Does my geometry look off?
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Does my geometry look off?

  1. #1
    Senior Member H20MOFO's Avatar
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    Default Does my geometry look off?

    I had a rocker arm fall off a pushrod last time out(not sure where that thread went). Had a few comments that my pushrods looked a lil short. I'm not sure...maybe...it would be nice if they were cause I have some rocker arm to stud issues. The rocker arm I thought I broke has a groove below the last thread I thought was a break until I pulled it. I will try to edit some pics.
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ID:	119050 Having a heck of a time with pics tonight. The rocker stud I thought I broke just ha a grove from riding low on the rocker stud. I will keep workin on the pics.
    The pic is hard to see whats up....the intake on # 1 is at mid lift in the pic.
    Last edited by H20MOFO; 06-13-2011 at 08:18 PM.
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    Some guy obnoxious001's Avatar
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    The angle of the photo makes it difficult to judge from here, but hold a straightedge through the centers of the roller and trunion and see if it's parallel to the retainer. From the camera angle it looks like it's pointing upwards,, and therefore the pushrods would be short.

  4. #3
    gn7
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    If that valve in your above post is at mid lift, your PRs are short.


    Just based off this pic in your last thread, and looking at the exhaust at the far left, and the fact that the roller is that far inboard with a .700 lift cam, and over length valves, I would say this pic backs up that up.





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    Boat Nut sleekcrafter's Avatar
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    Maybe time to up grade rocker studs to ARP PRO SERIES they are better suited for the permalock fasteners.
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    Senior Member H20MOFO's Avatar
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    I am a dumb ass....that last pic was not midlift. I was a half a turn to far on the dial gauge. I dont think it looks to bad now...I dunno. I am riding waaaay low on this rocker stud not sure if that causing issues....or what to do about it. Starting to wonder if the exaust valve is bent....the spring is kissing one side of the pocket in the head...and lotsa room on the other. Fwiw cam is suposed to have .700 lift...I am measuring .692. Having a heck of a time with pics all of a sudden.
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    Edit....after looking at this pic...and laying a credit card across the pivot point and the rocker tip....I think they still look 2 short...let me know whatcha think guys. I guess I need to go buy one of those nifty little squares loke Steel has. =)
    Last edited by H20MOFO; 06-14-2011 at 07:55 AM.
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    Boat Nut sleekcrafter's Avatar
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    Were the guides honed for extreme duty marine use? what are you using for exhaust valves? Iconel?
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    Senior Member H20MOFO's Avatar
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    Quote Originally Posted by sleekcrafter View Post
    Were the guides honed for extreme duty marine use? what are you using for exhaust valves? Iconel?
    I doubt my ex-motor guy honed them...to be honest I have never heard of that before. On the exaust valve....they are stock...what ever brodix puts in em. I bought them assambled. Not sure what they are. My pushrods would appear to be 9.75....I am having a hard time even seeing any longer ones to order. And most of the adjustable pushrods I am seeing only go to 9.8. To look at that valve...something doesnt look right...hard to see in the pic.
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    Last edited by H20MOFO; 06-14-2011 at 09:17 AM.
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    Quote Originally Posted by H20MOFO View Post
    I doubt my ex-motor guy honed them...to be honest I have never heard of that before. On the exaust valve....they are stock...what ever brodix puts in em. I bought them assambled. Not sure what they are. My pushrods would appear to be 9.75....I am having a hard time even seeing any longer ones to order. And most of the adjustable pushrods I am seeing only go to 9.8. To look at that valve...something doesnt look right...hard to see in the pic.
    I found this to be an easier way to chk midlift. Valve on the seat, spread your calipers to the Midlift height - across CL of Trunnion and CL of roller tip, keeping it square with the Retainer (90 deg to valve stem). If it's square your good, if not it's easy to see which way you have to go. This works when checking with Hyd Lifters, or if you can't change to Mock-up springs.

    I'd agree with you, but then we would both be wrong

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    gn7
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    H2OMOFO, Its seems painfully appearent that the PRs are to short. There is no pic you have posted yet where the roller center isn't above the center of the trunnion.
    I don't need a little T square to see that the roller center is well above the trunnion center in this pic:


    Those 2 lines you drew should be at 90*. Maybe they are in person, but they sure as hell aren't in this pic. And seriously, I doubt they are. Let me try it this way. That line going through the trunnion and roller centers, it needs to be PARALELL with the top of the retainer. PARALELL, no even with or flush with, just dead inline with. Your lift is probably of because, either you didn't subtract the las for the stated lift. All cams are listed as gross lift without the lash subtrsacted. Also, the wrong length PR will result in less lift. Specially too short.



    Is it this pic, or has that valve tip been hammered through all this? It so, get it fixed. It will just tear up you valve guide. Not counting the fact that if its a rounded as it looks, really tough to keep a rocker on.


    You can get longer adj. PRs alot of places. Jegs has them.
    LINK: 9"-10.170" adj PR

    Your not going to find the correct PR in some catalog. Summit sells virtually every imaginable length on line, and you can order custom lengths from Manton, Smith Bros. and Trend. This just the lengths Summit sells in Scorpion alone. Once you open the link, just click on the "show all" for both intake and exhaust.
    LINK: Scorpion PR list

    I know this all seems like a pain in the ass, and it is. But would you run your lash at twice recommended? Or run a .080 spark gap? Run your timing at 12* total? While this may not seem as important, it can be. Right is right, and wrong is wrong.



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    Last edited by gn7; 06-14-2011 at 02:59 PM.

  12. #10
    gn7
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    Quote Originally Posted by 28Eliminator View Post
    I found this to be an easier way to chk midlift. Valve on the seat, spread your calipers to the Midlift height - across CL of Trunnion and CL of roller tip, keeping it square with the Retainer (90 deg to valve stem). If it's square your good, if not it's easy to see which way you have to go. This works when checking with Hyd Lifters, or if you can't change to Mock-up springs.

    This is very similar to the way Miller explains how to setup his shaft rockers to determine the stand hiegth. It works, but you should have a lash feeler gauge in their t be the most accurate. If you were to check this arrangement as is at actual mid lift, I believe you would find the rocker just slightly past 90*. Not by much, and a hell of alot closer than H2OMOFO is right now.

    The main thing to keep in mind here is that the lower caliber jaw is not even with the top of the retainer like it looks here, but rather dead paralell with it, to assure that the caliber is 90* to the valve. This particular pic is a little disceiving at first glance.


    H2OMOFO, notice how far out the roller is in 28Eliminator's pic. This is pretty normal for a after market hjead with long valves and a cam in the .700 range. Yours seem to be much further inboard than this. That was the first give away.



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  13. #11
    Senior Member H20MOFO's Avatar
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    Thanks for the help and your patients guys. It looks obvious to me now...especially after I played dot to dots with the pic. I'm on it...and thanks info on the longer pushrods.(as far as buying longer than 9.75)
    Last edited by H20MOFO; 06-14-2011 at 04:17 PM. Reason: clarification
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  14. #12
    Some guy obnoxious001's Avatar
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    Quote Originally Posted by H20MOFO View Post
    Thanks for the help and your patients guys. It looks obvious to me now...especially after I played dot to dots with the pic. I'm on it...and thanks info on the longer pushrods.(as far as buying longer than 9.75)
    The "easy" way to do it if you want 3/8" .080" wall pushrods is Manley, since they have a complete selection of lengths that are sold "on the shelf". Hopefully you have adjustable pushrods so you can determine proper length?

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    Boat Nut sleekcrafter's Avatar
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    As bad as it is, I think you got lucky. This was likely the start of catastrophic engine failure. IMO the head should come off, then have the valves, and guides checked. The honing of the guide frees up the valve, reducing the chance or eliminating of a valve hanging up. Inconel Exhaust valves, are a step above the severe duty SS valves, the stem of the valve does not grow, nearly as much as a SS valve. Once the head kisses the valve, an ugly situation quickly snowballs. More than a few engines have gone way of the dropped valve. Nip it in the butt, before it really bites you.
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