Help: lbz cracked piston?

ripmf666

Active member
Sep 20, 2006
15,123
14
38
47
Wentzville Mo
I would stick a set of rods and pistons in it, Key the crank and cam and oil pump,once you get the motor out to see what all went bad see what work needs done to the block.
 

mb1

Member
Nov 15, 2009
149
0
16
Edmonton, Alberta
Is there anyway to prevent this or keep it from happening?

Stock tuning, maybe. There have still been cases even then. Certainly running a tune that will get you to a 12.90 is on the risky end of the spectrum. ( Not hatin' , I'm doing the same )



Aside from needing pistons, how much other damage is normally done from the cracked slug?
 

Leadfoot

Needs Bigger Tires!
Dec 27, 2006
904
31
28
48
Western MA
www.matpa.org
Aside from needing pistons, how much other damage is normally done from the cracked slug?

The biggest concern with a cracked slug is scratching/scoring the cylinder wall.

I have a set of 8 standard LBZ pistons if mine go, but I'm worried about scoring the wall and having to overbore.

Those that have cracked a piston in an LBZ, what kind of damage was done to the wall (able to be honed out or did you have to bore)? If you had to bore, how much?
 

SHOTZY

<"Whats next??"
Aug 27, 2008
474
0
0
melbourne, fl
I cracked mine in my lly and was able to hone with no problem. Coasted for about a mile to the house after it happened. Was very lucky. How long did you run it for after it went?
 

wdino73

Member
Sep 25, 2009
735
0
16
55
Versailles, Ky
Have u seen the piston yet?? I know on mine it had a nice little hole about 6 o;clock, an the crack started thier, I was doing some bad stuff when I melted mine, I'm a bad boy. LOL
I'll try to get so pics up tomorrow I forgot all about posting that, sorry guys, I'll post theim in this thread unless someone objects.
 

dwax

New member
Jul 21, 2009
127
0
0
ill take some pictures as soon as i get mine back together. hopefully my jug is not scored up at all
 

dwax

New member
Jul 21, 2009
127
0
0
i wanted to confirm a cracked started by taking the #4 glow plug out, running the engine and checking for blowby. Well it still has blowby! i guess i need a compression tester