The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1973 - 1987 Chevrolet & GMC Squarebody Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 03-12-2024, 09:28 PM   #1
willem445
Registered User
 
willem445's Avatar
 
Join Date: Jun 2013
Location: N/A
Posts: 238
Need advice on rocker arms!

Hi all, latest project was replacing valve covers and oil pan to hopefully stop the leaks. In the process of cleaning up head for the new valve cover, I noticed 2 chunks of metal sitting in the head. Pulled them out and narrowed it down to one of the rocker arms breaking. I pulled the oil pan first and did not find any chunks or even metal shavings in oil.

Couple pictures:







I'm not very knowledgable yet when it comes to repairing engine internals. From what I've read, it's good to just replace all the rocker arms and pushrods while the covers are off.

Any recommendations for rocker arms? Just go with stock or upgrade? I found these on Summit.
What about pushrods?
Any advice for replacing the arms and pushrods? This will be my first time.
__________________
The square family:
1980 Chevy K20 Farm Truck
1977 Chevy K20
1986 Chevy K30 3+3 Dually
willem445 is offline   Reply With Quote
Old 03-12-2024, 09:46 PM   #2
willem445
Registered User
 
willem445's Avatar
 
Join Date: Jun 2013
Location: N/A
Posts: 238
Re: Need advice on rocker arms!

Also what about rocker arm ratio? My Dad said this 350 had a cam put in it but no clue what cam. Is there a way I can measure what ratio the existing rockers are?
__________________
The square family:
1980 Chevy K20 Farm Truck
1977 Chevy K20
1986 Chevy K30 3+3 Dually
willem445 is offline   Reply With Quote
Old 03-12-2024, 09:56 PM   #3
Dead Parrot
Registered User
 
Join Date: Aug 2012
Location: Oklahoma City, OK
Posts: 2,583
Re: Need advice on rocker arms!

Others may disagree, but for a stock or mostly stock motor, just replace the bad rocker and push rod.

Make sure the valve isn't stuck. I had a valve stick open and the push rod bent. Could be you have one stuck and the rocker is what gave. My motor was stock and I had a spare stock head off of a motor for a project that didn't happen, so fixed it by just swapping the one head.

If you are worried about metal bits, cut open the old oil filter and check with a magnet.
Dead Parrot is offline   Reply With Quote
Old 03-13-2024, 01:09 PM   #4
72malibu
Active Member
 
72malibu's Avatar
 
Join Date: Jun 2019
Location: Gaithersburg, MD
Posts: 122
Re: Need advice on rocker arms!

Consider asking over on Team Chevelle site. There are very many engine experts over there, including the moderator of the engine section. (I'm not saying there aren't experts here -- I just don't have that familiarity with this site as I do Team Chevelle). One of those guys built the 350 in my profile pic.
72malibu is offline   Reply With Quote
Old 03-14-2024, 12:06 PM   #5
kwmech
Senior Member
 
Join Date: Mar 2003
Location: Colfax-California
Posts: 8,592
Re: Need advice on rocker arms!

I'd replace just the one--push rod, arm and pivot and readjust and run it. See what happens before you waste a bunch of money.
kwmech is offline   Reply With Quote
Old 03-14-2024, 02:09 PM   #6
MySons68C20
Senior Member
 
MySons68C20's Avatar
 
Join Date: Sep 2014
Location: Wenatchee, Wa
Posts: 922
Re: Need advice on rocker arms!

Quote:
Originally Posted by kwmech View Post
I'd replace just the one--push rod, arm and pivot and readjust and run it. See what happens before you waste a bunch of money.
^^^^^^^^^^^^^^best advice here
MySons68C20 is online now   Reply With Quote
Old 03-15-2024, 03:25 PM   #7
truckin 79
Registered User
 
Join Date: Jun 2014
Location: CO
Posts: 745
Re: Need advice on rocker arms!

I am no expert but I have messed with a few small block chebbies. You could just replace rocker but I would definitely rotate engine a few times at crank bolt with a ratchet. I would watch and make sure the rockers are not hitting the front of the rocker stud. I have never seen one just crack in front of rocker like that. I have seen them split in half before from over tightening. Check the push rod for any marring or other damage. Roll it on a flat surface to make sure it is not bent and you could probably still use it
__________________
79 Chevy 2wd BIG10 350 TH400
truckin 79 is offline   Reply With Quote
Reply

Bookmarks


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

Forum Jump


All times are GMT -4. The time now is 07:18 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com