How the **** do I tighten down my Rockers!!!
04-25-2008, 06:47 PM
#11
4th Gear Member
Thread Starter
Join Date: Mar 2007
Location: Buffalo, NY
Posts: 1,541
RE: How the **** do I tighten down my Rockers!!!
ORIGINAL: 1fast86
the spec in the haynes manual is for a non adjustable valve train, you dont need shims. what you need to do is turn the engine to #1 tdc compression and adjust the rockers on the lifters that are ALL the way down in the bore, turn the rocker adjustment nut while spinning the pushrod with your fingers you will be able to tell when you have reache zero lash when you feel a slight drag on the pushrod. then tighten 1/2 turn and tighten the locknut. once you have done all those rockers turn the crankshaft 1 full turn and adjust the rest of the rockers. spin the motor over 1 more time and youll be on #1 tdc compression again. this always works for me, but its usually easier with the intake removed because it gives you a clear view of the lifters in their bores.
The easiest wayto shim the rockers is toput moreshims inthan you need (usually two one big one small) and work with one rocker until you find what you need (shim wise).Then use the process jwog666 said to run all the rockers.
the spec in the haynes manual is for a non adjustable valve train, you dont need shims. what you need to do is turn the engine to #1 tdc compression and adjust the rockers on the lifters that are ALL the way down in the bore, turn the rocker adjustment nut while spinning the pushrod with your fingers you will be able to tell when you have reache zero lash when you feel a slight drag on the pushrod. then tighten 1/2 turn and tighten the locknut. once you have done all those rockers turn the crankshaft 1 full turn and adjust the rest of the rockers. spin the motor over 1 more time and youll be on #1 tdc compression again. this always works for me, but its usually easier with the intake removed because it gives you a clear view of the lifters in their bores.
The easiest wayto shim the rockers is toput moreshims inthan you need (usually two one big one small) and work with one rocker until you find what you need (shim wise).Then use the process jwog666 said to run all the rockers.
what do u mean tighten a 1/2 turn then tighen the lock nut....i dont have studs with a nut i have a single bolt going through my rockers, i dont have 2 separet things to tighten....
anyways looks like i need to buy some shims, any suggestions on shims?
04-25-2008, 07:08 PM
#12
5th Gear Member
Join Date: Mar 2008
Location: wisconsin
Posts: 2,260
RE: How the **** do I tighten down my Rockers!!!
ORIGINAL: jwog666
my bad, missed the pedestal part, i thought you were talking about stud mounted. way less pissin around
my bad, missed the pedestal part, i thought you were talking about stud mounted. way less pissin around
04-25-2008, 07:10 PM
#13
6th Gear Member
Join Date: Apr 2007
Location: California
Posts: 10,468
RE: How the **** do I tighten down my Rockers!!!
This is what you need to do....
First you have to know what the torque spec is and how many turns past 0 lash you need to have once you reach it. Make sure the lifter of the valve you're setting is on the cam's base circle(ie, the valve is totally closed and the lifter is all the way down, such as on the power stroke). You finger tighten the capscrew on the rocker(using a nut driver type of tool helps here) until you have 0 lash, ie when both ends of the pushrod are seated in the rocker cup and the lifter plunger but the lifter plunger is NOT depressed. Once you are at 0 lash, you torque the capscrew for the rocker to it's specified torque REGARDLESS(you need to use the torque setting for the rocker manufacturer). You MUST have it torqued all the way do or you're valvetrain won't survive. The rocker manufacturer should have a specified number of turns(usually 1/4 to 1 full turn) that you should go past 0 lash until you reach the torque setting. Basically you torque the rocker down and it should be the x to y number of turns to reach z torque specification. That will give you the proper .020-.060 lifter preload on the hydraulic lifter. If you can't go to the minimum number of turns then you need longer pushrods, if you go past the maximum number of turns then you need to shim, but in either case the rocker geometry needs to be correct.
If your spec is 18lb-ft then you need to hit that torque setting within the specified range of turns past 0 lash, if not then a pushrod/shim change is needed.
First you have to know what the torque spec is and how many turns past 0 lash you need to have once you reach it. Make sure the lifter of the valve you're setting is on the cam's base circle(ie, the valve is totally closed and the lifter is all the way down, such as on the power stroke). You finger tighten the capscrew on the rocker(using a nut driver type of tool helps here) until you have 0 lash, ie when both ends of the pushrod are seated in the rocker cup and the lifter plunger but the lifter plunger is NOT depressed. Once you are at 0 lash, you torque the capscrew for the rocker to it's specified torque REGARDLESS(you need to use the torque setting for the rocker manufacturer). You MUST have it torqued all the way do or you're valvetrain won't survive. The rocker manufacturer should have a specified number of turns(usually 1/4 to 1 full turn) that you should go past 0 lash until you reach the torque setting. Basically you torque the rocker down and it should be the x to y number of turns to reach z torque specification. That will give you the proper .020-.060 lifter preload on the hydraulic lifter. If you can't go to the minimum number of turns then you need longer pushrods, if you go past the maximum number of turns then you need to shim, but in either case the rocker geometry needs to be correct.
If your spec is 18lb-ft then you need to hit that torque setting within the specified range of turns past 0 lash, if not then a pushrod/shim change is needed.
04-27-2008, 01:28 AM
#15
3rd Gear Member
Join Date: Feb 2008
Location: Florida
Posts: 836
RE: How the **** do I tighten down my Rockers!!!
When you measured for correct pushrod length, did you use a solid lifter or hyd. that was converted to solid? This is necessary, if not your pushrods may be too long. How did you do your measurements? (Without shims, rocker torqued down, and checked for the the correct pattern at the valve tip)
If this was done with a solid lifter, torque down the rockers andthe pushrods should still be able to be rotated with you fingers (but not loose). If they will not rotate, shims will have to be installed. Begin with the thinnest shim and repeat the above procedure until the pushrods can be rotated without any play. Make sure you do this for each cylinder when each is at TDC or thelifter is on the base circle of the cam (not on a lobe).
If this was done with a solid lifter, torque down the rockers andthe pushrods should still be able to be rotated with you fingers (but not loose). If they will not rotate, shims will have to be installed. Begin with the thinnest shim and repeat the above procedure until the pushrods can be rotated without any play. Make sure you do this for each cylinder when each is at TDC or thelifter is on the base circle of the cam (not on a lobe).
Thread
Thread Starter
Forum
Replies
Last Post
69MustangCoupe393cid
Archive - Parts For Sale
2
10-03-2015 10:33 AM
