Valve adjustment


302Z28
04-17-2011, 10:42 PM
I decided to replace the head gasket on my '97 2.2 Cav. As part of the process, I had the head re-surfaced. Prior to removal of the head, I ran a compression test. The readings were: 175, 170, 168, 170. After re-installing the head, the rocker arm nuts cannot be torqued as outlined in the Chiltons manual. Torquing results in the valves being held open and zero compression. Adjusting the valves to zero lash, plus 1/4 turn results in compression readings of 210, 180, 180, 220. The valves are very sensitive to any adjustment. It seems as there is a very fine line between zero lash, the compression readings above and zero compression. I'm stumped.
Any ideas?

Schaff68
04-21-2011, 05:50 PM
might sound odd, but some car companies want you to replace the head bolts or studs after changing a head gasket or head, and some rocker arm adjusting nuts are a one time onley use, meaning you have to buy new self locking nuts each time you work on the head. some companies require that you buy .010 or .020 shorter pushrods or followers after you have a head resurfaced and some of the nuts or studs are meant to be at the very end of their adjustment once they are torqued down, so if you have installed a none GM 2.2 specific head gasket, GM should list the thickness once compressed, and had your head resurfaced, you may need to buy the proper lenght valve train components so everything adjust right. i know its a pain, but when your dealing with valve train parts, some cars dont leave you much adjustment. thats why performance engines require certain ratio rockers, custom lenght pushrods and a fully adjustable valve train. and yes i know its just a common 2.2 but if things are out by enough thousands, you may need to buy other followers or ect. as in .010 or .020 shorter so things line back up properly

FishFind
04-21-2011, 07:23 PM
what about the springs on the rocker arm? are they still good? You are supposed to use a mic and make sure they are in a specific range.

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