Just thinking out loud,, I'm not sure if the new set of tubes I got in November of last year are the shorter ones, but if they are Not,, Wouldn't the shorter ones be a restriction by not allowing the valves to open all the way? Not sure if .05 is enough to change anything. It'd suk to have even higher egt's with them. I guess I could defuel to compensate, but that sux also. Thoughts???

 

ARE you thinking the wrong push tube caused this trouble with the Cam

 

Long or short you should still be getting the same lift. The problem
with the longer ones is bottoming out the lifter.
There is a lot out there about hydraulic roller lifters and not everyone agrees
Roller Lifter Install - Solid Roller Power From Hydraulic Lifters - Car Craft Magazine

Here is the google search"bottoming out hydraulic lifter"

So it can go both ways depending on what you read.
Also without knowing just what condition the engine is in and what
the failure was we can only guess. My money is still on the thrust
bearing going south.

Sean

 

MY speculation on the shorter pushrods is that Ford is repairing and reusing a LOT of head cores that won't meet the specified deck height of 3.74" and they're forced to use shorter pushrods to compensate. I've also heard speculation that it's to take pressure off the lifters. The new pushrods are the same in the 6.4 engines.

 

I'm not following how the valve travel would not be affected by shorter pushrods. How would the valves travel the same distance if the tubes are shorter? Wouldn't this just mean the rockers have less tension for longer? I'm no physics major,, obviously. Lol. But I know when the valve train is not on the high side of the lobe,, I can wiggle the rocker. My heads have never been decked either. I know the lifters have some spring in the tube seat. But I'm questioning if that spring travel is used on the high side of the lobe.

 

I just thought if the Pushrod was too Long it would eat into his Cam like it did


But if he had Shorts then shouldn't eat the Cam plus it wasn't Decked

With SHorts Pushtube would be Shorter Duration Im with Ya Anothony

 

The hydraulic part of the lifter is what makes up the difference.
Here is a little Youtube video I found
This is the test that the person put up that is hidden till you hit the show more.

Uploaded on Feb 3, 2008
The internal work of the hydraulic valve lifters, commonly found on lots of cars and some motorcycles too. the idea behind this is that LIQUIDS CAN NOT BE COMPRESSED.

While some valve systems use screw-and-lock-nut OR shims (metal plates in different sizes) to adjust their valve clearances, engines with hydraulic valves do not need periodic valve adjusting.

This is how it works:
engine oil is pumped constantly by an oil pump, enters through the one-way entrance (where the green ball seats) into the chamber. The oil is then trapped in this chamber and acts as a solid (that can't be compressed remember?)- and by that eliminates any clearances in a chain of moving parts (between the cam lobe and the VALVE head).

Now in case of wear, there is a chance that when the engine is stalled, the oil pressure in this chamber will drop drastically, and that is why when you start such an engine once again, you will notice a ticking noise for a short while, maybe couple of seconds. Noise is clearances, and the noise stops as soon as the oil pump will push enough oil to fill the tappet chamber again.
In a good engine, pump keeps feeding the system oil, always equal the volume of oil leaking out of the system (of natural clearances between the parts, wear, etc)

The pros of this system is that it rarely needs maintenance and an engine that has such a system will need no periodic valve adjusting . In motorcycles most Harleys have hydraulic valves, and some KAWASAKI cruisers too.

The cons of the system is that a contamination (little metal part that the oil filter didn't catch, etc) can cause the hydraulic tappet to leak oil from the chamber , allowing it to be susceptible to squeezing = therefore not closing clearances = therefore causing valve system to make rattle/ticking noises. Repair then, is relatively complicated. This can happen in old engines where the wear is too much and the parts shown here (tappet lifter, plunger, body) cant hold enough oil, that leaks from the sides (where ever it can).

You can see a more clear flash version of this in:
Hydraulic disk brake system « motoetc.com – Online Magazine for Motorcyclists, Scooterists and Technologists....

All credits go to Youtube user Golbis for posting this.

Sean