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  1. #1
    Member fine69's Avatar
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    Default Do Roller Tip Rocker Arms Need Constant Adjusting?

    I have a recurring problem with my roller tip rocker arms... they keep becoming misaligned with the valve/spring! I adjusted them last week, and the engine was running nice and strong. Today it started missing, sputtering and backfiring again. I removed the valve cover, and the rocker arms were misaligned again.

    I have the Performer RPM .510 lift cam (hydraulic) and wanted to be able to use the LT-1 style valve covers. These are 1.5 ratio roller tip rocker arms.

    I attached a photo. Is this milagnment and readjustment characteristic of these type of rocker arms? Should I revert to the standard style i.e., "shoe" type? Any suggestions/recommendations are appreciated.

    Thanks!
    1969 Corvette Convertible (build date December 14, 1968),
    L-36 427, 390 hp (3963512 block; 3964290 heads), Muncie M-21, Monza Red, Black Top & Black Interior. VB&P Gymkhana 550 lbs/inch coil springs, Bilstein Sport shocks.
    In progress... full body-off restoration.

    1972 Camaro Z-28, Rally Sport, Cranberry Red/Black Stripes.
    LS-6 454/425, Muncie M-21, 9.8:1 CR, Lunati 60204 Voodoo Cam (Dur 276/284, Lift .554/.572), Holley 3310-3 (750 CFM), Weiand 8019 Stealth Intake, 3.73:1 Rear, Flowtech Headers 1.75" Primaries, Chambered Exhaust, Custom Works GT Coil Springs, Hotchkis Sport Shocks.

  2. #2
    Gone but not forgotten bossvette's Avatar
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    Do you have pushrod guideplates installed?
    Have you thought about "poly-locks"?

    I had an issue with a 305 I built for my YT that required "Self-aligning" rockers with early style heads that should not be needed but looks like you have aftermarket heads. Try contacting the manufacturer to see what style rockers they recommend.

  3. #3
    Member LT4man's Avatar
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    I agree with bossvette. Easy for me to say!

    At any rate, you have a grrrrrrreat lookin' engine! I can just imagine the work you put into your baby!

    Save The Wave!
    An attendee at all the CruiseFests including the one which never happened.


    Autosig (Shadow) A

  4. #4
    Member Jack's Avatar
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    Quote Originally Posted by fine69
    I have a recurring problem with my roller tip rocker arms... they keep becoming misaligned with the valve/spring! I adjusted them last week, and the engine was running nice and strong. Today it started missing, sputtering and backfiring again. I removed the valve cover, and the rocker arms were misaligned again.

    I have the Performer RPM .510 lift cam (hydraulic) and wanted to be able to use the LT-1 style valve covers. These are 1.5 ratio roller tip rocker arms.

    I attached a photo. Is this milagnment and readjustment characteristic of these type of rocker arms? Should I revert to the standard style i.e., "shoe" type? Any suggestions/recommendations are appreciated.

    Thanks!
    Misalignment at #3 exhaust looks BAD!

    The others' problems are probably similar ...Here's a suggestion for #3 I&E ... the pushrod guide plate needs to be moved forward ... if you have not already doped the bottoms of rocker studs with teflon seal or other sealant ... remove, clean all threads & dope all of them ... if you have, then slightly loosen one pair of rocker studs at a time ... loosen just enough for the guide plate to be pried/shifted ... and shift the guide plate ... in the case of #3 it seems the guide plate needs to shift forward. Re-torque rocker studs ... while tightening studs, keep careful eye on guide plate to ensure it does not shift as you re-torque studs. G'Luck

  5. #5
    Member fine69's Avatar
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    Quote Originally Posted by bossvette
    Do you have pushrod guideplates installed?
    Have you thought about "poly-locks"?

    I had an issue with a 305 I built for my YT that required "Self-aligning" rockers with early style heads that should not be needed but looks like you have aftermarket heads. Try contacting the manufacturer to see what style rockers they recommend.
    Poly-locks... I'll look into that and will also contact Edelbrock. Thanks.

  6. #6
    Member fine69's Avatar
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    Quote Originally Posted by Jack
    Misalignment at #3 exhaust looks BAD!

    The others' problems are probably similar ...Here's a suggestion for #3 I&E ... the pushrod guide plate needs to be moved forward ... if you have not already doped the bottoms of rocker studs with teflon seal or other sealant ... remove, clean all threads & dope all of them ... if you have, then slightly loosen one pair of rocker studs at a time ... loosen just enough for the guide plate to be pried/shifted ... and shift the guide plate ... in the case of #3 it seems the guide plate needs to shift forward. Re-torque rocker studs ... while tightening studs, keep careful eye on guide plate to ensure it does not shift as you re-torque studs. G'Luck
    Thanks Guys...

    Do you all think regular, non-roller tip rockers would also help reduce this problem?

  7. #7
    Member black_81_vette's Avatar
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    Id check for coil bind at full lift or the spring retainer hitting the guide, ive seen the same thing happen because of those problems.

  8. #8
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    Quote Originally Posted by black_81_vette
    Id check for coil bind at full lift or the spring retainer hitting the guide, ive seen the same thing happen because of those problems.
    I don't remember if the rocker studs are screw in or press in? if they are the later the stud might be pulling out!

  9. #9
    Member fine69's Avatar
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    This is the Edelbrock Performer RPM setup. The intake, hydraulic cam, and heads are supposedly dyno'd to work together. The heads came with the valves, springs, guide plates, screw-in studs, but not the rocker arms (go figure).

    I'm going to cut an opening in a spare stamped valve cover and adjust the rocker arms with a running engine. I am anxious to get this running again and would like to do it tonight, but it's too darn cold out there (19 degrees Farenheit !) and the space heater in the garage just doesn't cut it!


    Here's a closeup of intake/exhaust rockers of #3 cylinder. It's puzzling why these would shift over like this....

    As good measure, I'm inclined to replace with regular rocker arms (with the longer slotted stud opening to compensate for the high lift), and locking nuts... good/bad idea?

  10. #10
    Gone but not forgotten bossvette's Avatar
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    apparently the #3 guide plate is off location, the valve, stud and pushrod should be in line. There is always the possibility the guideplate was manufactured off location. I would compare a known good one with your #3 and go from there; perhaps #3 is for a 7/16 stud and you have 3/8 studs that would allow for missalignment/cocking of the guide plate.

    the roller rockers are not causing the problem unless they are "backing off"

  11. #11
    Member Jack's Avatar
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    Now you show a bigger pic ... I can see even better ... and confirms. Sooo ... as I said before ... the guide plate NEEDS to be shifted forward.

    Valvetrain/motor will NOT live long like it is now!

    See the half-moon cutout around the headbolt in middle of guideplate??? see how the half-moon is not centered about headbolt but is shifted to rear??? ... needs to move forward! If you'll shift guideplate forward it'll cause the rockers to rotate counter-clockwise about studs and properly locate tips on top of valve stems. You should check ALL 8 guideplates for proper alignment & ALL 16 studs for proper torque.

    It is normal for these things to need alignment/setup when newly installed ... no real point in *****ing to EB.

    BTW ... MOST ... not all ... MOST screwin studs have 7/16 bottoms ... regardless if 3/8 or 7/16 tops. Accordingly, MOST guideplates' stud holes are larger than 7/16 ... so that they can be shifted.

    IMHO ... you need not buy different rockers nor cut up a valve cover nor buy polylocks ... but do correctly setup the guideplates for your motor.
    JACK

  12. #12
    Member fine69's Avatar
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    Bossvette and Jack,

    Thanks for the advice. I adjusted the guide plate, got the rocker arms nice and centered. I was able to go around the block, before she started sputtering and backfiring again. When I removed the valve cover, #3 cylinder rocker arms were offset again.

    I spoke with the owner of the machine shop who did this work, and he is going to actually send someone over to my house this Thursday to check it out and make the correct adjustments.

    (Sigh....) I'm get some other things done around the house for now... and will get back to this later... what a love/hate relationship.

    Thanks again, guys.

  13. #13
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    What is the proper way to align guide plates? I have guide plates on my heads, but I've never seen any info or pictures on the proper way to align them.

    Thanks,

  14. #14
    Member Jack's Avatar
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    Quote Originally Posted by fine69
    I adjusted the guide plate, got the rocker arms nice and centered. I was able to go around the block, before she started sputtering and backfiring again. When I removed the valve cover, #3 cylinder rocker arms were offset again.
    You didn't say if the guideplate was tight when you first checked it??? You didn't say if the guideplate had also shifted again along w/ rockers after you realigned plate??? If so, then plate ain't tight enough. If plate did not shift again, then you may have some bent pushrods. Regardless, I'd pull ALL 16 pushrods & check each for straightness.

  15. #15
    Member Jack's Avatar
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    Quote Originally Posted by glen242
    What is the proper way to align guide plates? I have guide plates on my heads, but I've never seen any info or pictures on the proper way to align them. Thanks,
    If your rockers are properly aligned to valve tips then the plate alignment is ok. Check that first ... then worry about it only if you see a problem. This should be checked upon valve train assembly. There's probably a book on this ... but I don't know where or what it is. If you'll read through my above posts ... and look closely at how your valve train works ... you should be able to figure it out ... it's really simple ... dumbazz me can do it.
    JACK

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