Cracked LML pistons

[PureHybrid]

I agree with you Caleb, but I have a question: have you seen significant damage caused by prolonged run time of a cast piston which was starved of oil supply due to a broken squirter?

Major damage. Depends on the heat you put to it, and where it broke. Piston will scuff, maybe melt with enough heat. If the tip bends or breaks you may not notice for a while or not at all if its driven easy, but if the banjo bolt itself breaks you'll see a drop in oil pressure.

 

[juddski88]

But it may not drop below a dangerous level (20psi or so) as we had a lb7 this year that had a broken one for anywhere between 1 - 4800 miles at nearly 600hp. No piston or cylinder damage done.

 

[PureHybrid]

Where and how did it break? Was the truck daily driven or a tow rig? Under sustained temps during towing it will scuff in a hurry.

 

[juddski88]

Street driven and pulled and dynoed. Mileage was put on in approx. 4 months. It broke at the soldered joint of the fitting in cyl 1 at an unknown time, but presumably immediately after it was originally assembled. No noticeable drop in oil pressure by owner.