273 adjustable rocker conundrum..

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Thanks Bewy, I'll see about getting a jam nut locally and giving it a try.
Thanks.
Keep us posted on what you find out. On the 273 rockers I did, the interference was all in the rockers. You know how Chrysler is. They dang well may not have been all the same. LOL
 
Keep us posted on what you find out. On the 273 rockers I did, the interference was all in the rockers. You know how Chrysler is. They dang well may not have been all the same. LOL
It can't be cheaper making a hollow bodied adjusters like that. So my guess is there is a purpose for it and it is that the body of the thread has a slight taper and the hollow allows it to distort and lock in place. I have a set in the basement and will check when I get home.
 
What diameter are your springs? I’ve read using a 1.4-1.43 may help as well. I’ve read that on here somewhere.
 
What diameter are your springs? I’ve read using a 1.4-1.43 may help as well. I’ve read that on here somewhere.
Comp Cams 901 springs are 1.494. A lot of people use them as a strong replacement for stock springs.
 
instead of grinding the bottoms of the rockers, like we've all done. I think using beehive valve springs would be the way to go.
Beehive springs? I saved these numbers from a previous post. They are a general purpose spring and the dimensions should be checked before ordering and installing. Comp Cams Beehive springs and retainers: Springs #26986-16. Retainers: #795-16 123 # seat pressure. 284# open @ .500 lift. (stock 340 springs are 96#/242#)
 
As far as these Crower Springs that were set up by the machine shop they even opted to grind the 273 rockers just a little bit .. I'm surely not going to by all brand new beehive Springs and get them set up correctly just to avoid a small .030 spacing on these 273 rockers. Ain't happenin...
 
As far as these Crower Springs that were set up by the machine shop they even opted to grind the 273 rockers just a little bit .. I'm surely not going to by all brand new beehive Springs and get them set up correctly just to avoid a small .030 spacing on these 273 rockers. Ain't happenin...
Grind some clearance then. (even though the "experts" say it shouldn't be done) Those springs will move around some and even with clearance you may get some contact and a tick. Hey they are solids. They are supposed to make noise.
 
Beehive springs? I saved these numbers from a previous post. They are a general purpose spring and the dimensions should be checked before ordering and installing. Comp Cams Beehive springs and retainers: Springs #26986-16. Retainers: #795-16 123 # seat pressure. 284# open @ .500 lift. (stock 340 springs are 96#/242#)
And there you have it $230 for new springs?.. the springs that I have and actually the entire heads couldn't have two or $3,000 miles on them. It would be a good idea if this is where I was going to start but that's not the case...
 
Grind some clearance then. (even though the "experts" say it shouldn't be done) Those springs will move around some and even with clearance you may get some contact and a tick. Hey they are solids. They are supposed to make noise.
The expert in my life is the guy that owns the machine shop that that does the machine work on my engine and my customers engines... He ground the last set I had to Clarence these Springs and again I foolishly sold that set when I got some Hughes rockers for the Duster...
 
And there you have it $230 for new springs?.. the springs that I have and actually the entire heads couldn't have two or $3,000 miles on them. It would be a good idea if this is where I was going to start but that's not the case...
Just passing on some information
 
I first met him on an high School auto shop field trip and he's still doing it...
 
I do have an extra set of 273 adjusters from the first set I had and that's what I was actually doing at first before I found out the crane ones would fit. And I was going through them and it did seem to make a difference when I changed the adjusters.. from one side it seemed four of them I could almost not even turn them and then the other four so I grabbed some of my old adjusters and we're trying some and some spun in and some were much tighter and I left those ones in... Of course I stopped that process when I finally took one out of the crane rocker and screwed it into the 273 rocker and that's what I'm going to end up doing...
So today after I take care of some home stuff I'm going to resort all my rockers face the front of all the 273 rockers face the tops of the adjuster pad clean them all up put them on each side and space them with shims so they only have about 20 to .015 clearance side to side put these rockers on put the push rods in adjust them all and call it a day.
 
As far as these Crower Springs that were set up by the machine shop they even opted to grind the 273 rockers just a little bit .. I'm surely not going to by all brand new beehive Springs and get them set up correctly just to avoid a small .030 spacing on these 273 rockers. Ain't happenin...
No way would I do that either. Beehive sprAngs are overpriced anyway.
 
No need for bee hives.. I done ground them to fit.. And put the lock nut surface against the flat side of my bench grinder.. Done, done, and done...
Kewl. You know how much we like pictures. lol
 
I know and you know how much I post pictures too but right now all you're going to see is them submerged in a coffee can of purple Power...
Hell yeah. I like clean parts!
 
I got looking at my factory rocker arm setup. Curious to see where the "interference" is.
The adjuster took some pretty good effort to remove from the rockers.
I ran a tap down the threads of the rocker and I could almost do it by hand, minimal effort.
I spun(or tried to) a 3/8 NF nut on the adjuster, i got about 3 threads on and she tightened right up.
I reinstalled the adjuster and it threaded into the rocker, fairly easily. Still took some effort a socket and ratchet. But definitely easier after gently running the tap.
So I'm thinking the interference is possibly in both rocker and adjuster?
Trying to find a good grade jam nut locally is proving difficult.
I found grade 2 for 0.25 each lol.

20211026_124715.jpg


20211026_124808.jpg
 
I got looking at my factory rocker arm setup. Curious to see where the "interference" is.
The adjuster took some pretty good effort to remove from the rockers.
I ran a tap down the threads of the rocker and I could almost do it by hand, minimal effort.
I spun(or tried to) a 3/8 NF nut on the adjuster, i got about 3 threads on and she tightened right up.
I reinstalled the adjuster and it threaded into the rocker, fairly easily. Still took some effort a socket and ratchet. But definitely easier after gently running the tap.
So I'm thinking the interference is possibly in both rocker and adjuster?
Trying to find a good grade jam nut locally is proving difficult.
I found grade 2 for 0.25 each lol.

View attachment 1715811538

View attachment 1715811539
My adjuster nuts from the crane rockers were about half that thickness if that...
Almost like if you could slice that nut in half you'd get two... I have to agree I was finding that of my rockers would unthread and thread in easy or very hard and then I could just change the adjuster and it would thread in a lot stiffer and one that I pulled one out of easily..
 
My adjuster nuts from the crane rockers were about half that thickness if that...
Almost like if you could slice that nut in half you'd get two... I have to agree I was finding that of my rockers would unthread and thread in easy or very hard and then I could just change the adjuster and it would thread in a lot stiffer and one that I pulled one out of easily..
Those don't look like adjuster nuts but just regular nuts.
 
I got looking at my factory rocker arm setup. Curious to see where the "interference" is.
The adjuster took some pretty good effort to remove from the rockers.
I ran a tap down the threads of the rocker and I could almost do it by hand, minimal effort.
I spun(or tried to) a 3/8 NF nut on the adjuster, i got about 3 threads on and she tightened right up.
I reinstalled the adjuster and it threaded into the rocker, fairly easily. Still took some effort a socket and ratchet. But definitely easier after gently running the tap.
So I'm thinking the interference is possibly in both rocker and adjuster?
Trying to find a good grade jam nut locally is proving difficult.
I found grade 2 for 0.25 each lol.

View attachment 1715811538

View attachment 1715811539
That's how my slant 6 rockers are. No interference in the rockers. I was able to just screw the Crane adjusters right in.
 
Couple of observations.
- might be the pic, but the adjuster ball looks quite pitted from corrosion.
- with the thick nut, very little wriggle room left for adjustment.
- top of the p'rod cup might contact the rocker at max lobe lift.
 
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