Pushrod oiling/heat?

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The problems with shims more than about 0.010" thick is that for there to be no leakage, they need to be an elliptical shape, [ thinner on the ends, thicker in the middle ] to close up the gap under the shaft. That is why the pedestals crack when parallel shims get used: the ends of the pedestals are getting 'spread' & then spreading as the bolt tightens & tries to seat the shaft in the pedestal.
I did it a better way. I made my own 0.020" shims, which I siliconed to the pedestal & left overnight to cure; so this stops the oil leakage from that gap. I do not use bolts. I use s/steel studs, loctited into the pedestal. A nut is then used to 'snug' the shaft down into the pedestal; another nut is then used to lock against the first nut to prevent loosening.
 
Get in touch with Mike @B3RE and he can solve all of your problems. I tagged him so hopefully he'll chime in.
 
RustyRatRod said:
Get in touch with Mike @B3RE and he can solve all of your problems. I tagged him so hopefully he'll chime in.
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I was actually in contact with him prior to buying the problem shims......lesson learned it was the tail end of the build I was trying to be frugal and it bit me in the ***. I'm just glad nothing major happened yet and I have time to correct the mistake.
 
Bewy said:
The problems with shims more than about 0.010" thick is that for there to be no leakage, they need to be an elliptical shape, [ thinner on the ends, thicker in the middle ] to close up the gap under the shaft.
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I don't think that I'm giving away any secret by saying that the way to achieve the proper shim shape is to have the same radius on the inside and outside. That radius should be whatever the radius of the rocker shaft is. The tapered ends happen automatically. Stack two washers of same diameter on top of each other and offset them .020" and it becomes obvious. Creating that profile in the shim would require a milling machine or lathe and a bit of machining knowledge. Shims made this way would theoretically seal as well as if they aren't there because all the radii match.
 
Hallzy said:
I was actually in contact with him prior to buying the problem shims......lesson learned it was the tail end of the build I was trying to be frugal and it bit me in the ***. I'm just glad nothing major happened yet and I have time to correct the mistake.
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As Gomer Pyle would say, "shame shame shame".:poke:
 
Hallzy said:
I was actually in contact with him prior to buying the problem shims......lesson learned it was the tail end of the build I was trying to be frugal and it bit me in the ***. I'm just glad nothing major happened yet and I have time to correct the mistake.
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IF you follow EXACTLY what he says do, he will fix you up. He did me.
 
gzig5 said:
I don't think that I'm giving away any secret by saying that the way to achieve the proper shim shape is to have the same radius on the inside and outside. That radius should be whatever the radius of the rocker shaft is. The tapered ends happen automatically. Stack two washers of same diameter on top of each other and offset them .020" and it becomes obvious. Creating that profile in the shim would require a milling machine or lathe and a bit of machining knowledge. Shims made this way would theoretically seal as well as if they aren't there because all the radii match.
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Well no, most times, the shims need to be thicker on one side to allow relocation of the rocker shaft in order to get the correct rocker sweep on the valve tip correcting for the poor Chrysler valve train geometry. That SHOULD BE the only reason for placing any shim under the rocker shaft.
 
gzig5 said:
I don't think that I'm giving away any secret by saying that the way to achieve the proper shim shape is to have the same radius on the inside and outside. That radius should be whatever the radius of the rocker shaft is. The tapered ends happen automatically. Stack two washers of same diameter on top of each other and offset them .020" and it becomes obvious. Creating that profile in the shim would require a milling machine or lathe and a bit of machining knowledge. Shims made this way would theoretically seal as well as if they aren't there because all the radii match.
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Exactly! This is why we have made the correction kits with billet bars that are machined for the correct radii, inside and outside, from the very beginning. I've seen the damage a flat shim can do. Also, a .030"ish shim isn't doing enough for true geometry to make any real difference. With an Edelbrock head, I'm thinking it will require 5 times that much, or more.
 
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RustyRatRod said:
Well no, most times, the shims need to be thicker on one side to allow relocation of the rocker shaft in order to get the correct rocker sweep on the valve tip correcting for the poor Chrysler valve train geometry. That SHOULD BE the only reason for placing any shim under the rocker shaft.
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Technically, if it isn't flat, it is no longer a shim. It is a spacer. Shim material is flat by definition. A tapered "shim" is a wedge. Exactly what you don't want exerting pressure on a rocker stand.
 
RustyRatRod said:
Well no, most times, the shims need to be thicker on one side to allow relocation of the rocker shaft in order to get the correct rocker sweep on the valve tip correcting for the poor Chrysler valve train geometry. That SHOULD BE the only reason for placing any shim under the rocker shaft.
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I wasn't trying to address the geometry correction or the math associated with it. I'll leave that to Mike. Simply pointing out how to make the shims. If they need to have an offset, that adds a little bit of complication and maybe is easiest to accomplish in the mill.
 
gzig5 said:
I wasn't trying to address the geometry correction or the math associated with it. I'll leave that to Mike. Simply pointing out how to make the shims. If they need to have an offset, that adds a little bit of complication and maybe is easiest to accomplish in the mill.
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I understand. Thank you, drive through.
 
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