Valve Spring Change w/ Heads on Engine

[911 tweaks]

Is there a general consencus on how to change the valve springs while the heads are on the engine?
****Obvious concerns... NOT dropping valve into cyl & NOT scoring the valve shaft while holding onto it to compress the springs to remove keepers and thus be able to remove all pcs****

Basically, I am considering using the "Smart Racing #134100 = Springs, Retainers & Bases" to add engine protection when I know for sure that the engine will get buzzed from miss shifts.

Anyone tried this kit before? Did you use something different to minimize valve float at hi rpm or engine rpm buzz situations?
Thanks, Bob

[cgarr]

Bob, I have never done it on a 911 engine but have on my O-200, should work the same way, some will pressurize the cylinder to hold the valve in place, what I did was feed some nylon rope through the sparkplug hole then bring the piston up slowly, this compresses the rope against the valve and holds it in place. When your done, back it off and pull out the rope.

[911 tweaks]

sounds great Craig! To remove the springs do you use the specific factory intake & exhaust tools that attach to a bolt on the head?
Bob

[HawgRyder]

There are tools which look something like a "pickle fork" ( the tool for breaking ball joints apart).
They pry the retainer down using the rocker arm shaft as a fulcrum.
To remove the rocker arm: slide shaft out....remove arm...slide shaft back in without rocker...protect the shaft with a pad of some kind....do the rope trick....pry the retainer down (might have to give it a shock with a hammer to break the tension on the retainer clips)....change springs...reassemble.
Good luck
Bob

[911 tweaks]

thx Bob for the input.
It sounds like the valve spring compression tools you are suggesting are not the traditional intake & exhaust oe tools?
Do you have a pic of what you are suggesting?
Thx Bob

[TimT]

this tool is pretty handy for trackside repairs..

[ChrisBennet]

IMO, you should just pull the motor and do it. Doing it in the car is no way to learn.
-Chris