picked up 4 new rockers at clasic frome german ford v6,they had 7/16 size screw,ued the screw on y rockers and they wher tight  but worked. anoying when adjusting with 2 sizes to deal with. rockers them selves had smaller shaft

picked up 4 new rockers at clasic frome german ford v6,they had 7/16 size screw,ued the screw on y rockers and they wher tight  but worked. anoying when adjusting with 2 sizes to deal with. rockers them selves had smaller shaft

Daniel, as I understand it the adjusters with the smaller head are the ones with the slightly over sized threads. Don't quote me though - check it out.


Mark

1956 Mercury M100
1955 Ford Fairlane Club Sedan
Delta, British Columbia

I recently rebuilt a set of ECG 6564 rocker arm assemblies like you and put on new shafts, etc. When I started the process, there was a mismatch of adjusters... actually 3. The original lock nut style (I really believe that all ECG assemblies came from the factory that way... at least the ones I have seen). Someone had replaced 5 of the lock nuts with interference fit adjusters - why I have no idea. But they were so tight I had to literally use a vise and a breaker bar on each individual rocker. A better idea would have been to heat them up but I was in a hurry so I didn't want to get the torch out, etc. I replaced those interference fit with lock nut adjusters, and we are all good. I personally prefer the lock nut adjuster over the interference.
The oddity was that there were two different heads on the interference adjusters - one was 1/2 and the other 7/16... don't know what all of that was about - could have been an aftermarket anyway, but what a pain in the keister for the guy trying to adjust the rockers with those things all installed, you would need half your toolbox!!

Daniel Jessup

Lancaster, California

aka "The Hot Rod Reverend"
check out the 1955 Ford Fairlane build at www.hotrodreverend.com

Here are a couple of past threads regarding the ‘interference fit’ threads on the ’57 and up rockers.
http://forums.y-blocksforever.com/FindPost107602.aspx
http://forums.y-blocksforever.com/FindPost98395.aspx

Lorena, Texas (South of Waco)

New adjusters with lock nuts from J Mummert have an internal hex to suit an allen key.
I guess that would save a little weight. 

South Australia

PF - yes.  Ford continually made changes to their product through its run.  The rockers I have are about half and half.  According to Ted, there's no penalty for running the heavier locknut type adjusters, so if you've the pieces to make it work - go for it!  

Chuck & Brodie: So, if I understand your posts, some ECGs came originally with screw & Lock nut style adjusters? ( Eickman's book just says the later style was introduced in 1956.) That likely explains why they are overly tight, as someone switched from the early style adjusters, that's likely why they showed up at a swap meet...  I have no suitable tap or knowledge of what that thread is, so to try running a tap in to them is likely out. I  don't think heating them is the answer in this case either, because when they cooled they would still be almost impossible to work with. When I said they are tight, they are very tight! I do have another set of rockers here to disassemble & work with. - Thanks      


Paul

I have a spare set of old style rocker arm adjusters with locknuts if you're interested.  I've had both styles of adjusters in the 1.54 rockers, my assumption this is the locknut is a '56 item where the interference fit is a 57 & up.  

The interference fit appears to have been accomplished by broaching the adjuster die.  This would have cut the apex off the thread of the die, resulting in a shallower root on the adjuster thread.  If the adjuster is going into a rocker that never had an interference fit unit, the adjuster will have to move some metal on the rocker on the way in.  I'd use some light machine oil while threading to prevent galling.  

Another "trick" is to put the rockers (but not the adjusters) in the oven at 400 degrees F for about a half hour.  Adjusters will go in more easily when the rockers are warm.  

Hope this helps you a bit.  

Paul:
I have the 1.54 rockers with the jam nuts, so they were available.