Register or Log In To remove these advertisements. |
|
|
|
Thread Tools | Display Modes |
05-14-2019, 05:31 AM | #1 |
Registered User
Join Date: Sep 2014
Location: Warwick , Warwickshire, England
Posts: 79
|
Rocker Arm Stud needs repacing ?
Took the truck out at the weekend and it started knocking, Found the problem when I got home. When I took the rocker cover off one in the rockers was sitting at an angle, Pulled it apart and found this
The rocker stud has a deep grove worn into it and the top of the valve stem is pitted. I plan to replace the push rod, rocker stud and fit a new rocker kit. Questions 1, What's the easiest way to replace the rocker stud ? I've seen some videos with screw in studs but can that be done safely with the head still in the truck (I really don't want to have to take the head off if I don't have to) Question 2, Will the valve stem top be ok as is or should I try to smooth and polish it ? |
05-14-2019, 05:55 AM | #2 |
Registered User
Join Date: Oct 2013
Location: Maine
Posts: 2,358
|
Re: Rocker Arm Stud needs repacing ?
The stud still has a lot of strength left. I would put on a new rocker and send it. The other option is to remove the head and fix everything properly. That will snowball into all new valves and all new rockers and a valve job.
__________________
76 Chevy K20 76 GMC K15 77 Chevy C10 77 Chevy K10 |
05-14-2019, 09:21 AM | #3 |
Registered User
Join Date: Aug 2009
Location: Bowser
Posts: 13,657
|
Re: Rocker Arm Stud needs repacing ?
Choices!
Be cheap and tap the stud back in and pin it, clean the valve stem head, new rocker, set it up, run it. And then wait for the wrong time for it all to come apart again. And maybe not that one either. If one pulled out, others could. Could have a lot more damage. Or pop off both heads and rebuild or replace them. Considering where you live it might be better to replace them. |
05-14-2019, 11:47 AM | #4 | |
Registered User
Join Date: Sep 2014
Location: Warwick , Warwickshire, England
Posts: 79
|
Re: Rocker Arm Stud needs repacing ?
Quote:
|
|
05-14-2019, 12:09 PM | #5 |
Registered User
Join Date: Mar 2005
Location: Jurupa Valley, Ca
Posts: 1,210
|
Re: Rocker Arm Stud needs repacing ?
I had a stud pull up on a 307 in a boat years ago. Just put the new stud in the freezer overnight, heated the head with a propane torch and tapped the new one in. Ran the boat for a couple of years after with no issues at all. I would replace it with a new one.
__________________
Terry 1970 Custom Camper/C20 , GM Crate 350/7004R, Dana 60, factory AC |
05-14-2019, 12:17 PM | #6 |
Registered User
Join Date: Aug 2009
Location: Bowser
Posts: 13,657
|
Re: Rocker Arm Stud needs repacing ?
|
05-14-2019, 06:49 PM | #7 |
Senior Member
Join Date: Feb 2012
Location: chillicothe, illinois
Posts: 690
|
Re: Rocker Arm Stud needs repacing ?
The valve tip is hardened so it can be resurfaced when a valve job is done. the valve tip is damaged beyond the hardened part and if you put a rocker on that valve you are asking for trouble and valve train failure.
|
05-14-2019, 07:06 PM | #8 |
Senior Member
Join Date: Dec 2011
Location: Moraga, CA
Posts: 812
|
Re: Rocker Arm Stud needs repacing ?
Classic textbook failure. The books show using a stack of washers and a nut to pull out the old one. Then tapping the hole for a new screw-in one. Just make sure you get the tap straight.
Disclaimer: I've never had one fail in that way myself (but have seen it many times in many books), and I currently have heads with screw-in studs. So take my comments with a grain of salt.
__________________
(Very) Slow-Going Build Thread: Stock 1970 Short Step with Stock 1970 LT-1 http://67-72chevytrucks.com/vboard/s...d.php?t=567340 |
05-14-2019, 11:23 PM | #9 |
60-66 Nut
Join Date: Mar 2007
Location: Coeur d'Alene, Idaho
Posts: 23,248
|
Re: Rocker Arm Stud needs repacing ?
Without replacing that valve, another rocker will not sit right and this will likely happen again.
__________________
Power Steering Box Adapter Plates For Sale HERE Power Brake Booster Adapter Brackets For Sale '63-'66 HERE and '67-'72 HERE and '60-'62 HERE and "60-'62 with clutch HERE Rear Disc Brake Brackets For Sale. Impala SS calipers HERE Camaro Calipers HERE D52 Calipers HERE 6 Lug HERE Hydroboost Mounting Plates HERE |
05-15-2019, 12:35 AM | #10 |
Senior Member
Join Date: Mar 2003
Location: Colfax-California
Posts: 8,569
|
Re: Rocker Arm Stud needs repacing ?
BEFORE you pull the stud, drain the cooling system a little. Hole goes through to the cooling system.
|
05-15-2019, 01:15 AM | #11 |
Senior Member
Join Date: Sep 2005
Location: Lewisville, Nc
Posts: 10,236
|
Re: Rocker Arm Stud needs repacing ?
At these point a proper repair would be to pull the head and replace the vavle and has all new screw in studs put in
__________________
David fuller Ase Certified Mechanic Click here to help support our board!! 1971 Chevy c-10 under going a 4.8l LSx swap Build Thread http://67-72chevytrucks.com/vboard/s...d.php?t=421305 2007 Honda Accord my daily 145kmiles 2002 Honda Accord 4 door With 330k(sisters car) 2005 toyota Avalon 228k( brothers car) 2002 Sububran 5.3 245k 2000 Tahoe 5.3l 378 General manager for Marco's Carwash & lube |
05-16-2019, 07:50 AM | #12 |
Registered User
Join Date: Sep 2014
Location: Warwick , Warwickshire, England
Posts: 79
|
Re: Rocker Arm Stud needs repacing ?
How do I work out which size screw in stud I need ?
|
05-16-2019, 08:44 AM | #13 |
Registered User
Join Date: Aug 2009
Location: Bowser
Posts: 13,657
|
Re: Rocker Arm Stud needs repacing ?
What are you planning to do?
Replace the bad one or all of them. If it’s likely just that one then you don’t need a screw in stud. A new press in one that’s pinned will work. Did you check to see if that one is pulled out? Stud size depends on your spring pressure. Higher pressure needs bigger studs. Last edited by geezer#99; 05-16-2019 at 08:55 AM. |
05-16-2019, 11:59 AM | #14 |
Senior Member
Join Date: Jan 2011
Location: Hayes Va
Posts: 4,569
|
Re: Rocker Arm Stud needs repacing ?
First thing is you need to decide how long you need the repair to last. Less than a month, pull that stud and drive one in the hole and throw a new rocker on it. More than a month pull the heads and have them done. That valve tip is beat to pieces and will eat a rocker in short order based on my past experiences. The valve tip is what keep the rocker sitting correctly in the stud. When it gets rounded off the rocker leans to one side and begins to eat the side of the stud giving you what you have now. In my 40 + years of working on motors I have had to patch a few to get work in the morning or carry me till payday. Always hoping to have it last till I could fix it correctly.
Jimmy
__________________
60 to 66 Chevy and GMC window decals http://67-72chevytrucks.com/vboard/s...d.php?t=661131 Good friends, good food and a hotrod what else do you need? 1966 BBW long fleet Daily driver 1965 BBW short fleet Sold and going to a good home 1965 Suburban 2003 3500 Duramax 2005 Ultra Classic |
05-16-2019, 03:21 PM | #15 | |
Registered User
Join Date: Sep 2014
Location: Warwick , Warwickshire, England
Posts: 79
|
Re: Rocker Arm Stud needs repacing ?
Quote:
|
|
05-16-2019, 11:25 PM | #16 |
60-66 Nut
Join Date: Mar 2007
Location: Coeur d'Alene, Idaho
Posts: 23,248
|
Re: Rocker Arm Stud needs repacing ?
Yes, if you want it to last any length of time. With a stock engine, there is no need for screw in studs.
If you happen to be close to Stonnall, Staffordshire, there is someone there that I know that could help you.
__________________
Power Steering Box Adapter Plates For Sale HERE Power Brake Booster Adapter Brackets For Sale '63-'66 HERE and '67-'72 HERE and '60-'62 HERE and "60-'62 with clutch HERE Rear Disc Brake Brackets For Sale. Impala SS calipers HERE Camaro Calipers HERE D52 Calipers HERE 6 Lug HERE Hydroboost Mounting Plates HERE |
05-17-2019, 07:27 PM | #17 |
Registered User
Join Date: Dec 1999
Location: Austin, TX, USA
Posts: 7,722
|
Re: Rocker Arm Stud needs repacing ?
I had a set of heads that I put on my Jimmy that had one stud put in a little crooked and the rocker didn't sit square on the valve. I added a lash cap to that one valve stem and have been running it 30 years that way.
Google lash cap and see how they are used. You can buy screw in studs that don't have the hex on them. So stack some rocker pivot balls up on the pressed in stud and tighten a rocker nut down to pull the stud. Tap the hole and screw the stud in. Add lash cap to valve stem after cleaning it up and run it for as long as it goes.
__________________
44 Willys MB 52 M38A1 64 Corvette Coupe 68 Camaro 'vert LT1 & TH700 69 Z/28 355 12.6's @110 69 Chevy Short Step 4 1/2"/7" drop 72 Jimmy 4WD 4spd 4" & 35's 02 GMC 2500HD 4x4 Duramax |
Bookmarks |
|
|