There is nothing wrong with the original pushrod length. Those were also installed in the early 6.4L engines, and that's where the problem showed up with the engine design change. Then, International shortened the pushrods, and Ford inventoried only the shorter pushrods to ensure no 6.4L repair would encounter an issue. This comes from Geoff at Colt Cams, who also noted a problem with the ramp of the lobes in one of the 6.0L cam designs.

I used the TA-31 sealer with all my cord gaskets on the outer side. If this is coming from the rocker/head connection, you could clean the outside surface thoroughly and use TA-31 on the connection to help prevent seepage. Not pretty, but you could use masking tape to produce a straight edge parallel to the connection so it looks like a band, rather than a backyard smear. TA-31 is known for its tenacity in tightly bonding to surfaces.

Stronger pushrods may be needed if you are using valve springs rated for higher-than-stock spring rates at higher rpms. But pushrods are the fusable link in the valvetrain system. When things go bad, you want them to bend. You don't want the rockers to break or the lifter roller and cam lobe to get damaged.

 

Jack, do you have more detailed information about the push rod lengths? I always install Johnson lifters with shorter rods. However, these vary between 248.5 and 246.5 mm. They are the same length in the set, but vary from delivery to delivery.

 

Ever since replacing the heads my engine has had a subtle ticking at idle that wasn't there before. What I have read is that the "updated" push rods are 0.0055" shorter. It seems possible I could have removed that much from the decks. That's one measurement I didn't check.

I also made the rookie mistake of lubing the threads at the bottom of the studs going into the block. I never saw any discussion about that until after I was finished.

These are the things that keep me up at night, and only one way to correct them, unfortunately. Now with this oil leak, it's one more thing pushing me into pulling the heads. Somehow I knew I was going to be doing it all over again.

 

ARP recommends lubricating those in that area, so I wouldn't call it a mistake. I think Hartwig and I take a different thought path.

You can always re-torque the studs, even if it means not backing any off but going to the stated value. With the ARP lube, there should not be a significant static friction issue. I plan on retorquing mine, as fasteners and gaskets do relax. I've also marked my studs and nuts to the forward position so I can visually tell if they have backed off. You can still do that, at least to the ones visible.

Jared (KDD) early on noted on PS.org that he observed a variation in the early rockers, which would explain why International went deeper into the lifters' plunger depth than normal practice. There is nothing wrong with that, but I understand your concern about different valve recessions and block/head thicknesses.

 

It's been three weeks since I cleaned-up the oil and it still looks clean and dry. There must be something about the open to atmosphere CCV delete with 1" hose that it doesn't like. Which doesn't make sense, because when I had the Parker 4500 filter on it, there wasn't very much oil in the cup, even after ten thousand miles, which suggests there isn't that much blow-by.

 

Spoke too soon. The dripping has started again.

I just may pull the engine if I have to redo the heads, and seal up the lower end and replace the back lifters.