I don't know, but to me it sort of looks like they were hit with a wire wheel, not refaced. Those worn rocker tips are a good example of why using a flat feeler gauge to adjust the valve lash often provides innaccurate or inconsistent results. On the heads I rebuilt the rocker tips weren't so bad as those, but the rocker bores and rocker shafts were trashed, heavily scored and galled in spots due to poor oiling "back in the day". This is unfortunately common with as-found Y Blocks today. Were it me and I had to use them, reface them keeping the same radius.

Maybe you know this already, there is a place out in California that rebuilds them, Rocker Arm Specialties. The clearance between bores and shaft is spec'd @ 0.002" - 0.004" wear limit 0.007" ; this affects overall oil pressure.

I have a streak of stubbornness coupled with a dislike of re-installing defective parts. It takes just as much effort to remove, disassemble, clean everything up, reassemble and adjust everything with worn out parts as it does with new or serviceable parts so whenever possible I like to use new parts and make sure everything is according to Hoyle.

I found for example upon inspection just about every single pushrod was actually slightly bent or had excessive runout + the worn rockers and shafts. Slop and excess clearances in each valve have to be taken up first before that valve will begin to move. Too, everything slopping around means the valve rocker will never hit the same spot on the valve stem twice in row or have the same valve timing/lash. Depends on how picky you want to be and how much $$ you want to contribute to feeding your OCD like me.

OK here's a couple pics.   All these rockers shown were on the same shaft.  The shaft is new,  was part of a never fired rebuilt 312.  The rockers aren't rebushed,  maybe they were honed a little.   No looseness or wobble on the shaft on any of them.    I know Tim McMaster has a video of rebuilding rocker arms where he grinds them.   Don't know if he has a limit where he considers them junk.  

Can you post a pic or two, representative of the rocker tips that still have them? Interesting question. The next question is, what did they do to address the rocker bore wear, honing or sleeving?

Had to hunt around a bit and buy them in onesies and fivesies etc., but was able to put together a complete set of NOS stock ratio 6564 rockers for an average of $5 - $7 per delivered.

I was asking  because if I can dress the rockers myself,  I would.   I have a friend who has a Black and Decker valve grinder that he says I can play with.   There is a rocker grinding attachment for $95 on Ebay.   If I had the dimensions I could make it myself.   That way I could get rid of the divots in those rockers that still have them.   I just wonder how much can come off before you weaken them to unusable.

The concern by Ford likely centers around the finish, the radius, and the depth of the grinding performed by people not really trained to do that.  And then down the road at a later date, ‘regrinding’ again which simply reduces even more depth and possibly getting into softer material.  If I was a dealership back in the day, I’d definitely be putting new rockers on rather than refurbishing.  As you mention, refurbishing rockers is now a way of life now that the engines have been out of production for a half a century.

Lorena, Texas (South of Waco)

Have the rocker bores on those been rebushed, or honed? I think that's the important part. Many Y blocks were run without adequate oiling up there and the rocker bores and shafts exhibit heavy galling and scoring on the underside. I wouldn't worry too much about the rest of it.

Although, for whatever it's worth - the Ford shop manual says

"If the pad at the end of the rocker arm has a grooved radius, replace the rocker arm. Do not attempt to true the surface by grinding." (emphasis theirs)

Wonder why they had their panties all in a wad about this? If maintaining the proper radius is a concern, there are rocker grinders that do just that. Done all the time. Surface hardening only so deep? Maybe, but Y rockers in general are getting a little tough to find and/or spendy when you can get them.

Don't know about a grinding limit, but it sounds like someone maybe ground the ones U have just enough to allow a feeler guage to work properly...


Paul

I didn't want to start a new thread cause  I have a question about rocker arms.   I'm going through my arms,  and I have a set that are on new shafts and have supposedly been reworked.  However,  about half of them still have wear spots from the valve tips still showing.   You can see they've been ground on,  but not enough to remove the spots.   Is there a limit of how much material you can remove?    They are on new shafts and don't have any sloppiness on the shaft part.   

N.B.- I was going to enquire of Rocker Arms Unlimited re Y-Blk valve train parts or rebuilt units etc.. However, noticed they are in Redding Calif. This is likely not a good time to bother them with enquirys, due to the terrible fire situation in that area...  I hope all is well with them & anyone else on this site that might be from that area.. Best wishes!.. 


Paul

Marc - still have them - sent you an email


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