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Discussion Starter #1
First some background:
Freshly rebuilt 305. Bored 30 over with flat top pistons, 416 heads, and .035" head gaskets. Edelbrock Performer 2102 cam and lifters, Performer intake, Holley 80570 (570 cfm) carb, HEI distributor, stock exhaust manifolds with full duals, no cats. Comp Cams High Energy Die Cast Aluminum Roller Rocker Arms with 1.5 ratio.

Engine was broken in at 2000 and 2500 RPM with ZDDP added to the oil. Then the oil and filter were changed (with another bottle of ZDDP) and the car ('80 El Camino) was driven around the block.

The engine was running a little rough, with no "get up and go". Idled about 800 RPM. Messed with the timing to get the best idle I could get. Set float levels in both bowls. Fuel pressure was pulsing around 5- 8 psi with a new stock fuel pump.

I had adjusted the valves during the build according to what Edelbrock stated:

"With #1 cylinder at TDC firing position, adjust exhaust valves on cylinder numbers 1, 3, 4, 8 and intake valves on cylinder numbers 1, 2, 5, 7 as follows: You need to set rockers at zero lash. While tightening the rocker nut, spin the pushrod, when you feel resistance, you are at zero lash. Tighten rocker nut half turn past zero lash. NOTE: If rocker nut has no pressure feel while tightening, replace with new nuts supplied. Nuts must have a locking feel to them.

Turn engine one complete revolution so #6 cylinder is at TDC firing position and adjust exhaust valves on cylinder numbers 2, 5, 6, 7 and intake valves on cylinders 3, 4, 6, 8 in the same manner. The valves are now adjusted."

That differs from what I had done years ago when I built SBCs. I had adjusted the rocker until the pushrod could not be rotated at all and then tightened the rocker a half turn. Slight difference in method, but maybe not significant?

So I decided I'd check the adjustment again. I pulled the spark plugs, wires, and valve covers. Set #1 at TDC on firing stroke and checked the lash. Many of them seemed out of adjustment - either too tight or too loose so I adjusted them the "old" way - until the pushrod could not be rotated at all and then tightened the rocker a half turn. A couple of the rockers got tight and would not tighten any more. It was like the lifter had bottomed out. Repeated for TDC at #6.

Put everything back together, verified plug wires went to proper plugs, and tried to start it. It ran like it was terribly out of time, would not idle, and sounded like a rattle-trap. The distributor had never been moved but I tried turning it either direction to make it run. No luck.

Because a couple of the rockers had gotten tight and would not tighten any more during the adjustment I think maybe the lifters had collapsed. It was like the lifters had bottomed out.

Now I'm wondering what to do. I thought about pulling the plugs and valve covers and backing off all the rockers to see if the lifters will pump back up, then readjusting the lash. How can I get the lifters to pump back up? Don't they have internal springs that will "pump them up"? I hesitate to turn the engine over with all the valves closed but I need to see if a lifter or two is bad.

Ideas?

Jack
 

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{ so I adjusted them the "old" way - until the pushrod could not be rotated at all and then tightened the rocker a half turn. A couple of the rockers got tight and would not tighten any more.}
Are you saying that after tightening all the way, some rods were still loose?
And I guess you replaced the nuts with the new ones supplied?
Donny
 

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man thats a tough one... if it was mine i would pull all spark plugs pull dizzy and reprime oiling system back off all rockers turn over motor a few times BY HAND ensure you have oil pressure readjust valves and see if they pumped up if not looks like a bad lifter or lifters??
:beer::dontknow::secret:
 

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you make sure the cam is at the bottom of the lobe, the way I do it,, going off my memory,, the intake valve starts to open just about a 1/4 way the exhaust is at the bottom of the lobe,, after adjustment rotate until the exhaust is at full open then just starts to go down,, adjust the intake now it is at the bottom of the lobe,, when you adjust the valve, loose push rod, tighten to just no rotation of the push rod and 1/2 turn,, someone verify this is correct,, I dont have a cam sitting in front of me to double check my old memory,,, Matty man
 

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Compression stroke is just after intake closes on no. 1 cylinder and timing mark is at tdc. Adjust as matty man described. Try a quarter turn instead of a half and readjust after the motor is warm and still running. Good luck.
 

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suggest you re-read the manual that came with the cam,I don't recall having to pump mine up, as they have an internal spring.
 

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Discussion Starter #8
{ so I adjusted them the "old" way - until the pushrod could not be rotated at all and then tightened the rocker a half turn. A couple of the rockers got tight and would not tighten any more.}
Are you saying that after tightening all the way, some rods were still loose?
And I guess you replaced the nuts with the new ones supplied?

Donny
Are you saying that after tightening all the way, some rods were still loose?
No. The puhrods were tight

And I guess you replaced the nuts with the new ones supplied?
Yes. They're the ones with the Allen head screw to adjust and a 5/8" nut to lock.
 

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Here's my easy way:

G M Valve lash Adjustment
1. Remove the rocker covers and gaskets.
2. Crank the engine untill the mark on the damper aligns with the TDC or 0 mark on the timing tab and the engine is in the No. 1 firing position. This can be determined by placing your finger on the No. 1 cylinder valves as the marks align. If the valves do not move, it is in the No. 1 firing position. If the valves do move, it is in the No.6 firing position (No. 4 on the V6) and the crankshaft should be rotated 1 more revolution to the No. 1 firing position. To adjust a valve, back off the adjusting nut untill lash (play) is felt at the pushrod. Tighten the nut just untill all lash is removed. This can be determined by rotating the pushrod with your fingers. When all lash is removed the pushrod will stop rotating. When all play is removed, tighten the nut 1 full turn (360 degrees).
3. With the engine in the No. 1 firing position, the following valves can be adjusted:
V6 ENGINES

Exhaust - 1,5,6
Intake - 1,2,3

V8 Engines
Exhaust - 1,3,4,8
Intake - 1,2,5,7
4. Crank the engine 1 full revolution untill the marks are again in alignment. This is the No. 6 firing position (No. 4 on the V6). The following valves can now be adjusted:
V6 ENGINES

Exhaust - 2,3,4
Intake - 4,5,6

V8 Engines
Exhaust - 2,5,6,7
Intake - 3,4,6,8
5. Reinstall the rocker arm covers using new gaskets.

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This will get you close enough for the engine to run, at least. Mine were set this way originally (on my hot rod). After I got it running pretty well, I built a valve cover with a slot in it and a deflector to keep oil from spraying around and did it the old fashioned way with the engine running: Slowly loosen the rocker adjusting nut until you hear it tapping. Gently tighten it until it quits tapping, then go 1/4 turn more. Did a friend's hot rod yesterday; using the static method, he had some so tight the valves weren't closing. When you back off an adjusting nut and the engine suddenly smooths out, it was wayyyyy to tight!
 

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Discussion Starter #11
Here's my easy way:

G M Valve lash Adjustment
1. Remove the rocker covers and gaskets.
2. Crank the engine untill the mark on the damper aligns with the TDC or 0 mark on the timing tab and the engine is in the No. 1 firing position. This can be determined by placing your finger on the No. 1 cylinder valves as the marks align. If the valves do not move, it is in the No. 1 firing position. If the valves do move, it is in the No.6 firing position (No. 4 on the V6) and the crankshaft should be rotated 1 more revolution to the No. 1 firing position. To adjust a valve, back off the adjusting nut untill lash (play) is felt at the pushrod. Tighten the nut just untill all lash is removed. This can be determined by rotating the pushrod with your fingers. When all lash is removed the pushrod will stop rotating. When all play is removed, tighten the nut 1 full turn (360 degrees).
3. With the engine in the No. 1 firing position, the following valves can be adjusted:
V6 ENGINES

Exhaust - 1,5,6
Intake - 1,2,3

V8 Engines
Exhaust - 1,3,4,8
Intake - 1,2,5,7
4. Crank the engine 1 full revolution untill the marks are again in alignment. This is the No. 6 firing position (No. 4 on the V6). The following valves can now be adjusted:
V6 ENGINES

Exhaust - 2,3,4
Intake - 4,5,6

V8 Engines
Exhaust - 2,5,6,7
Intake - 3,4,6,8
5. Reinstall the rocker arm covers using new gaskets.

--------------------------------------

This will get you close enough for the engine to run, at least. Mine were set this way originally (on my hot rod). After I got it running pretty well, I built a valve cover with a slot in it and a deflector to keep oil from spraying around and did it the old fashioned way with the engine running: Slowly loosen the rocker adjusting nut until you hear it tapping. Gently tighten it until it quits tapping, then go 1/4 turn more. Did a friend's hot rod yesterday; using the static method, he had some so tight the valves weren't closing. When you back off an adjusting nut and the engine suddenly smooths out, it was wayyyyy to tight!
Thanks, but I guess you didn't read my post closely??
 

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There are deflectors to use to keep from spraying the oil with the engine running and the covers removed. They cost between $10-20 for a set of eight. Ya only do one side at a time.:nanawrench:
 

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Discussion Starter #13
I think I've figured out what to do.

I'll back off all the rockers until the valves are all seated and the lifters are relieved off any pressure. Then I'll pull the distributor and spin the oil pump to build up pressure. That should cause all the lifters to pump up. Then I can adjust the lash again.

Any other ideas?
 

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Discussion Starter #15
I appreciate everyone telling me to adjust the valves, but that isn't the question. The question refers to a couple of the lifters seeming to have bottomed out and how can I pump them all back up so I can, once again, adjust the lash. My post #13 is my idea of how to do that.
 

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Jack, my guess without seeing the motor is the lifters were not on base circle when the valves were adjusted,, if a lifter was bottomed out, with no more adjustment,, there is internal damge to the lifter. I have to say I did the same thing to a 355 with Edelbrock heads and performer RPM cam,, I did not adjust the valve correctly,, they clacked and noisy,, I thought I had done it the way the "book" said to,, thats when my racin` engine builder taught me the way I stated before,, so what would I do from here myself?? I would most likely do what you said, re adjust the valve and prime it and see if oil comes up and does not bleed back down,, after my 355 ordeal I have used the 1 valve at time,, and never had any issues and never touched the valves again on the hyd cam,, Let us know how the new adjustment & prime goes,, Matty man
 

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when they say "no play" they don't mean that you can't turn the push rod. They mean that as you adjust the rocker down keep wiggling it up and down until there is no play between it and the push rod. this can be tricky on a new set of lifters because the little spring in the lifter is all you have to go against. DO NOT BOTTOM the lifter plunger while adjusting.
 

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Fine if you have a stock cam

Here's my easy way:

G M Valve lash Adjustment
1. Remove the rocker covers and gaskets.
2. Crank the engine untill the mark on the damper aligns with the TDC or 0 mark on the timing tab and the engine is in the No. 1 firing position. This can be determined by placing your finger on the No. 1 cylinder valves as the marks align. If the valves do not move, it is in the No. 1 firing position. If the valves do move, it is in the No.6 firing position (No. 4 on the V6) and the crankshaft should be rotated 1 more revolution to the No. 1 firing position. To adjust a valve, back off the adjusting nut untill lash (play) is felt at the pushrod. Tighten the nut just untill all lash is removed. This can be determined by rotating the pushrod with your fingers. When all lash is removed the pushrod will stop rotating. When all play is removed, tighten the nut 1 full turn (360 degrees).
3. With the engine in the No. 1 firing position, the following valves can be adjusted:
V6 ENGINES

Exhaust - 1,5,6
Intake - 1,2,3

V8 Engines
Exhaust - 1,3,4,8
Intake - 1,2,5,7
4. Crank the engine 1 full revolution untill the marks are again in alignment. This is the No. 6 firing position (No. 4 on the V6). The following valves can now be adjusted:
V6 ENGINES

Exhaust - 2,3,4
Intake - 4,5,6

V8 Engines
Exhaust - 2,5,6,7
Intake - 3,4,6,8
5. Reinstall the rocker arm covers using new gaskets.

--------------------------------------

This will get you close enough for the engine to run, at least. Mine were set this way originally (on my hot rod). After I got it running pretty well, I built a valve cover with a slot in it and a deflector to keep oil from spraying around and did it the old fashioned way with the engine running: Slowly loosen the rocker adjusting nut until you hear it tapping. Gently tighten it until it quits tapping, then go 1/4 turn more. Did a friend's hot rod yesterday; using the static method, he had some so tight the valves weren't closing. When you back off an adjusting nut and the engine suddenly smooths out, it was wayyyyy to tight!

This way is fine IF you have a stock valve train and cam,you do not, i would do it the way the link said that i sent you...only did my first cam 34 years back inHS
 

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Discussion Starter #19
This way is fine IF you have a stock valve train and cam,you do not, i would do it the way the link said that i sent you...only did my first cam 34 years back inHS
Thanks, but that was not my post. It was by mrblanche.
 

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Discussion Starter #20
man thats a tough one... if it was mine i would pull all spark plugs pull dizzy and reprime oiling system back off all rockers turn over motor a few times BY HAND ensure you have oil pressure readjust valves and see if they pumped up if not looks like a bad lifter or lifters??
:beer::dontknow::secret:
Motor is too tight to turn by hand. Of course the plugs are out, but all the belts are tight.
 
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