not sure what happened. it was driving fine on they way to school. i got out of class and came out to start the car and had 0 oil pressure. i shut it off and got it towed home. today i pulled the oil pan off and my pistons are cracked on the skirts and under the dome. then i took the head off and the tops look fine. what would cause that? just confused on what happened. i wasnt getting on it and it blew or anything. it was running fine and then just after school it was done. im assuming part of the piston got sucked into the oil pump and expletiveed it up. motor only had 400 miles on it. this is </TD></TR></TABLE>

is this a turbo motor? did you get it tuned? what is the setup?

 

You have to give us your setup?

Motor?Head?Piston mm?Riding lawnmower?

You didnt give us anything to work with

 

Need pics too.

 

Cracking a piston shouldn't directly effect oil pressure.Is the pickup screen full of piston pieces?

 

its not empty... lol. im assuming it sucked up pistons pieces and locked up the oil pump

 

I have CP pistons in my ls vtec on boost and they are fine. it must be your tune is what im guessing. could be a number of things tho

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by patrick4588 &raquo;</TD></TR><TR><TD CLASS="quote">its not empty... lol. im assuming it sucked up pistons pieces and locked up the oil pump</TD></TR></TABLE>

is it tuned?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by patrick4588 &raquo;</TD></TR><TR><TD CLASS="quote">its not empty... lol. im assuming it sucked up pistons pieces and locked up the oil pump</TD></TR></TABLE>

is it tuned? and if so on what engine management? Hondata? Crome? etc.....

honestly without more details its pretty hard to say what happened. some pics of the pistons might also help. if you take it apart also then pics of the bearings. rod journals. crank. sleeves.. etc... the more details the better. gas you are using. how much boost. have you taken it apart? pics of the sparkplugs. etc...

 

it was just a partial street tune, and never really saw boost. i got on it a few times, but for the most part it was driven mildly. crome pro, 93 octane. only 11psi on a 60 trim. i just have never heard of the pistons cracking where they did, its weird. up under the dome is just puzzling. ill get pics once they are out of the car.

 

The tune is more than likely the cause. I've never had a problems with CP's in engines I've built.

 

yeah no one has really had issues with them, it was just weird to me that they cracked on the bottom

 

Do the cylinder walls shows signs of rubbing from the skirts?

 

no, piston walls are fine and dont show any damage.

 

so you got any updates on this yet?

 

Still no pics???

 

the tops are fine and the ringlands are except for a tiny piece that broke off on cylinder 1. all four pistons are like this. same break in the exact same spot. the skirt broke off. the cracks originated at the bottom of the skirt and went up from looking at them since on one side the cracks are going up and havent reached the ringlands yet

 

Is it possible the piston skirts were hitting the crankshaft counterweights?

 

wow that looks horrible........if it was one piston that cracked like that i would assume it could possible be a defective piston....but you claim to have all 4 pistons cracked the exact same way which leads me to believe either improper machine work and/or installation or the tuning was way off and caused the pistons to expand from excessive heat.

since you say there is no damage to the cylinder walls (which i find hard to believe) i would think there was a clearance/machine/installation error.

OR

CP pistons suck that much?

 

That's more than likely mechanical damage. Even when you blow a motor's ring lands, usually all 4 aren't totally mashed. Plus with no oil pressure, you'll throw the row at the bearing before the piston were to come apart. Check your crank and the piston skirts for appearance of contact. That SUX

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by PyroProblem &raquo;</TD></TR><TR><TD CLASS="quote">Is it possible the piston skirts were hitting the crankshaft counterweights?</TD></TR></TABLE>

they weren't. i have the oil squirters in there and they were undamaged.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by non-VTEC &raquo;</TD></TR><TR><TD CLASS="quote">wow that looks horrible........if it was one piston that cracked like that i would assume it could possible be a defective piston....but you claim to have all 4 pistons cracked the exact same way which leads me to believe either improper machine work and/or installation or the tuning was way off and caused the pistons to expand from excessive heat.

since you say there is no damage to the cylinder walls (which i find hard to believe) i would think there was a clearance/machine/installation error.

OR

CP pistons suck that much? </TD></TR></TABLE>

i was kinda lookin at it the opposite of what you were. i was thinkin if it was detonation or something along those lines, not only would i see damage to the tops of the pistons, but each individual piston wouldnt have broke in such a replicated manner. since all the pistons broke in the same spot (even on the same side of the piston) i think its a bad batch of pistons. what improper machine work or installation could have caused it? ill take some pics of the cylinder walls tomorrow, but there is no visual damage. i can still see the cross hatch even.

 

ttt. mailing them out in the morning

 

you sending them back to CP for analysis?

 

yeah. i doubt anything will come from it, but at least they want to check them out