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Roller Rocker questions

Toms007

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Guys,I need some help with some RR's I bought (used 4000 miles). Crane Cams Gold Roller Rockers (PN 10758-16). They came with screw in studs (I'm short one), lock nuts and pushrods. First off do I need to replace the rocker studs? The rockers have a 3/8" mounting hole, are my 94 LT1 (stock) studs 3/8" or 10mm? I can't seem to find on Crane's site any info. Did these rockers come with these studs? I can only assume they did. What I find on Crane site talks about these studs being used for non self-aligning rockers the rockers I got are self aligning.

Secondly does anyone have any info/suggestions for me when I do the change over? I will be doing this without removing the heads. I will be replacing the valve springs as well (low mileage LT4 springs, retainers, shims, etc.) I have never done a valve spring change out with the heads on (and it's been several years since I did one with the heads off....like 32).

I'm up for any info/help/suggestions you guys can come up with.

Thanks in advance.
 
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Toms007

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Lots of views but no advice/help? Surely someone out there has done this.
 

8388

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You should be ok with the 3/8" studs if your stock. Are these the self aligning rockers? If not, it would be best to use hardened guide plates. The stock plates are too wide and allow the push rods too much play. Some believe that the push rods need to be hardened aswell, but I've never had any problems with the factory push rods and hardened guides. As for replacing the springs, I presume you know you need to pressurize each cylinder. I would check the all the guide seals since your going to be there, and check all your clearances, coil bind, retainer to guide, etc.
 
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Toms007

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Yes the "new" rockers are self aligning, and I do know about the pressurizing the cyl. I am planning on replacing the valve seals as well. What can you tell me about the adjusting of the rockers arms? Back in the day (early 70's) when I did them we adjusted them running (big mess), From what I can see they now adjust them by torque (I think I read 18 # ft). Does this sound right?

Thanks for the response.
 

AdvancedAutoCC

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When the rocker is in proper position (see below) adjust the nut and take up the slack until the pushrod is just seated (NOT preloaded). If you're uncomfortable with the "feel" of it, use a small light to look down into the lifter cup.
Assuming you've adjusted properly, turn the nut 3/4 turn, tighten Allen setscrew, tighten nut to "cinch" in place. Repeat on each cylinder.

Time and again, people ask "What's the best way to adjust?" I'll spell out what's worked for me in 27 years of wrenching.


For proper position and adjustment, do the following: As the exhaust valve starts to open, adjust the intake.

Roll the engine over (breaker bar or remote button on starter) and watch the intake valve - as it just closes, adjust the exhaust. Then use the above procedure for roller rockers (3/4 turn method).

Good luck to you!
 

8388

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(2) Callaway's (2) ZR1 (1) supercharged 35th
Good information above. You can usually adjust two rockers at the same time with the above directions. Also, put alittle oil on both ends of the push rod, and some on the valve tip for lubrication. When replacing the rocker studs, put some sealer on the threads.
 
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Toms007

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Good information above. You can usually adjust two rockers at the same time with the above directions. Also, put alittle oil on both ends of the push rod, and some on the valve tip for lubrication. When replacing the rocker studs, put some sealer on the threads.

AdvancedAutoCC, thank you for your very complete explaination on how to adjust the rockers, that's the way I will do them.

8388, when you say put some "sealer" on the threads are you talking about Lock tite? Red or Blue? Or some other type of sealer?

Thanks for the replies.
 

8388

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8388, when you say put some "sealer" on the threads are you talking about Lock tite? Red or Blue? Or some other type of sealer?

Any sealer that can handle the temp and oil. Some of those threads go all the way down to the head runner ports. Oil can seep down, and cause the engine to smoke.
 

AdvancedAutoCC

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AdvancedAutoCC, thank you for your very complete explaination on how to adjust the rockers, that's the way I will do them.

8388, when you say put some "sealer" on the threads are you talking about Lock tite? Red or Blue? Or some other type of sealer?

Thanks for the replies.
No problem... the sealer preferred is liquid Teflon sealant (found at your local parts store).. good to have on hand when you need to reseal your L98 intake manifold. :D
 
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Toms007

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OK, I have all the parts and tools accumulated for this job.

Crane Roller Rockers w/lock nuts (ARP screw-in studs, if I need them)
LT4 valve springs, w/retainers, keepers, shims, pushrods
Valve stem seals (OEM type)
Lubriplate (to lube the parts)
Teflon sealer
valve cover gaskets
valve spring compressor
"Pigtail" hose to pressurize the cylinder
New NGK TR55 platinum plugs
Valve spring height micrometer

Am I missing anything vital?

One question on the lock nuts, the allen head screw is what adjusts the rocker arm and the nut locks it into place? Or the other way around?

Thanks for the help.
 

AdvancedAutoCC

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One question on the lock nuts, the allen head screw is what adjusts the rocker arm and the nut locks it into place? Or the other way around?

Thanks for the help.

The nut adjusts the rocker, the Allen setscrew locks it in place.
 

scotch1

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Toms94.
I'm interested in how you mad out? And how you like them.
And how everything came together.
Any trouble installing the Crane Roller Rockers??
As I'm planning to install 1.6 RR in my L98.
Tom
 
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Toms007

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:eyerole Well.......I haven't got to it yet...... I am embarrassed to say that, but I have been sooooo busy on the weekends that I haven't even started. This weekend coming up we are headed to KC to visit daughters/grandkids. The weekend after that I have to prep the kitchen for ceramic tile which will be laid starting the 30th, so it won't be in the next two weeks at least. I will post as soon as I get it started and then again when I get it done. Thanks for asking.
 
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Toms007

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Well,I just got done doing this job. It was about as much work as I was anticipating. There were a few items that were more of a problem than others.

Sunday afternoon I started this little project. I started on the drivers side first. Everything went according to what I was expecting. I had a couple of interruptions but I had the springs changed out and the rockers on by around 6 pm. I then pulled the pass side valve cover off and removed the rockers from that side and then I got things cleaned up.

Tonight I got started about 5:30. I was able to get the front 2 cylinders springs changed out in about 10 minutes. I took a break and ate supper then went back out to do the last 2. As expected these were the PITA. Took me about an hour just to get the air hose into the back cylinder to pressurize it. After I got it, it only took a few minutes to actually change the springs out. The next cylinder up only took about 15 minutes to get the air hose into the spark plug hole, and again only a few minutes to change them out. I proceeded with the adjustment of the valves, this took about an hour. I then got it all buttoned back up and she fired the first time.

She doesn't run real smooth at idle, not really rough, just not smooth. And these rockers appear to be rather noisy, I think I had heard that Roller rockers were noisier than standard. It's too late to take it out for a test drive, I'll try to do that tomorrow. I did install new plugs and serpentine belt.

Any comments/suggestions from the crowd would be appreciated.
 

Greg Albers

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Stock valve covers?

Hi
Do you have stock valve covers? If so what did you have to do to get clearance for the rocker arms?
 
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Toms007

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Yes Greg, I have stock valve covers. I just cut the little tabs off.
 

scotch1

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Hi.
How do you like them so far?
You mentioned a rough idle?
Has it smoothed out any??
Do the new rockers make any noticeable noise?
Tom.
 
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Toms007

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I haven't had time to drive it at all since I got it finished up. I am thinking that I am going to pull the valve covers off and re-adjust the valves again, to see if that will smooth up the idle. I could have them too tight, I am thinking about backing off the adjustment 1/4-1/2 turn. The new rockers are, without a doubt, noisier. By backing them off they should, maybe quiet some as well.

We had a winter storm move in and I don't anticipate being able to take it out for a while to see how much better/different she runs. After 30+ years of not doing anything like this, I was just tickled that she fired up and ran!:L
 
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Toms007

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Alright, here's the latest and hopefully the last post on this little job. I took the time tonight to pull the valve covers off and readjust the rockers. I did have to pull the serpentine belt and loosen the alt in order to remove the driver side valve cover.

I re-adjusted the valves to 1/2 turn past zero lash, the engine idles smooth as silk and she runs like a bat out of h3ll. I obviously had them adjusted too tight. But I learned that pulling the valve covers off isn't that big of a job and that I can do it quicker than I thought possible. I did the re-adjust in a little over and hour, including taking two phone calls. Thanks to all who made suggestions and offered advice, you all are the greatest.
 

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