All aluminum FE hydraulic roller lifter adjustment

[Tommy-T]

Working on a Pond aluminum block with Carroll Shelby heads. Also has Erson roller rocker arms.

Not sure of the lifter manufacturer. They appear to be short travel, but can't really tell. You cannot push down the plunger by hand, and if you take out the circlip you need a bench vise to get the plunger back in to install the said clip.

So what is the correct adjustment for lash on initial (and after initial) start-up?

[blykins]

If they are short travel, you’ll want to almost bottom them out at initial as an all-aluminum setup will lose about .014” of preload or gain about .014” of lash as it gets hot.

Most short travels have about .030” of travel.  So if you get them close to bottom of travel cold, they will end up at mid travel when hot. 

You can measure the adjuster threads on your Ersons.  Seems like most rockers have about .050” per turn.  You could aim for zero lash plus a 1/4 turn when hot.

[CaptCobrajet]

I would take the slack out so that you can roll the pushrod, but no depression of the plunger yet.  Then, figure out your threads per inch and turn it down a full .030 from the zero preload point.  The all-aluminium engine will grow a bunch between being cold on the stand and heat soaked operating temps.  You don't want it to thrash when hot.......that is how I approach what you describe.  If they are not short travel, I would peload .065 to .070 in all aluminum.  You really need to get the oil out of one and see how much movement you really have.

[McGaviR]

We have a very similar setup. The advise provided in the earlier replies by the FE engine builder gurus is inline with what we did when freshly built. The challenge/frustration we find is after the first start, the lifters don’t bleed down, so where to set them then? Our approach has been to remove any lash when cold and then screw the adjuster down 1/4 turn. We occasionally get one or two that are a bit noisy so we nip those ones down a whisker more. Any more than this we were finding valves were hanging open when cold.