Dreaded Effing lifter tap...... - SOLVED

[Blackcar]

No. When the lifter is collapsed the distance the pushrod travels is less, there will be no valve to piston contact.
I did a lot of research when my lifter collapsed.
It is the geometry of the pushrods and placement of rocker arms above the valves. They do no push strait up and down like an old small block but instead have a pronounced angle that works 'fine' until a lifer collapses. The gap created from the collapsed lifter causes the pushrod to bend in very short order.

A view on valve train.

 

[B-train]

Great video!

A view on valve train.

Great video! Who would've known. Thanks for sharing

 

[B-train]

Well, update as of 10/19. Got the truck back and it runs as good as new. In going over the situation with my dad (master mechanic) he basically said it was most likely cause by a heavy right foot. In thinking back on the situation, my foot was heavy immediately after the situation, getting irrate at a stupid Jay walker and trying to get out of traffic. A floated valve can do the same thing.......so, it may not have happened right then, but driving several hundred miles on a fatigued pushrod could have showed up later. Or....a ******* porter kid drove it hard at the shop.

All speculation at this point, but it makes sense to me. $650 later for diagnosis, repair, and oil change and we're back running. Drives like new!

We'll give it some time and see. All emotions have settled down by now, cooler heads have prevailed, and no rash money dumping situations have happened. What it has shown is that we were used to having a spare yukon available for the 'what if' situations due to me having a company truck all these years. Now, the 'spare' is a DD. We'll probably solve then issue with a good used, mostly depreciated, rust free 3rd vehicle to use as needed - also something that gets much better mpg for all the bee-bopping that goes on in my household.

At this point, it's nice to have it back in the fleet. I'll keep the thread updated if something else changes.

Thanks to all the insights and replies!