Roller cam and valve adjustment?
Spin the engine to TDC Compression stroke on #1. Adjust exhaust for 1,3,4,8 and intake of 1,2,5,7
Rotate one full turn (TDC Compression #6): adjust exhaust 2,5,6,7 and intake of 3,4,6,8
For some reason I believe that when I have the cylinder at TDC, the lifter to be adjusted is NOT on the very bottom of the lobe (fully closed) because after the adjustment (I tried 1/2 turn from zero lash the first time and then a whole turn the second time I adjusted them) because they are even noisier/looser then before I touched them.
Is it possible that the steel roller cam in the ZZ4 is somehow configured differently than other camshafts?
Disconnect Battery, Remove Park plugs , Do each cyl. one at a time. Example...Start with #1 Cylinder do intake & exhaust for #1 cylinder , then #3 Cylinder Int. & exh. , then #5, int. & exh. Until every cylinder is finished. This pattern is easiest. you watch each valve go through its cycles and by the second or third cylinder youll understand exactly where each lifter is on the cam.
Use a 1/2" drive and 5/8ths Socket on the Balancer Bolt to turn the engine clockwise.
To start ,just be confident that When a lifter goes just past TDC (just starts down) on the compression stroke, the Other lifter is on the Base Circle of the cam. Or 180 Deg. from the Cams Lobe . Ready to preload the lifter thats now on the Base circle. Initially set it to zero, that is when the pushrod first starts to resist. you can feel it with your fingers. Then Use the Manufacturers recomended turns to set the Preload. Usually its somewhere over 1/2 turn But you need to just do what the lifter vendor advises and you wont go wrong.
Make sense? if not, It should by the time your finished
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I don't see how it's possible to adjust both the intake and exhaust valve on the same cylinder without rotating the crankshaft in between because the lifter must be on the base circle to have the valve fully closed. Correct?
Did you use this method on your 383 and if so, does it have a roller cam?
Thanks.
Setting Valve Lash on Mechanical Cams
All the valves must be set individually and only when the lifter is properly located on the base circle of the lobe.
At this position the valve is closed and there is no lift taking place.
How will you know when the valve you are adjusting is in the proper position with the lifter on the base circle of the cam?
This can be accomplished by watching the movement of the valves.
1. When the engine is hot (at operating temperature) remove the valve covers and pick the cylinder that you are going to adjust.
2. Hand turn the engine in its normal direction of rotation while watching the exhaust valve on that particular cylinder. When the exhaust valve begins to open, stop and adjust that cylinder's intake valve. (Why? Because when the exhaust is just beginning to open, the intake lifter will be on the base circle of the lobe, so the intake is the one we can now adjust.)
3. Use a feeler gauge, set to the correct valve lash, and place it between the tip of the valve stem and rocker arm. Adjust until you arrive at the proper setting and lock the adjuster in place.
4. After the intake valve has been adjusted, continue to rotate the engine, watching that same intake valve. The intake valve will go to full lift and then begin to close. When the intake is almost closed, stop and adjust the exhaust valve on that particular cylinder. (Again, when we see the intake valve almost closed, we are sure that the exhaust lifter is on the base circle of the lobe.) Use the feeler gauge and follow the procedure described before in step 3.
5. Both valves on this cylinder are now adjusted, so move to your next cylinder and follow the same procedure again. In the future you may find shortcuts to this method, but it still remains the best way to do the job correctly.
Should this be performed with the engine warm or cold?
Thanks





If you are coming to the #1 compression stroke, then #6 will be in overlap, you can tell this because the exhaust valve will be closing and the intake will start to open, when they are equal ( on #6 ) you will be on TDC of the compression stroke on #1 and you can adjust both intake and exhaust valves on #1 This might sound a little confusing but try it and you will see it's not.
You can set all your valves on each cylinder this way by looking at their opposite \ corresponding cylinders. Or you can mark your balancer at 90 deg intervals or buy a cover that is marked at these intervals. Here is the way I look at the firing order to determine which set of valves are in overlap and which ones are at TDC of the compression stroke and can be adjusted.
1 8 4 3
6 5 7 2
For #1 you look at #6, #8 you look at the valves on #5 and so on
Warm engine for solid cams and it doesn't really matter on hydraulic cams
I don't see how it's possible to adjust both the intake and exhaust valve on the same cylinder without rotating the crankshaft in between because the lifter must be on the base circle to have the valve fully closed. Correct?
Did you use this method on your 383 and if so, does it have a roller cam?
Thanks.

.Yes , Same cyl. ,you turn the engine again to get the other lifter phased onto the base circle , set the Preload and lock it down ..use Kool nuts, they will never loosen. Then you Move to the next cylinder and do Both on that Cyl.
And yes I have a OE hydraulic Roller engine, uses the same size lifters as yours, But that doesnt matter, the Same procedure is used for adjusting all "Hydraulic" lifters.
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This is the procedure for adjusting solid lifters. I'm not sure if the ZZ4 has hydraulic or solids.
Looks like I repeated what was posted above...pays to read before posting...
So, this leaves me to try adjusting them while the engine is running.
The only tough part will be cutting out a center bolt valve cover for access to the adjusters.
I have never had an engine give me this much trouble from a simple valve adjustment... Maybe it's just because it's a roller cam... who knows.
Thanks very much for all the suggestions guys.
So, this leaves me to try adjusting them while the engine is running.
The only tough part will be cutting out a center bolt valve cover for access to the adjusters.
I have never had an engine give me this much trouble from a simple valve adjustment... Maybe it's just because it's a roller cam... who knows.
Thanks very much for all the suggestions guys.
For a solid roller GDaina has it right (just backwords as he states) and for a hydraulic just leave the valve cover off, cut a piece of cardboard to just fit in the lower lip of the head, start when warm...1 at a time, loosen until it ticks loud, tighten until it stops & then go 3/4 turn 1/4 at a time letting the lifter catch up between each quarter turn so it dosent kill. Then repeat until all are done. There will be some oil to clean up but should not be to bad.
Warmed up the engine, Loosened the rockers until they started clicking loudly and very slowly tightened them until they got quiet then gave them another 1/2 turn. It's now very quiet and running great.
Didn't lose a drop of oil either.
Thanks again for all your help guys!
Then I backed them off and adjusted them one at a time.
Started on the drivers side and then did the pass side.
Only had one cover off at a time.












