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Discussion Starter #1
Did a good search and found bits of info I needed, but still have a question.
Hydraulic lifters and valve lash. I understand to tighten down until 0 lash then 1/4 to 1/2 turn more. But you do this when the lifter is not lifting right? when its sitting flat in the lifter bore?
 

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i've always set them "hot" when the car is up to temperature and with the motor running at an idle.*****WARNING****-VERY MESSY PROCESS!!
to reduce the mess,tear off several small pieces of tinfoil(approx 3 inches square) and squish this around the rocker end on the pushrod side to work as an oil catcher/deflector.squish them good,because the rocker will be flipping back and forth like crazy and you don't want the foil coming off midway through the job.
back off the rocker nut (one at a time ONLY) until the rocker arm starts "clacking". tighten down slowly until the clacking stops and then turn 1/4 turn SLOWLY. after 15 seconds,turn it down another 1/4 turn SLOWLY AGAIN.the "slow" part allows the hydraulic lifter to bleed down and you'll notice the valave may hang up (in effect,you've created too much lift for a brief time if you crank it down too fast) and cause the engine to stumble for a few seconds.don't worry if this happens,just slow down on the tightening as you proceed.
BE PREPARED BEFORE YOU START.tools handy,rags,tinfoil on and THEN begin.as stated before,this is a messy process and may best be performed outside.oil will drip onto hot exhaust manifolds and it'll look like your car's on fire.:eek::D
please remember that i'm not a master mechanic,but this process has worked for me over the years.i usually will preload(after 0 lash) a maximum of 5/8ths to 3/4s of a turn.anymore than that and it indicates that you've got bigger problems than a pushrod adjustment.
please chime in if you can add anything to these statements.
leftcoast carl.
 

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I dont like to set the valve lash while the motor is running, you just dont know how much preload is on the lifters. The cam manufactures invested a lot of time and money in their products so I run what they recommend. If they call for 1/2 turn with their lifters, that's what Ill use.

Yes, when you adjust the valve lash, you want the lifter to be on the base of the camshaft. Otherwise it will be on the lift part of the camshaft and may be too loose.

I have a method I was wondering if it will work well. Could you use a dial indicator to find the max lift point of the camshaft, then turn the crank 1 revolution (180 degrees on the camshaft) then adjust the valve lash to spec? This would insure you are not on the lift portion of the camshaft so you have the proper pre-load. Maybe that's to much work though.

-Dan
 

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I adjusted mine 1/2 turn...I've had no problems...and that was during engine build..Also you can find an old set of valve covers and cut the top out...about 1 1/2 - 2 inches the length of the valve cover.....Might help keep oil splash down if your going to leave the engine run...
 

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The engine does not need to be hot when setting the hydraulic lifter "preload". Hydraulic lifters are very forgiving and the difference in thermal expansion is insignificant. They best and easiest way to set the preload is exactly the way the manufacturers recommend. No mess and easy to do.
 

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The engine does not need to be hot when setting the hydraulic lifter "preload". Hydraulic lifters are very forgiving and the difference in thermal expansion is insignificant. They best and easiest way to set the preload is exactly the way the manufacturers recommend. No mess and easy to do.
Absolutely!!


I have a method I was wondering if it will work well. Could you use a dial indicator to find the max lift point of the camshaft, then turn the crank 1 revolution (180 degrees on the camshaft) then adjust the valve lash to spec? This would insure you are not on the lift portion of the camshaft so you have the proper pre-load. Maybe that's to much work though.

-Dan
Yes:yes:that would work just fine, but it's a LOT of unneeded effort. There are some hydraulic roller lifters out there now that require you to use a dial indicator to set the preload but the "intake closing - adjust exhaust, exhaust opening - adjust intake" method ensures you're on the base circle and is a lot less of a hassle. :yes:
 

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This is from Cranes website before they closed.

How To Set Valve Lash


When the engine is hot (at operating temperature), remove the valve covers and pick the cylinder you are going to adjust. When your engine is cold (after picking the cylinder you are going to adjust as described above), you will need to add .002” to your hot setting (Iron Block, Iron Heads) or subtract .006” from your hot setting (Iron Block, Aluminum Heads).. For Aluminum Block, Aluminum Heads, subtract .012” from your hot setting.



Hand turn the engine in its normal direction of rotation while watching the exhaust valve on the cylinder you’re working on. 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 cam lobe.)



Place a feeler gauge set to the correct valve lash between the tip of the valve stem and the rocker arm. Adjust until you arrive at the proper setting and lock the adjuster in place.



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. Use the feeler gauge and follow the procedure described above. Both valves on this cylinder are now adjusted. Move to the next cylinder and follow the same procedures


Hope this helps. Dave
 

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Valve lash setting has soooo many ways to do it that it's confusing. Some guys use a dial indicator with their cam info to do it. 1/4, 1/3, 1/2, 3/4 hot/cold ect. So here's another way. I'm no mechanic so take it with a grain of salt.
-cold motor, #1 @T.D.C. compression stroke. I pull my distributer cap to be sure. balancer at 0 degrees

-start with #1 intake or exhaust

-turn nut down slowly while twisting the pushrod in your fingers (I've used this method on the bike for decades) until it's very hard to turn.

-then crank nut 3/4 of a turn

-at the same time set #'s

1,2,5,7 intakes
1,3, 4, 8 exhaust

turn crank 360 degrees
set #'s

3,4,6,8 intake
2,5,6,7 exhaust
 

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Valve lash setting has soooo many ways to do it that it's confusing. Some guys use a dial indicator with their cam info to do it. 1/4, 1/3, 1/2, 3/4 hot/cold ect. So here's another way. I'm no mechanic so take it with a grain of salt.
-cold motor, #1 @T.D.C. compression stroke. I pull my distributer cap to be sure. balancer at 0 degrees

-start with #1 intake or exhaust

-turn nut down slowly while twisting the pushrod in your fingers (I've used this method on the bike for decades) until it's very hard to turn.

-then crank nut 3/4 of a turn

-at the same time set #'s

1,2,5,7 intakes
1,3, 4, 8 exhaust

turn crank 360 degrees
set #'s

3,4,6,8 intake
2,5,6,7 exhaust
Wow.......Now THAT'S old school.:yes::devil:
On milder cams it will work but on some of todays more aggressive profiles (especially with a lot of overlap) it's not the greatest way to do it.
 

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You can actually be preloading the lifter doing it that way. You should move the pushrod in an up and down motion until there is zero lash, then add your preload. By spinning the pushrod until it's hard to turn, you all ready put preload on it. Don't forget, a hydraulic lifter needs room to expand from zero lash. Some hydraulic lifters are forgiving in that they need 1/4 to 1 turn preload. Dave
 
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