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 02-18-2012, 04:20 PM   #1
savatreatabvr
Registered User
 
savatreatabvr's Avatar
 
Join Date: Oct 2011
Location: phoenix, az
Posts: 508
BBC Valve Adjustment Question?

When I adjust my mid 70's BBC valve it runs good for a while then goes back to running the way it did before I did the adjustment! I know it means the 454 has high miles and things are a little worn out but what is it that's worn out? The cam, the lifters, what else can it be?
savatreatabvr is offline   Reply With Quote
Old 02-18-2012, 04:38 PM   #2
STOCKISH
Formerly- 1972SuperCheyenne
 
STOCKISH's Avatar
 
Join Date: Oct 2008
Location: Wake Forest NC
Posts: 5,782
Re: BBC Valve Adjustment Question?

How long does it take to start running bad again? Could be cam, lifters, rocker nuts backing off, etc...
__________________
--Josh

My Build Thread:http://67-72chevytrucks.com/vboard/s...d.php?t=799218

A good crossthread is better than Loctite any day.

Life is not about what you have, but who you have to share it with.
STOCKISH is offline   Reply With Quote
Old 02-18-2012, 04:47 PM   #3
savatreatabvr
Registered User
 
savatreatabvr's Avatar
 
Join Date: Oct 2011
Location: phoenix, az
Posts: 508
Re: BBC Valve Adjustment Question?

It takes 10 miles or so + or -, never thought about how long but I did notice that some of the rocker arm studs show more threads than others, shouldn't they all be about the same?

Quote:
Originally Posted by 1972SuperCheyenne View Post
How long does it take to start running bad again? Could be cam, lifters, rocker nuts backing off, etc...
savatreatabvr is offline   Reply With Quote
Old 02-18-2012, 04:50 PM   #4
savatreatabvr
Registered User
 
savatreatabvr's Avatar
 
Join Date: Oct 2011
Location: phoenix, az
Posts: 508
Re: BBC Valve Adjustment Question?

and some don't seem to make much of a difference in the way it runs while doing the running adjustment procedure!

Quote:
Originally Posted by savatreatabvr View Post
It takes 10 miles or so + or -, never thought about how long but I did notice that some of the rocker arm studs show more threads than others, shouldn't they all be about the same?
savatreatabvr is offline   Reply With Quote
Old 02-18-2012, 11:05 PM   #5
STOCKISH
Formerly- 1972SuperCheyenne
 
STOCKISH's Avatar
 
Join Date: Oct 2008
Location: Wake Forest NC
Posts: 5,782
Re: BBC Valve Adjustment Question?

There should be the same amount of threads showing. Sounds like the press in rocker arm studs are pulling out of the heads. Not all that uncommon. Time to upgrade to screw in studs! Fix it before something more catastrophic happens though.
__________________
--Josh

My Build Thread:http://67-72chevytrucks.com/vboard/s...d.php?t=799218

A good crossthread is better than Loctite any day.

Life is not about what you have, but who you have to share it with.
STOCKISH is offline   Reply With Quote
Old 02-19-2012, 12:45 AM   #6
74 stepside
Registered User
 
74 stepside's Avatar
 
Join Date: Oct 2009
Location: SoCal
Posts: 815
Re: BBC Valve Adjustment Question?

BBC have screw in studs. Its the SBC that have pressed in studs. Sounds like your hydrolic lifters that might be causing your problem.
74 stepside 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 03:45 PM.


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