Broken rocker studs - Mustang Evolution

Go Back   Mustang Evolution > 4 Cylinder | V6 | Classic Mustangs || Tech and Talk > Classic Mustangs



Reply
 
Thread Tools Search this Thread
Please support our sponsors and let them know you heard about them here!
Old 08-16-2012, 03:40 AM   #1
Registered Member
Regular
 
Dadsgl67's Avatar
 
Join Date: Jul 2012
Region: California
Posts: 54
Broken rocker studs

Have a 289 bore 40 over stroked and a mild cam in it. I finished building her an had we running in December. On july 4 th I broke my 1 st rocker stud then 2 more since. I replaced all studs and am pretty sure I just broke another one on my way to work few hours ago. Does anyone have any ideas about why!? I'm going crazy over this. Thanks for any ideas
Dadsgl67 is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 08-17-2012, 07:53 PM   #2
Registered Member
Regular
 
BA68 mustang's Avatar
 
Join Date: Apr 2012
Region: New Jersey
Posts: 331
Did you put in the correct valve springs in with the cam?
BA68 mustang is offline   Reply With Quote
Old 08-18-2012, 05:31 AM   #3
Registered Member
Regular
 
Dadsgl67's Avatar
 
Join Date: Jul 2012
Region: California
Posts: 54
Yea
Dadsgl67 is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 08-18-2012, 06:10 AM   #4
Registered Member
Regular
 
blackhawk 1's Avatar
 
Join Date: Aug 2011
Region: California
Posts: 472
Re: Broken rocker studs

sell it
blackhawk 1 is offline   Reply With Quote
Old 08-18-2012, 04:33 PM   #5
Registered Member
Regular
 
Willi960's Avatar
 
Join Date: Jul 2012
Region: Nevada
Posts: 72
Sell it? Some people here are a little more attached to their cars than that man. I find that suggestion to be an insult. Maybe the loyally for classic mustang owners is deeper than that of newer ones.
Willi960 is offline   Reply With Quote
Old 08-18-2012, 09:09 PM   #6
Registered Member
Regular
 
BigpapaDean's Avatar
 
Join Date: Feb 2012
Region: Canada
Posts: 520
I also find that slightly insulting....sell the car??? Stupid comment.
BigpapaDean is offline   Reply With Quote
Old 08-18-2012, 11:04 PM   #7
Registered Member
Regular
 
mike Franklin's Avatar
 
Join Date: Jun 2011
Posts: 75
Yes. Stupid comment. Wish I had an answer. Many moons ago I had a '56 Ford that loved to bend pushrods. Never did figure it out. Wonder if your overtightening the studs??
mike Franklin is offline   Reply With Quote
Old 08-19-2012, 12:24 AM   #8
Registered Member
Regular
 
BA68 mustang's Avatar
 
Join Date: Apr 2012
Region: New Jersey
Posts: 331
I'd put a less aggressive cam in?
BA68 mustang is offline   Reply With Quote
Old 08-19-2012, 12:31 AM   #9
Registered Member
Regular
 
Dadsgl67's Avatar
 
Join Date: Jul 2012
Region: California
Posts: 54
I have been threw hell and back w Sally and I'll never sell her! That's my baby and she may be nickel and dimming me but it's money we'll spent beats waisting it on drugs or guys or clothing. A good mechanic fixes their cars when something goes wrong not sells it. That's like saying you got in a fight with your wife over nothing and now getting a divorce.
An I have checked all specs an They seem to be right. I may have to change the cam thanks for all who actually gave good advice, realistic advice much appreciated
Dadsgl67 is offline   Reply With Quote
Old 08-20-2012, 02:08 AM   #10
Registered Member
Regular
 
Willi960's Avatar
 
Join Date: Jul 2012
Region: Nevada
Posts: 72
Atta girl. Hope you figure it out.
Willi960 is offline   Reply With Quote
Old 08-20-2012, 04:41 AM   #11
Registered Member
Regular
 
Dadsgl67's Avatar
 
Join Date: Jul 2012
Region: California
Posts: 54
I changed out all my studs so far so good ( knock on wood) I sent the old studs to get strength tested results to be seen
Dadsgl67 is offline   Reply With Quote
Old 08-20-2012, 05:08 AM   #12
Road Trip!
Supporter
 
Join Date: Jun 2006
Region: Missouri
Posts: 8,779
Re: Broken rocker studs

Can you get me a close up picture of the heads, studs and rockers you are using?

Are you sure the valve springs are installed correctly and you are not experiencing coil bind?
Trojan Horse is offline   Reply With Quote
Old 08-20-2012, 12:07 PM   #13
Registered Member
Regular
 
Dadsgl67's Avatar
 
Join Date: Jul 2012
Region: California
Posts: 54
Do you have Facebook by chance All the pics are on there
Dadsgl67 is offline   Reply With Quote
Old 08-20-2012, 03:42 PM   #14
Road Trip!
Supporter
 
Join Date: Jun 2006
Region: Missouri
Posts: 8,779
Re: Broken rocker studs

Quote:
Originally Posted by Dadsgl67 View Post
Do you have Facebook by chance All the pics are on there

Yes, Who do I look for?
Trojan Horse is offline   Reply With Quote
Old 08-21-2012, 03:13 AM   #15
Registered Member
Regular
 
Dadsgl67's Avatar
 
Join Date: Jul 2012
Region: California
Posts: 54
Mustangmissy67 or missy Perez it's the same profile pic
Dadsgl67 is offline   Reply With Quote
Old 08-21-2012, 03:37 AM   #16
Road Trip!
Supporter
 
Join Date: Jun 2006
Region: Missouri
Posts: 8,779
Re: Broken rocker studs

Quote:
Originally Posted by Dadsgl67 View Post
Mustangmissy67 or missy Perez it's the same profile pic

Ok I found you under Missy Perez (Mustang Missy), I didn't see any pics of the rocker studs, so I sent you a friend request from my FB account (Ford Nutz) in case we have to be friends there for me to be able to see more pictures. You can un-friend me afterwards or not accept as you wish.
Trojan Horse is offline   Reply With Quote
Old 08-21-2012, 04:46 AM   #17
Road Trip!
Supporter
 
Join Date: Jun 2006
Region: Missouri
Posts: 8,779
Re: Broken rocker studs







Ok, got them, I need to crash right now, I'll continue the diagnosis discussion after I wake. Sorry.
Trojan Horse is offline   Reply With Quote
Old 08-21-2012, 07:55 AM   #18
Registered Member
Regular
 
Dadsgl67's Avatar
 
Join Date: Jul 2012
Region: California
Posts: 54
Thanks you all for your help.
Dadsgl67 is offline   Reply With Quote
Old 08-21-2012, 03:32 PM   #19
Road Trip!
Supporter
 
Join Date: Jun 2006
Region: Missouri
Posts: 8,779
Re: Broken rocker studs

Ok, from what I can see I have more questions.

What heads are those?
Did you use a pushrod length checker to select the correct length pushrods?
Did you check the installed height of the valve springs?
What procedure did you use to adjust the valve lash?

Check the roller tips, valve stems, pushrod tips and rocker arm pushrod sockets for any evidence of extreme pressure damage. That will tell you if it is possibly caused by improper pushrod length or valve spring installation.
Trojan Horse is offline   Reply With Quote
Old 08-21-2012, 10:47 PM   #20
Registered Member
Regular
 
Dadsgl67's Avatar
 
Join Date: Jul 2012
Region: California
Posts: 54
Quote:
Originally Posted by Trojan Horse
Ok, from what I can see I have more questions.

What heads are those?
Did you use a pushrod length checker to select the correct length pushrods?
Did you check the installed height of the valve springs?
What procedure did you use to adjust the valve lash?

Check the roller tips, valve stems, pushrod tips and rocker arm pushrod sockets for any evidence of extreme pressure damage. That will tell you if it is possibly caused by improper pushrod length or valve spring installation.
I have AFR heads on then I measured the length of pushrods I needed and used caps on the ends of the valve. I adjusted them 3 different ways 2 ways my teacher told me ad another a speed shop told me. There is no sign of extreme stress on these parts.

---------- Post added at 08:47 PM ---------- Previous post was at 08:43 PM ----------

Since I changed my studs they are not breaking ( knock on wood) but the nuts keep backing off!
Dadsgl67 is offline   Reply With Quote
Old 08-22-2012, 04:41 AM   #21
Road Trip!
Supporter
 
Join Date: Jun 2006
Region: Missouri
Posts: 8,779
Re: Broken rocker studs

Quote:
Originally Posted by Dadsgl67 View Post
I have AFR heads on then I measured the length of pushrods I needed and used caps on the ends of the valve. I adjusted them 3 different ways 2 ways my teacher told me ad another a speed shop told me. There is no sign of extreme stress on these parts.

---------- Post added at 08:47 PM ---------- Previous post was at 08:43 PM ----------

Since I changed my studs they are not breaking ( knock on wood) but the nuts keep backing off!
Did you look closely at the broken studs and see if they had any marks on them?
It is sounding like you just got a bad set of studs that were not properly heat treated.

Are you using poly-locks with the set screws in them? Those won't back off if properly set.
Trojan Horse is offline   Reply With Quote
Old 08-22-2012, 08:39 AM   #22
Registered Member
Regular
 
Dadsgl67's Avatar
 
Join Date: Jul 2012
Region: California
Posts: 54
I am using those and they are backing off. What is the proper procedure to set them?
Dadsgl67 is offline   Reply With Quote
Old 08-22-2012, 07:33 PM   #23
Road Trip!
Supporter
 
Join Date: Jun 2006
Region: Missouri
Posts: 8,779
Re: Broken rocker studs

Quote:
Originally Posted by Dadsgl67 View Post
I am using those and they are backing off. What is the proper procedure to set them?
I searched to see if there was a torque spec, but I could not find any.

Basically once you have the rocker arm/valve clearance adjusted using the Poly Lock nut, you tighten down the set screw inside it snugly to keep the nut from backing off. You do have to be careful and not over tighten the set screw or it will break the Poly Lock nut in half.
Trojan Horse is offline   Reply With Quote
Old 08-23-2012, 12:02 AM   #24
Registered Member
Regular
 
Dadsgl67's Avatar
 
Join Date: Jul 2012
Region: California
Posts: 54
That's what I'm doing. And there's no torque spec cuz these are different because the stud doest have the little seat to torque on it would just tighten to the head. I tighten it till the rod hardly spins then tighten the lock nut till it snugs to the stud then give the nut and locking but an 1/8 th of a turn to seat them.
Dadsgl67 is offline   Reply With Quote
Old 08-23-2012, 02:37 AM   #25
Road Trip!
Supporter
 
Join Date: Jun 2006
Region: Missouri
Posts: 8,779
Re: Broken rocker studs

Quote:
Originally Posted by Dadsgl67 View Post
That's what I'm doing. And there's no torque spec cuz these are different because the stud doest have the little seat to torque on it would just tighten to the head. I tighten it till the rod hardly spins then tighten the lock nut till it snugs to the stud then give the nut and locking but an 1/8 th of a turn to seat them.

Yes, I understand that those studs are non-shouldered and for adjustable rockers.
I was looking for a specific tightening torque for the poly lock set screws not the adjusting nuts.

I am assuming you have a hydraulic cam and the 1/8 turn is for lifter preload?

If you are turning the adjusting nut after the set screw has been tightened, then that might be the problem even though you are tightening the adjusting nut further.
Try completing the adjustment with the set screw loose, then hold the adjusting nut still and tighten the set screw down last. This will load or stretch the nut a bit and provide better clamping force to hold it in place.
Trojan Horse is offline   Reply With Quote
Old 08-23-2012, 07:52 AM   #26
Registered Member
Regular
 
Dadsgl67's Avatar
 
Join Date: Jul 2012
Region: California
Posts: 54
Gotcha. And I turn the nut and set screw at the same time the 1/8 o a turn
Dadsgl67 is offline   Reply With Quote
Old 08-23-2012, 08:39 AM   #27
Road Trip!
 
Join Date: Apr 2011
Region: Indiana
Posts: 8,044
Sorry to jump in. Trojan really knows more than me about this than me. But after you set the recommended preload on the adjusting nut. That's where it should stay. You will have to hold it with a wrench when you tighten the set screw so it stays. This meaning the set screw should be backed off when tightening the adjusting screw also.That's what trojan was trying to say I believe..
dreamstang is offline   Reply With Quote
Old 08-23-2012, 03:46 PM   #28
Road Trip!
Supporter
 
Join Date: Jun 2006
Region: Missouri
Posts: 8,779
Re: Broken rocker studs

Quote:
Originally Posted by Dadsgl67 View Post
Gotcha. And I turn the nut and set screw at the same time the 1/8 o a turn
No, go ahead and turn the nut, then hold it still and tighten the set screw.
That's what has always worked for me.
Trojan Horse is offline   Reply With Quote
Old 08-23-2012, 03:47 PM   #29
Road Trip!
Supporter
 
Join Date: Jun 2006
Region: Missouri
Posts: 8,779
Re: Broken rocker studs

Quote:
Originally Posted by dreamstang View Post
Sorry to jump in. Trojan really knows more than me about this than me. But after you set the recommended preload on the adjusting nut. That's where it should stay. You will have to hold it with a wrench when you tighten the set screw so it stays. This meaning the set screw should be backed off when tightening the adjusting screw also.That's what trojan was trying to say I believe..
Yes it is.
You jump in whenever and wherever. Your input is always appreciated.
Trojan Horse is offline   Reply With Quote
Old 08-23-2012, 04:01 PM   #30
Road Trip!
 
Join Date: Apr 2011
Region: Indiana
Posts: 8,044
Quote:
Originally Posted by Trojan Horse

Yes it is.
You jump in whenever and wherever. Your input is always appreciated.
Cool thanx. I just wasn't sure if she was understanding exactly. So sometimes it helps to hear it a different way.
dreamstang is offline   Reply With Quote
Old 08-23-2012, 04:09 PM   #31
Road Trip!
Supporter
 
Join Date: Jun 2006
Region: Missouri
Posts: 8,779
Re: Broken rocker studs

Quote:
Originally Posted by dreamstang View Post
Cool thanx. I just wasn't sure if she was understanding exactly. So sometimes it helps to hear it a different way.
I agree completely and I'm not the best at explaining things, just ask my wife about that.
Trojan Horse is offline   Reply With Quote
Old 08-23-2012, 04:12 PM   #32
Road Trip!
 
Join Date: Apr 2011
Region: Indiana
Posts: 8,044
Quote:
Originally Posted by Trojan Horse

I agree completely and I'm not the best at explaining things, just ask my wife about that.
Lol. I disagree though.
dreamstang is offline   Reply With Quote
Old 08-24-2012, 12:39 AM   #33
Registered Member
Regular
 
Dadsgl67's Avatar
 
Join Date: Jul 2012
Region: California
Posts: 54
Your both good at explaining I tryed em both ways actually and they still backed off. I used lock tight this time
Dadsgl67 is offline   Reply With Quote
Old 08-24-2012, 12:57 AM   #34
Road Trip!
Supporter
 
Join Date: Jun 2006
Region: Missouri
Posts: 8,779
Re: Broken rocker studs

If that didn't work then you must have some type of strange issue happening for some reason. Harmonics, parts mismatch, or something else. In all my years I have not ran across more than 2-3 poly lock set screws that wouldn't stay set and there was an easily discernible reason for it each time. I'm at a loss for what else the issue might be at this point.


Possibly the tops of the studs are not parallel to the set screw so the screw is not getting a full bite when it is tightened down?
Trojan Horse is offline   Reply With Quote
Old 08-24-2012, 03:23 PM   #35
Road Trip!
 
Join Date: Apr 2011
Region: Indiana
Posts: 8,044
I forgot it reply the earlier

Imo.. I think your not properly preloading the lifter.
How much preload did you put on the lifter?
Did you tighten them in the proper firing order?
dreamstang is offline   Reply With Quote
Reply

Lower Navigation
Go Back   Mustang Evolution > 4 Cylinder | V6 | Classic Mustangs || Tech and Talk > Classic Mustangs

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are Off


» Like Us On Facebook



01:46 PM


Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO 3.6.0

MustangEvolution.com is in no way associated with or endorsed by Ford Motor Company.