How to ReAdjust Pedestal Mount Roller Rockers

[UpRise_5.0]

Hey,

I have some ticking noise comming from my engine.

Refer to this thread for more info and a video clip with sound...

http://forums.stangnet.com/showthread.php?t=722173

Im thinking it might be one or more of my Cobra 1.7 Roller Rockers, how do I re-adjust them/set them up better so I don't get a ticking sound?

Do I need to take off the upper intake to get to the valve covers?

Thanks

 

[ninety15.0]

You will need to take the upper intake off to get to the driver's side VC. It much easier with the upper off anyways...and it only takes a couple minutes to get the upper off.

You need to get a socket and breaker bar on the crank pulley to manually turn the motor over. This generally means getting the fan and shroud out of there to make your life easier. You may be able to turn the motor over from below...but it just easier to take the shroud/fan off and turn the motor over from up top while you are working on the valvetrain.

I like to do this process in the order the engine fires: 1-3-7-2-6-5-4-8

Here's the proper procedure for adjusting the intake rockers: When adjusting the intake valves you will be concentrating on the position of the exhaust valve. Turn the engine over IN THE DIRECTION OF OPERATION (clockwise looking at the front of the motor) so that the exhaust valve on # 1 just begins to move. This means you are on the base circle of the cam on the intake side. Not loosen the poly lock on the intake rocker. Use one hand to spin the pushrod between your fingers while slowly tightening the polylock. Once you start to feel resistance on the PR you are @ zero lash. Go 1/2 turn past Zero lash on the polylock and tighten the set screw. Repeat this process through the rest of the intake valves.

Follow these instructions for adjusting exhaust valves: Concentrate now on the position of the intake valve. Turn the engine over so that # 1 intake valve is at peak lift. Rotate intake valve past peak lift and down about 1/2 way. Now the exhaust valve is closed and you can follow the same zero lash + 1/2 turn adjusting procedure.

Make sure all set screws are tight and button it up. Good luck man.

 

[jeffnoel]

The only way to adjust the Pedestal mount rockers is with a shim kit, the shim kit is around $10 and comes with 16 / 0.030 and 16 / 0.060 shims. And pedestal rockers don't have Poly locks.

First make sure whichever valve your going to "Torque" (not adjust) is closed then loosen that rocker bolt, screw it back in by hand until it stops then torque to 16-18 ft lbs. Use your torque wrench like the hands of a clock if you start with the wrench at 12 o'clock you should reach torque between 1/4 and 1 full turn or 3 o'clock and 12 o'clock. If it doesn't reach torque intil past 1 full turn you need to add a shim under the pedestal, if it reaches torque before 1/4 turn you need to either go with a thinner shim if it has the thicker one under the pedesatl or remove the shim shim completely. I that doesn't work you need a different length (shorter) push rod.

Here's the pdf from Crane Cams on installing Pedestal mount RRs http://www.cranecams.com/pdf/453e.pdf

I prefer to shim my rockers to were I reach torque between 1/4 and 1/2 turn otherwise your loosing cam lift.

If you'd like to check your valvetrain geometry, remove a rocker and wipe theoil from the valve top and roller rocker tip. Take a sharpie and cover the valve tip until it's black then reinstall and torque that rocker. Rotate the engine a couple complete revolutions by hand then remove that rocker again and you will see were the roller tip removed some of the marker from the valve if your geometry is correct the line should be narrow and cut right through the center of the valve.

 

[jtfairlane]

Yikes.

Don't listen to ninety15.0, he gave you instructions for adjusting STUD MOUNT rockers. Your pedestal mount rockers do not have poly locks and they are not stud mount.

Also, jeffnoel is only half right when he says the only way to adjust pedestal mount rockers is by shimming them. You can shim them if you need to, to gain more turns on the bolt. But, you can also reduce pushrod length if you need to. Jeffnoel provided good instructions and a good Crane pdf file to work from. Unlike adjustable stud mount rockers, you are in fact torquing your pedestal mounts to a specific value with the piston at TDC on the compression stroke for each cylinder (with the valves closed).

 

[ninety15.0]

You're right i did give him the explanation for stud mount. Yikes is right. Excuse my previous post. Procedure still applies for finding base circle...but do follow shimming procedure for ped mount rockers.

 

[88mouse]

Shimming ped mouth rocker will only make it worse. Either get shorter push rods or you can grind off the ped that the rocker rides on (Not the head the other little piece.).