Crane Rocker arm clearance on Iron heads issue

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C2ndLTpigeon

C2ndLTpigeon

Mopar or no Car!
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I am mocking up the rocker arms on my 340. I am using a set of Crane 1.5 rocker arms that came with the engine I purchased. I am running a Mechanical solid cam.
My issue is during installation I am noticing that the outer arm on for the number 1 Exhaust is rubbing the shaft mounting tower. This is not allowing the second bolt in to screw in all the way as it there is pressure from the rocker rubbing. This is not an issue on the opposite side head and I have taken this shaft with rockers and swapped it to the other side with no issue. Which is making me believe that this heads casting may be a little bit wider on that tower? Can anyone confirm that this is the issue? If so is it as simple as grinding some of the tower back so that the rocker arm clears?
Here are some pictures.

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Here is the passenger side with no issue, and same shaft swapped but clears fine.
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Try measuring the spacers and swap them around if one is a bit thinner, that may cure the problem.
 
To be clear the shafts were on a set of X heads but now they are on a set 974 360 heads. What puzzles me is that the same shaft that will rub on the number 1 exhaust will not do this if I swap it to the other head. I have checked all the thicknesses on the spacers and rockers and they are all within .001 of each other. I also dont want to kick that one to the right as the roller sit of to the side on that valve.
 
Ricks70Duster340 said:
A ten gallon fuel cell would mean a lot of stops at the gas station!
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C2ndLTpigeon said:
To be clear the shafts were on a set of X heads but now they are on a set 974 360 heads. What puzzles me is that the same shaft that will rub on the number 1 exhaust will not do this if I swap it to the other head. I have checked all the thicknesses on the spacers and rockers and they are all within .001 of each other. I also dont want to kick that one to the right as the roller sit of to the side on that valve.
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Have you measured the width of the standoffs? Those may be wider.

I would call Mike as stated above. He will provide free advice, he is as great resource
 
Ok my Dad said to check the thickness of the inner pedestals and I think they are the culprit. The good side shows' them to be more centered. The side in question the numbers are not so symmetrical.

Good side:
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Side in question:
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The picture with the measurement of 0.319 is the rocker that is rubbing.
So I am coming to the conclusion that all I will need to do is shave a little bit off of that pedestal and I should be good?
 
Could be those spacers in between the rockers too
 
It cannot be the spacers, because the rocker is hitting the shaft pedestal BEFORE it is even lined up with the valve tip. The rocker needs to move TOWARDS the pedestal and nothing you can do with the spacers will help that. Grinding the inside of the pedestal is the way to correct this.
 
Wow, that one hole is offset horrible in my opinion. And like you said you dont want to push rocker to the "outside" as that looks like it's barely hitting valve to begin with....center to center measurements on all the holes?
 
4spdragtop said:
Wow, that one hole is offset horrible in my opinion. And like you said you dont want to push rocker to the "outside" as that looks like it's barely hitting valve to begin with....center to center measurements on all the holes?
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I will have to check tomorrow. But seems like this head was off quite a bit then the other.
 
RustyRatRod said:
It cannot be the spacers, because the rocker is hitting the shaft pedestal BEFORE it is even lined up with the valve tip. The rocker needs to move TOWARDS the pedestal and nothing you can do with the spacers will help that. Grinding the inside of the pedestal is the way to correct this.
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Makes sense. I will check everything once it's bolted down after I grind at the pedestal. The center of the rolers on that cylinder look like they are to the right. I will see if this bumps them to the left a little. Otherwise spacers will be next.
 
Not surprised that you are getting interference. The pedestal is a casting that is not machined to size & can vary in size. It is like core shift. The problem is obvious in post #7 with your caliper measurements.

You need to grind the pedestal for clearance. Do not grind the rocker, that area of the rocker has the most load on it & grinding it will just weaken it for the big bang....
 
Post#9 is the right answer. The casting is interfering with the rocker centering over the valve. Grind the head.
Then you may need to add shim thickness when you're done.
 
Just as an FYI, I would grind enough from the shaft pedestal so that you can add a thin shim between the pedestal and rocker to act as a washer. That pedestal casting is rough and might act as a grinder on the rocker arm over time.
 
You will need to have the stand milled off for Clearance.

One other thing I would like to mention is do not use the cap spacers on the bolts to ride directly on the Aluminum rocker . Place hardened shims on the shafts between the aluminum rockers where they ride against the bolt spacers .

You may have to mill the rockers and the spacers provided with the rockers to center the roller on the valve tip to make room for hardened shims. Hardened shims should be used between all the steel spacers and aluminum rockers. Otherwise the bolt spacer will wear into the aluminum

When you buy the bolt spacers new they are all the same width, 4 wide 6 short. Then they are ground to fit the application for fitment. Every head is different. Watch your pushrod location where they travel through the head.
 
Oldmanmopar said:
You will need to have the stand milled off for Clearance.

One other thing I would like to mention is do not use the cap spacers on the bolts to ride directly on the Aluminum rocker . Place hardened shims on the shafts between the aluminum rockers where they ride against the bolt spacers .

You may have to mill the rockers and the spacers provided with the rockers to center the roller on the valve tip to make room for hardened shims. Hardened shims should be used between all the steel spacers and aluminum rockers. Otherwise the bolt spacer will wear into the aluminum

When you buy the bolt spacers new they are all the same width, 4 wide 6 short. Then they are ground to fit the application for fitment. Every head is different. Watch your pushrod location where they travel through the head.
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More good stuff ^^^^^^
 
Kendog 170 said:
Are there lefts and rights? I don't know maybe it's the pic angle what about this? Looks like disaster.

View attachment 1716088258
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You are not wrong! turns out that pedestal was interfering as well. I had to grind that one back a little bit and now its able to be centered. Now all I need to do is get the correct spacers.
Here is that rocker you were questioning now.
343958848_544238197784129_4524497524113169757_n.jpg
 
Well I think I about solved the problem, and I learned something.

Shaved some of the number 1 pedestal, Yes I know now that I didn't need to take it down that low. but it now clears the rocker. Also, like Kendog mentioned above I had to take the center pedestal in a little as well, it now clears just fine. Managed to do this without getting any contaminates in the engine as well. Here are some pictures of how they sit now. I will also be looking for the correct cap spacers or shims.



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Congrats. You've learned that setting up a Mopar wedge valvetrain can involve many trial setups and modifications to get it right, especially with aftermarket rockers. . It's not a small block chevy. It IS worth it to get it right the first time.
 
I think you're headed in the right direction for sure. Hughes Engines sells a pile of rocker shims, so you should be able to get an assortment. I would run thin ones between the rocker hold downs and rockers, so be prepared to maybe even get different thicknesses of the thick spacers, too. Once you get "all that" done, then you should contact Mike at @B3RE (B3 Racing Engines) and he'll show you how to tell if your actual rocker geometry needs correcting and help you get it done. No sense in doing half of it and leaving the other half undone.
 
RustyRatRod said:
I think you're headed in the right direction for sure. Hughes Engines sells a pile of rocker shims, so you should be able to get an assortment. I would run thin ones between the rocker hold downs and rockers, so be prepared to maybe even get different thicknesses of the thick spacers, too. Once you get "all that" done, then you should contact Mike at @B3RE (B3 Racing Engines) and he'll show you how to tell if your actual rocker geometry needs correcting and help you get it done. No sense in doing half of it and leaving the other half undone.
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Couldn't of said it better. No point in cutting corners with all the time and money into this engine.
 
Post #21 pics. Might just be the picture angle, but it looks like some of the rollers are not centered on the valve tip.
 
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