Rocker advice on how to proceed
Le Mans Master
Joined: May 2008
Posts: 9,063
Likes: 2,736
2022 C3 of the Year Finalist - Modified
The AFR 195 Race heads in my 406 came with adjustable / split guides.......was the builder supposed to weld them after adjusting them? Is that mandatory? I would not be surprised if it was not another mistake this guy made.
Le Mans Master
Joined: Aug 2017
Posts: 8,336
Likes: 2,810
From: Cool Northern Michigan
I ordered raised guide plates from Jegs to see if they make a difference.
https://www.jegs.com/i/JEGS/555/202001/10002/-1
Will update once I try them.
https://www.jegs.com/i/JEGS/555/202001/10002/-1
Will update once I try them.
And NewB. Usually the hole for the rocker stud is drilled over-sized. Just enough to allow adjustments.
Joserpaq, going back over your opening statement you said you wanted to check the lash.
I also noted going over the photos that not one spring appears to be compressed.
So, now I am putting two & two together.
How was the lash?
Last edited by HeadsU.P.; May 24, 2022 at 07:55 PM.
Thread Starter
Racer
Joined: Nov 2020
Posts: 265
Likes: 76
Jegs shows them up-side-down.
And NewB. Usually the hole for the rocker stud is drilled over-sized. Just enough to allow adjustments.
Joserpaq, going back over your opening statement you said you wanted to check the lash.
I also noted going over the photos that not one spring appears to be compressed.
So, now I am putting two & two together.
How was the lash?
And NewB. Usually the hole for the rocker stud is drilled over-sized. Just enough to allow adjustments.
Joserpaq, going back over your opening statement you said you wanted to check the lash.
I also noted going over the photos that not one spring appears to be compressed.
So, now I am putting two & two together.
How was the lash?
Thread Starter
Racer
Joined: Nov 2020
Posts: 265
Likes: 76
https://www.jegs.com/i/JEGS/555/20187/10002/-1
Le Mans Master
Joined: Mar 2004
Posts: 7,507
Likes: 1,513
From: Little Rock AR
These are the rockers I'm using. They are for 3/8 inch studs.
https://www.jegs.com/i/JEGS/555/20187/10002/-1
https://www.jegs.com/i/JEGS/555/20187/10002/-1
Might just be the angle of the photo from here. Those nuts are new to me. Never seen those before.
Last edited by stingr69; May 24, 2022 at 09:51 PM.
Le Mans Master
Joined: Mar 2004
Posts: 7,507
Likes: 1,513
From: Little Rock AR
The rocker arm nuts look like they might be some kind of poly locks???? But no room for the set screws??? The studs would need to be flat machined on top to seat a set screw. When you said you set the lash with your fingers that made me pause. This setup will allow your lash setting to back off and make a mess.
Those rockers usually come with prevailing torque nuts. The last set of those rockers I bought came with the worst nuts ever. They were too weak to hold a lash setting. I just found a set of good used nuts that still held against the threads. No issues.
Those rockers usually come with prevailing torque nuts. The last set of those rockers I bought came with the worst nuts ever. They were too weak to hold a lash setting. I just found a set of good used nuts that still held against the threads. No issues.
Dr. Detroit
Joined: Mar 2012
Posts: 10,097
Likes: 4,027
From: New Braunfels Texas
Those raise guide plates are not going to solve anything......the intake need to move independent of the exhaust.....
You can see from the photos that the exhaust is on the stem and the intake is way off......if you slide a one piece guideplate over to straighten it out...it will just move the exhaust too far over.
@NewbVetteGuy I have not used the Jomar.....but they are pretty clever.....no rotation when you tighten it.....which is why a split one is a pain.....it wants to twist and bend sometimes.
No matter what happens here...the intake has to move 100% independent of the exhaust to fix this regardless of how it happened or why. If it were here it would be fixed in an afternoon as I keep split plates on the shelf for this exact reason.
Jebby
You can see from the photos that the exhaust is on the stem and the intake is way off......if you slide a one piece guideplate over to straighten it out...it will just move the exhaust too far over.
@NewbVetteGuy I have not used the Jomar.....but they are pretty clever.....no rotation when you tighten it.....which is why a split one is a pain.....it wants to twist and bend sometimes.
No matter what happens here...the intake has to move 100% independent of the exhaust to fix this regardless of how it happened or why. If it were here it would be fixed in an afternoon as I keep split plates on the shelf for this exact reason.
Jebby
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Dr. Detroit
Joined: Mar 2012
Posts: 10,097
Likes: 4,027
From: New Braunfels Texas
Jebby
Le Mans Master
Joined: Aug 2017
Posts: 8,336
Likes: 2,810
From: Cool Northern Michigan
Joserpaq,
Looking over your photos again, it almost looks the guide plate slot is too large. Makes you wonder if they are for the larger size pushrods.
The new guide plates you ordered will serve their purpose. You sure don't need split & welded plates.
Going back to post 23, is a clue. Without getting into 100 different opinions on setting valve-lash, I think you went a little soft on yours.
After zero lash, some people go 1/2 turn, 3/4 turn or one full turn. But yours leaves some lash, especially if the lifters bled down later considerably.
And the rocker arm hardware is somewhat of a suspect as Sting pointed out.
Looking over your photos again, it almost looks the guide plate slot is too large. Makes you wonder if they are for the larger size pushrods.
The new guide plates you ordered will serve their purpose. You sure don't need split & welded plates.
Going back to post 23, is a clue. Without getting into 100 different opinions on setting valve-lash, I think you went a little soft on yours.
After zero lash, some people go 1/2 turn, 3/4 turn or one full turn. But yours leaves some lash, especially if the lifters bled down later considerably.
And the rocker arm hardware is somewhat of a suspect as Sting pointed out.
Melting Slicks
Joined: Jun 2016
Posts: 2,979
Likes: 332
From: Woodinville WA
Jegs shows them up-side-down.
And NewB. Usually the hole for the rocker stud is drilled over-sized. Just enough to allow adjustments.
Joserpaq, going back over your opening statement you said you wanted to check the lash.
I also noted going over the photos that not one spring appears to be compressed.
So, now I am putting two & two together.
How was the lash?
And NewB. Usually the hole for the rocker stud is drilled over-sized. Just enough to allow adjustments.
Joserpaq, going back over your opening statement you said you wanted to check the lash.
I also noted going over the photos that not one spring appears to be compressed.
So, now I am putting two & two together.
How was the lash?
Adam
Le Mans Master
Joined: Oct 2010
Posts: 6,945
Likes: 851
From: melbourne florida
2023 C3 of the Year Finalist - Modified
Could you have some different length pushrods ? I'd look at the rocker ball size. Those pushrods that are canted are they looser than others? Otherwise it probably is the guideplate.
Le Mans Master
Joined: Aug 2001
Posts: 7,804
Likes: 4
From: Standing still with all my might Texas
Cruise-In X Veteran
St. Jude Donor '09-'11
I’m far from an expert, but it looks like the rocker arms are tightened down way too far on the studs due to the pushrods being too short.
Le Mans Master
Joined: Aug 2017
Posts: 8,336
Likes: 2,810
From: Cool Northern Michigan
That ^^^^^^^^^^^^^^^^^^ brings up a good point. Just about all aluminum after-market heads state right in the owner's manual, new pushrods of 0.100 longer may be required. Always double check length with a "push-rod length checking tool" to verify before proceeding.
Melting Slicks
Joined: Jul 2006
Posts: 2,293
Likes: 494
From: Salmon Arm, BC
Have you considered guided rocker arm and ditching the guide plates?
some folks frown on these, but I've used them for 20 years and have never had an issue using them to 7300 RPM.....
Something to think about. Here's something similar to what you have.....
https://www.jegs.com/i/PRW/228/0835005/10002/-1
some folks frown on these, but I've used them for 20 years and have never had an issue using them to 7300 RPM.....
Something to think about. Here's something similar to what you have.....
https://www.jegs.com/i/PRW/228/0835005/10002/-1
Team Owner
Joined: Mar 2002
Posts: 44,698
Likes: 1,835
From: Huntsville AL
Have you considered guided rocker arm and ditching the guide plates?
some folks frown on these, but I've used them for 20 years and have never had an issue using them to 7300 RPM.....
Something to think about. Here's something similar to what you have.....
https://www.jegs.com/i/PRW/228/0835005/10002/-1
some folks frown on these, but I've used them for 20 years and have never had an issue using them to 7300 RPM.....
Something to think about. Here's something similar to what you have.....
https://www.jegs.com/i/PRW/228/0835005/10002/-1
Le Mans Master
Joined: May 2007
Posts: 5,038
Likes: 1,121
From: North tonawanda NY
I used these on my new aluminum heads... https://www.ebay.com/itm/17405060935...oAAOSwAhZic88C
but I also have shorter pushrods and longer valves than stock... (retro roller lifters needed shorter measured rods)
but I also have shorter pushrods and longer valves than stock... (retro roller lifters needed shorter measured rods)
Le Mans Master
Joined: May 2007
Posts: 5,038
Likes: 1,121
From: North tonawanda NY
Melting Slicks
Joined: Jul 2006
Posts: 2,293
Likes: 494
From: Salmon Arm, BC
Le Mans Master
Joined: Aug 2017
Posts: 8,336
Likes: 2,810
From: Cool Northern Michigan
And some companies have a stainless harden washer on each side of the roller tip, that is a larger diameter than the roller itself. Thus keeping it dead center on the valve stem tip.