valve adjustment
Tech Contributor
Joined: Aug 1999
Posts: 15,130
Likes: 3,938
From: Connecticut, USA
There are several ways to do it, I like the procedure Lars wrote up years ago. Start with #1 cyl at TDC adjust them and follow the firing order by moving the crank in 90* increments. Mark the balancer with caulk so you know where you have to stop when turning.
Le Mans Master
Joined: Jun 2004
Posts: 6,231
Likes: 65
From: Seattle WA
St. Jude Donor '14
There is some level of debate regarding this technique, but for the last 5 years or so I've been using the companion cylinder method and it's been fast and perfect. It does require a VERIFIED TDC indicator.
http://www.carcraft.com/howto/ccrp_0...aft/index.html
http://www.carcraft.com/howto/ccrp_0...aft/index.html
Drifting
Joined: Oct 2007
Posts: 1,317
Likes: 22
From: Marina CA
I have used this method for many years on the other 427 and it was foolproof. Once true TDC was known the balancer was marked every 90 degrees.
Le Mans Master
Joined: Jun 2004
Posts: 6,231
Likes: 65
From: Seattle WA
St. Jude Donor '14
Drifting
Joined: Dec 2002
Posts: 1,946
Likes: 28
From: Long Beach CA
With #1 at TDC on the compression stroke, adjust:
exhaust valves on #1, #3, #4, and #8.
intake valves on #1, #2, #5, and #7.
Turn the crank 360* so #6 is at TDC on the compression stroke, and adjust:
exhaust valves on #2, #5, #6, and #7.
intake valves on #3, #4, #6, and #8.
exhaust valves on #1, #3, #4, and #8.
intake valves on #1, #2, #5, and #7.
Turn the crank 360* so #6 is at TDC on the compression stroke, and adjust:
exhaust valves on #2, #5, #6, and #7.
intake valves on #3, #4, #6, and #8.
Drifting
Joined: Nov 2002
Posts: 1,676
Likes: 197
From: Loveland, CO
I like the method whereby the motor is running and oil is squirting in eight narrow streams over the fenders. That's the method I just used on my '73 BB. Since I had installed Comp Cams Magnum roller rockers, the standard clip on squirter stoppers didn't stay on the rocker arms. Now, I notice in the catalogs for these parts that they say they only work on stock rocker arms. Now, they tell me. I think I only used about a quart of oil for each cylinder bank, and then cleaned everything up for days.
This is my preferred method.
Ralph.
This is my preferred method.
Ralph.
Last edited by rponfick; Nov 6, 2008 at 09:30 PM.
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Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
Little messy, but do them running. Back off one at a time until it rattles, tighten it up until it just quits, then go another 1/4 turn. do one side at time and it's less messy unless you're really fast, and park in the grass so you don't oil the driveway.
The GM service manual has a procedure to set them without it running, (I think it's the one LB66383 posted), but it really takes a "feel" to get it right, and you'll be leaving some performance on the table.
The GM service manual has a procedure to set them without it running, (I think it's the one LB66383 posted), but it really takes a "feel" to get it right, and you'll be leaving some performance on the table.
Burning Brakes
Joined: Aug 2007
Posts: 892
Likes: 243
From: Green Valley Ca
Intermediate
Joined: Jul 2008
Posts: 40
Likes: 0
I was about to do the same for my 72, and I am still a bit conflicted about which technique is the best.
My Dad, and friends who are ASE certified like and was taught adjust hydraulic valves hot, and while the engine is running. They either used these oil clips that attach to the rocker arms or a chopped up valve cover.
I was originally going to do it hot with the engine on, but the oil clips that my Dad had only fits stock rocker arms and I have 1.52 Comp cam roller rockers.
So, after doing some research, I founds Lars document, and the one from Comp Cams recommend doing it cold. My friends also warned me about adjusting cold, because if I do it wrong I can flatten my cams
But after seeing this video on Youtube, I feel more comfortable do the valve job myself.
http://www.youtube.com/watch?v=89o5rLpbCgI
My Dad, and friends who are ASE certified like and was taught adjust hydraulic valves hot, and while the engine is running. They either used these oil clips that attach to the rocker arms or a chopped up valve cover.
I was originally going to do it hot with the engine on, but the oil clips that my Dad had only fits stock rocker arms and I have 1.52 Comp cam roller rockers.
So, after doing some research, I founds Lars document, and the one from Comp Cams recommend doing it cold. My friends also warned me about adjusting cold, because if I do it wrong I can flatten my cams
But after seeing this video on Youtube, I feel more comfortable do the valve job myself.
http://www.youtube.com/watch?v=89o5rLpbCgI
Melting Slicks
Joined: Apr 2008
Posts: 2,621
Likes: 242
From: Russell Ontario
St. Jude Donor '09
I've done them engine running and stopped , ether way is easy nobody mentioned a cut out valve cover to adjust them , that way you can take your time and no mess , just have the idle turned down a little . Ron
Drifting
Joined: Nov 2002
Posts: 1,676
Likes: 197
From: Loveland, CO
The cut down valve cover only works if you have low oil pressure and the oil just dribbles out the rocker holes. Mine squirted over the fenders, and I was using a cut out valve cover. I finally trimmed the stock clip-on deflectors so they would fit on the comp cams rockers. After that episode, I see Northern Auto sells a different version that plugs into the oil hole and temporarily stops the flow. At least that is what they are supposed to do since I haven't tried them yet.
Ralph
Ralph
Burning Brakes
Joined: Dec 2007
Posts: 952
Likes: 0
The cut down valve cover only works if you have low oil pressure and the oil just dribbles out the rocker holes. Mine squirted over the fenders, and I was using a cut out valve cover. I finally trimmed the stock clip-on deflectors so they would fit on the comp cams rockers. After that episode, I see Northern Auto sells a different version that plugs into the oil hole and temporarily stops the flow. At least that is what they are supposed to do since I haven't tried them yet.
Ralph
Ralph
