rocker arm self locking:in the 1980's ford had a V-6 engine that they put in Ranger pickups it used adjustable rocker arms
  with self locking screws that are the very same as the screws used in y-blocks and solid lifter fe ford engines.Found this
   out by accident. Happy hunting.

     john2747

Seems to be some confusion on this inquiry. (??)  Anyway, a side note. If the requested one piece adjusters are to be used in earlier rockers by chance, the thread is different, they won't work in original 2 piece adjuster rockers.. 

P.S.- apparently I'm informed that'information is incorrect..


Paul

I have to disagree with that statement.  I had to use a one piece in place of a two piece and had no problems with it.  Did it about five years ago.  The only thing about it is that there is very little adjustment left once you got to the .019 position.  I just changed it this spring as I got a two piece adjuster.





54 Victoria 312;  48 Ford Conv 302, 56 Bird 312
Forever Ford
Midland Park, NJ

My experience is like Paul's. I put a new shaft in one side of my engine and used the best of several rocker arms I had. I put the two piece adjuster in an arm that had the one piece adjuster in it and the threads felt perfect.

O.K. I may stand to be corrected..  But lets look at this again. Gene says he put a 2 pce adjuster into a rocker arm intended for a one pce & it was o.k. I  was referring to the opposite, so can't comment on that working o.k or not.  Paul says he did it the other way & it worked o.k.. That surprises me because the thread is an interference type on the ECG-xxxx B2, 1957 rockers. Now, is the interferience thread built into the arm or the adjuster.? .. Anyway, I'm really scratching my head now, because in issue #143 of Y-Block Magazine, there's an article c/w photos of the different rockers used on Y-blks. You've got me reviewing this subject. Obviously I didn't read it thoughly enough, because I've got a set of rockers here that are ECG-xxxx B2, which are the 1957- 1:1.54 rockers with one pce adjusters. I mistook them for 1956 rockers, (which are suffix A1) & I thought someone had used one piece adjusters in earlier rockers, because none of the adjusters work properly. With a 10" spanner. I can barely if at all turn the adjuster on most of them. Now, I'm I'm thinking they may be adjusted to far down, or rusted in the threads or someone may have put thread locker on them.?  Looking into it tommorrow. - Thanks       


Paul

Paul, I know what you mean about some of the one piece adjusters being hard to turn. When I discovered one side of my rocker assy had a worn shaft and rocker arms, I dug an old set out of the attic to see what i could salvage. The attic rockers had pretty good bores, but had hard crud in the little oiling holes for the push rods and the valve stem oiling. I elected to take the one piece adjusters out for access to the oiling holes. Some of them were really hard to remove. When some of them were put back in they were noticeably less tight. I'm no expert on these, but I did read somewhere that the interference was in the threads of the adjuster, not the rocker.

Paul & Gene; I've got sidelined re this subject, will get back on it when I can..


Paul

Returning to this subject;  The article on Rocker Arms in Issue 143 of Y-blk magazine by Lindsay Shoemark out of Australia, is quite extensive. It lists 4 types of Ford factory rocker arms & early aftermarket Magnesium ones by  Howard & Thomas. Only 2 factory units are 1:1.54 ratio. All others are 1:1.43 ratio. I was under the impression that the 1:1.54  ECG **** A2 rockers with 2 pce adjusters were from 1956.. but the article doesn't indicate that, so that is a ??.
I thought that someone had tried to convert the ones I have here from two pce to one pce adjusters, but it's been pointed out previously that's not the case. Most of the ones I have here that are near impossible to adjust are the 1957 ECG **** B2 units c/w one pce adjusters. I've taken to soaking them in solvent & then applying penitrating oil. Today with some effort, I was able to remove some of  the adjusters, clean the parts well & get  three of them to work reasonably well. It's a slow process & some of the shaft contact services are too worn to be considered re usuable... It should be noted that old used ones often have one or both oiling orfices plugged with dirt or sludge. It's very important that those oil orfices be clean when reasembled..
Re the Thomas rockers-  Somone on this site or in Y-Blk mag had indicated that they had information that they were prone to failure. Many years ago a buddy of mine bought a set. Used in his Drag car for a short time, yes one did fail, it snapped right in half !.      


Paul

  I would say both answers are correct. Nut locking rocker arm bodies are threaded normal 7/16" NF [20 TPI] .The rocker arms are drilled or reamed to 25/64" [.3906"] before they are threaded.
   Self locking type rocker arm bodies are drilled or reamed to .397" to . 398" before threading 7/16" NF--- yes,they have larger inside diameters.The larger bore dia. creates a larger flat on the top of the internal threads.
   The two piece adjuster screws have normal 7/16" NF 20 TPI threads and can be used on either nut locking or self locking style rocker arm bodies.
   The self locking type adjusters have a normal 7/16" NF 20 TPI threads, for the first two turns.the rest of the adjuster threads have a shallow depth with a wide flat at the bottom of the thread [modified thread] The diameter of the flat bottom is about .400"-.401".When the self locking adjusters are screwed into a rocker arm that was made for them the flats on the tops of the internal threads create interference with the bottom flats of the adjusting screw. So both rocker arm threads and adjuster threads create the tight fit.
   I just measured the inside thread diameters of seven EAN rocker arms one rocker measured .398". I screwed a self locking adjuster into it,and it screwed in fine with 3 ft.lbs. of torque.So if the older nut locking rocker arms [1956] have there bores reamed to .397" they would be converted to use either type of adjusting screw .                                                   
                                          john2747

Interesting..  thanks John.


Paul