PDA

View Full Version : Cracked Piston



Hansh
05-24-2005, 18:29
Took off the head today on my 93 6.5TD, and found a cracked piston at the #2 cylinder. What would cause this? Cracked about 3/4 way across middle of piston. New IP - approx 8000 miles, and new glow plugs, approx 3000 miles. Thanks for the help.

Hans

rjschoolcraft
05-24-2005, 19:30
Mine had three cracked pistons. These engines are known to run extremely high egt in stock form. Gages are a must. High egt will thermally weaken the aluminum pistons allowing stress cracks to form and popagate in fatigue.

See this thread (http://forum.thedieselpage.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=1;t=007942) to see photos of mine. Some blame it on high boost pressure that I was running, but I've seen too many stock engines crack pistons. Heat, in the form of high egt, is the culprit.

Cowracer
05-25-2005, 09:46
Welcome to the cracked piston club! RJ and I both have suffered and we both agree that EGT's probably did the damage a long time before the thing actual grenaded.

My story click here. (http://forum.thedieselpage.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=1;t=008561) Pay particular attention to the last paragraph. Learn from my mistake!

Tim

84 Convert
05-27-2005, 06:36
I have a 6.2 N/A that had carcked some pistons, 6 of them to be exact. I'm sure it was from high EGT's only having a single 3" exhaust, heavy towing and bad head gaskets ( water temp over 220*)! I now have a new pyrometer to keep an eye on things but I'll pobably have the turbo installed before I tow with it again.

HEAT KILLS

Gregg