dead cylinder ?

[PatAllen]

found this on a early stamped 69' engine assembly i kept "just in case".

on a 121 head with the small valves....

never saw one burned this far....

the seat is gone as well.

[Simeon]

Crack first and then burn? Something passed through it?

[Guest_anonymous]

"Just in case" of..............aluminum prices rising drastically? 

[Mike Self]

My Feb '69 02 had the seating surface on one of the intake valves wear completely away, allowing the valve to pull up into the intake tract, breaking a rocker arm.  This happened at just shy of 100k miles.  When we pulled the head, all three remaining valves were nearly worn through; one was so sharp on the edge that it would cut paper.  

 

I was told by the machinist that re-worked the head (no damage to the seats, surprisingly) that it must have been a batch of badly heat-treated valves.  Haven't heard of that problem in any other 2002.

 

mike

Edited January 9, 2017 by mike

[TobyB]

I have just one word for the PO:  SHIIIFFFFFTTTTT!!!

 

My dad makes valves like this.  He lets the engine rev out to the stratospheric heights of 2200 rpm,

then shifts.  And sometimes shifts again, just to be sure.  In his defense, he was a history teacher,

so I learned everything I know (about the Civil War) from him...

 

He has this theory that "it's a truck" so it shouldn't rev.  Even though it's an Isuzu mini- truck,

and redlines at 6000.  And makes max TORQUE at 3500.

 

So I'd guess that valve came from lugging the engine- too low revs for too much throttle.

 

He did it to his full- size 4.6l Chevy, too...

 

heh

 

t

 

[ray_]

Taxi drivers in China shift like that also. Drove me nuts!

 

[02Les]

1 hour ago, ray_ said:

Taxi drivers in China shift like that also. Drove me nuts!

 

Yeah, they were in 5th gear at 20mph....AND...the car still pulled away!

[ray_]

15 minutes ago, 02Les said:

Yeah, they were in 5th gear at 20mph....AND...the car still pulled away!

Relative to bicyclists!

 

[PatAllen]

i went one time to Taiwan. i was in a cab and i felt like i was into the Matrix movie as all the scooters and bycciles passed us by, in all directions....lol....