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Discussion Starter · #1 · (Edited)
So when setting up the rockers and such noticed i had to get some adjustable guide plates, well i set them up side to side,and went along to setting cold lash, when i noticed turning it over that the pushrods were binding, i had to deepen the slot on the guides about 1/8" deeper,I could have gotten by with a 1/16", now no bind,everything seems to be ok. Is this something someone has seen before?Or is something else going on.I measured for correct pushrod length.
 

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There are a couple of potential issues here, maybe you could post a photo.

But usually, doing what you did is the right way to fix it.
 

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Discussion Starter · #3 · (Edited)
There are a couple of potential issues here, maybe you could post a photo.

But usually, doing what you did is the right way to fix it.
Well let me try and explain,when rocker was on it's way down(P/R end)the rocker was pushing the p/r against the bottom of the slot, which in turn the p/r at the lifter end was coming up out of the pocket in the lifter cocking the p/r, it's like if you take pencil and push side ways on one end the opposite end goes the other way, so the rocker is pushing that end outward the lower end lifter is trying to go inward.make any sense?I probably could have gotten by with just a 1/6" clearance.
 

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I don´t exactly understand what´s going on but its pretty normal that guideplates needs to be adjusted and even grind some to make them work properly, canted valve angles are one "problem" with BBC. One thing though...they are ´guideplates´ so no need for excessive clearence that´s why your pushrods are hardered but binding is a big no, no! :anim_25:
 

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Discussion Starter · #5 ·
I don´t exactly understand what´s going on but its pretty normal that guideplates needs to be adjusted and even grind some to make them work properly, canted valve angles are one "problem" with BBC. One thing though...they are ´guideplates´ so no need for excessive clearence that´s why your pushrods are hardered but binding is a big no, no! :anim_25:


I'm just checking to see if you undestand what i meant by my post.I'm not talking about side to side clearance of the guide, i'm talking about the depth of the guide.The rocker was pushing the p/r into the back of the guide and bottoming out.So i deepen the slot in the guide.
 

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Are you sure about the pushrod length? If the pushrods were significantly too short, the rocker would rotate back far enough to move the pushrod (too much) closer to the pivot and guide.
How does the tip center on the valve stem when the valve is closed (and the pushrod is too close to the guide)? It shouldn't be all that far from the center of the stem. And when the valve opens and closes, the rocker tip should travel pretty close to the same distance from either edge of the stem.
If it only happens when the valve closes, it seems like the rocker goes too far back, and when the valve opens the rocker doesn't go far enough forward compared to how far it goes back.
 

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Discussion Starter · #7 ·
Are you sure about the pushrod length? If the pushrods were significantly too short, the rocker would rotate back far enough to move the pushrod (too much) closer to the pivot and guide.
How does the tip center on the valve stem when the valve is closed (and the pushrod is too close to the guide)? It shouldn't be all that far from the center of the stem. And when the valve opens and closes, the rocker tip should travel pretty close to the same distance from either edge of the stem.
If it only happens when the valve closes, it seems like the rocker goes too far back, and when the valve opens the rocker doesn't go far enough forward compared to how far it goes back.
Here are 2 pictures, intake, exhaust.Of the roller tip pattern.I think they look ok with all that i have read.Am i wrong?
 

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Here are 2 pictures, intake, exhaust.Of the roller tip pattern.I think they look ok with all that i have read.Am i wrong?
They seem OK, but it's hard to tell on the exhaust, the tape looks lower than the marks, more so at the top. Is that marks in ink?
If the roller isn't getting close to the edge of the stem, it must be something else. Stock ratio rockers?
Your description sounded pretty extreme, dislodging the pushrod in the lifter?
OTOH, Rick said it didn't sound that unusual, maybe I need to get out more...
 

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Discussion Starter · #11 ·
They seem OK, but it's hard to tell on the exhaust, the tape looks lower than the marks, more so at the top. Is that marks in ink?
If the roller isn't getting close to the edge of the stem, it must be something else. Stock ratio rockers?
Your description sounded pretty extreme, dislodging the pushrod in the lifter?
OTOH, Rick said it didn't sound that unusual, maybe I need to get out more...
Picture isn't as clear, but the roller is basically centered over the center of the lash cap. Doesn't come close to edge at all.I could have been ok with just deepening the slot by 1/16, but took out 1/8th.So i would think that by just needing a 1/16th removed, were not talking extreme are we?

rockers are comp cams magnum 1.72
 

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Discussion Starter · #12 ·
Jim, things look pretty good to me.
Yes that's what i'm thinking too, since clearanceing
the guide plate everything looks normal, i think i put 5 miles on the motor i turned it so many times just watching all rockers lifters push rods.

When installing rocker studs, can you use the headbolt sealant on them, or do i need some type of locker, like loctite, they do need to be sealed though since some protrude into the intake runner.
 

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Discussion Starter · #13 · (Edited)
What ratio rockers do you have. 1.7 ,1.73.
What heads did you end up with.
If you bought the Pro Comps they take standard style guidplates.
I tried several brands ended up with adjustable plates.

1.72 rockers comp/cams roller tip.
I bought some pro comp heads oval port
installed manley valves
isky springs
comp cams retainers and keepers
lash caps
 

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Just had the same issue, pushrod getting stuck and coming out of the lifter. This was with the right length as verified by thr mark on the valve tip.

I haven't fixed it yet but about to check it out.
 
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