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-   -   Novice question, adjusting rocker arms - lifter noise (https://67-72chevytrucks.com/vboard/showthread.php?t=157267)

Yukon Jack 05-24-2005 08:39 PM

Novice question, adjusting rocker arms - lifter noise
 
Just got my exhaust installed today and have some noisy lifters. The engine is a 1989 454 with a 266 Energizer cam, hydraulic lifters, and Comp cams rocker arms. How do I go about adjusting the rocker arms? My buddy assisted with the cam install and I don't know how to do this adjustment.

chevy72blu 05-24-2005 10:51 PM

take off the valve covers and put a turn or two on the rockers that feel loose. Im sure using a torque wrench is a better way to do it, but doing it by feel has always worked for me. Make sure not to tighten em down too much.

You sure it isnt an exhaust leak? One time I thought I had a lifter clicking, and it was just a header gasket leaking a strange way.

jhow66 05-24-2005 11:08 PM

Here is an easy way to do it by firing order.
1--measure the circumference of balancer.
2--divide by 4
3--using number obtained in "2" mark new lines (3) around balancer starting at timing mark. ( example-if # is 4" mark a line 4" from timing mark-another line 4" from the new mark and another 4" from this mark) You now should have 4 lines that are equal distance apart.
4--Start with engine at TDC on #1 cylinder--adjust both valves. (rotate push rod between fingers while tightning rocker nut. When you feel resistance stop and turn the nut 1/2 turn more-or what your specs call for.
5--rotate engine 90* (engine fires every 90*) to your 1st mark you made. This will put #8 cylinder on TDC firing stroke-adjust both valves.
6--rotate 90* more for cylinder #4
7--just keep rotating 90* until all cylinders are adjusted (1-8-4-3-6-5-7-2)

bubba2 05-25-2005 10:44 AM

When adjusting hydraulic lifters, your goal is to place the piston within the lifter at the center of its travel. To do this requires that (1), the lifter to be adjusted is setting on the base of the cam--not on any part of the lobe. This is why you turn the engine over untill the cylinder you want to adjust is at TDC on its compression stroke. (2) to insure the internal piston of the lifter is at the top of its travel, back off the adjustment until you can easily move the rocker. Wait a few seconds and test for looseness again. When your sure the piston has moved to the top of its travel, then very slowly tighten the adjustment nut as you turn the push rod with your fingers. The "trick" is to feel the slightest resistence in turning the pushrod. This indicates "zero" adjustment. Then, and only then, you turn the adusting nut down another 1/2 to 3/4 turns. The secret is in determining when you are at zero lash. This requires practice.
Roger

Burt4x4 05-25-2005 02:01 PM

Quote:

Originally Posted by Yukon Jack
Just got my exhaust installed today and have some noisy lifters. The engine is a 1989 454 with a 266 Energizer cam, hydraulic lifters, and Comp cams rocker arms. How do I go about adjusting the rocker arms? My buddy assisted with the cam install and I don't know how to do this adjustment.

hahah me too YJ, well my pass side is noisier than the drivers. I too need to learn how htios works. I have read bout the TDC and turning the push rod trick. I guess the hardest part is gettting that pistion at TDC.
Should both vavles exhaust & intake be loose or free when the piston is TDC? or is it just one of them will be loose?

Yukon Jack 05-25-2005 02:31 PM

Here are a couple links I have come across that are helpful

http://www.centuryperformance.com/valveadjustment.asp

http://www.boostandfuel.com/support/setting_valves.htm

http://www.2quicknovas.com/happyvalves.html

Burt4x4 05-25-2005 02:59 PM

Cool thanks for the links :metal:

xethln 05-25-2005 07:09 PM

I dont know about a 454, but I took my valve covers off and started the truck and let it idle, then slowly backed each valve off until it started to click then I tightened it one full turn and it works fine.

us111 05-25-2005 09:41 PM

valve's
 
2quicknovas are the easiest way i have ever seen it explained in my opinion... simple,easy to understand...good luck... ;)

Yukon Jack 05-25-2005 11:48 PM

After getting exhaust on the truck the motor had noise that sounded like a couple rockers needed to be adjusted. I pulled the passenger side valve cover and my eyes were met with the sight of three rocker arms sideways. The second pushrod from the rear of the engine is bent up top a bit and must be bent very badly below as I can't pull it out. The other two pushrods where the rockers were off came out straight. I didn't even have the heart to pull the driver side valve cover.


What a terrible let down after being so close to the end. I guess the passenger side head must come off to get that pushrod out and see what damage is done.

I assume I should be expecting bad engine damage . . . ??

Jason915 05-26-2005 09:38 AM

well I wouldn't expect bad engine damage just yet can you tell if any valves are bent? Sounds like you just trashed some valve train parts. Next time around make sure your valve lash is correct it's real easy to set it while your intake and valve covers are off. Good luck

Yukon Jack 05-26-2005 10:09 AM

I'm getting lots of good advice in a post I have over in the 67-72 message section. Hopefully damage will be minimal. We sure thought we had the valve lash proper, but something obviously wasn't right. The valve lash was set when the intake and valve covers were off. I'm keeping my fingers crossed.

Burt4x4 05-26-2005 11:17 AM

I'm doing a Postive Karma dance for you, so everything is gonna be alright.... :metal:


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