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my valves won't close help

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Old 07-27-2010, 12:01 AM
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HI Guys.
ok so I installed the g5x3 114 cam, got my felpro gaskets 0.41 and my heads milled to 62cc
i put some checking springs to check my piston to valve clarance
i notice when tighting my rockers the valves open and when rotating enigne by hand many revolutions the valves never close all the way. I beleive i need shorter pushrods. has anyone had this problem.
Attached Thumbnails my valves won't close help-072620101980.jpg   my valves won't close help-072620101981.jpg  
Old 07-27-2010, 12:22 AM
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What length are you currently using? Do you have a PR checker?
Old 07-27-2010, 12:31 AM
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i will get a push rod checker tomorrow and update.
Old 07-27-2010, 12:36 AM
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Non adjustable rockers means you NEED to check for proper pushrod length.

Comp Cams #249-7702-1

Pushrod Length Checker, 6.800'' - 7.800''

That comp cams pushrod checker can be found for $17 or less if you look hard enough.



THEN

Check these out. I didn't read or watch all of them but they should get you where you need to be.
http://www.compcams.com/information/Products/Pushrods/

http://www.carcraft.com/techarticles...th/index1.html

http://www.youtube.com/watch?v=qw5PWiOwXhI
Old 07-27-2010, 04:27 AM
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How exactly are you checking PTV? Are you using solid lifters? If so, you need to be at zero lash before checking. Are you using the dial indicator method? Need a lot more information.

Also, that video is for stud mounted rockers and doesn't apply to a shaft mounted rocker. The video is showing how to set the wipe pattern, which with stud mounted rockers it is set with pushrod length. For the shaft mounted LS1 rockers, you set the wipe by adjusting the rocker mounting height with either shims or removal of material from the rocker stand.
Old 07-27-2010, 04:25 PM
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ok so i measure my push rod lenth they are 7.4
I even called LG and they said they have milled even more off the heads and have used the same push rods with no problem, also said that cam fits F body and Y body.
is the cam circle larger on the g5 ? still wondering why the valves ani't closing all the way when others have used this combo with no problems ....
Old 07-27-2010, 04:49 PM
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I'd bet your pushrods are too long!
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Old 07-27-2010, 07:11 PM
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Originally Posted by yanman
ok so i measure my push rod lenth they are 7.4
I even called LG and they said they have milled even more off the heads and have used the same push rods with no problem, also said that cam fits F body and Y body.
is the cam circle larger on the g5 ? still wondering why the valves ani't closing all the way when others have used this combo with no problems ....

We are asking you to measure the distance from the lifter to the rocker. Not the actual pushrod. Although it is good to double check things.

Get the checker pushrod and expand it until you achieve the proper wipe pattern then measure the checker. that's the pushrod length you need.
Old 07-27-2010, 09:55 PM
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This may be a stupid question but.
Just out of curiosity is this only happening on the valves that the check springs are on?
The check spring may not be strong enough to close the valve all the way.
Old 07-27-2010, 10:44 PM
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ABQ99TA <----- yeap , i just put the full valve train assembly on and rotated many times all the valves close.... finally, check springs don't close them, i just found that out after playing around with that all day...
Old 07-28-2010, 04:41 AM
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Originally Posted by Cheatin' Chad
We are asking you to measure the distance from the lifter to the rocker. Not the actual pushrod. Although it is good to double check things.

Get the checker pushrod and expand it until you achieve the proper wipe pattern then measure the checker. that's the pushrod length you need.
Pushrod length will not effect the wipe pattern unless they are adjustable rockers. If the OP is checking PTV, he needs to do this at zero lash with check springs.
Old 07-28-2010, 04:43 AM
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Originally Posted by yanman
ABQ99TA <----- yeap , i just put the full valve train assembly on and rotated many times all the valves close.... finally, check springs don't close them, i just found that out after playing around with that all day...
How are you checking PTV, which was your original question?
Old 07-28-2010, 12:06 PM
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Originally Posted by yanman
ABQ99TA <----- yeap , i just put the full valve train assembly on and rotated many times all the valves close.... finally, check springs don't close them, i just found that out after playing around with that all day...
Sweet




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