How to install valve stem seals while engine in car??

I need to change the valve stems seals in my 360 Magnum motor and need guidance. The engine is installed and want to know proper procedure to remove the old ones and install new ones.

Bring piston to TDC on that hole, replace spark plug with air fitting, apply air pressure to keep valves up, pop out the keepers on the spring retainer, remove retainer & spring, install seal.
With a shaft mount system it's probably easier to remove the rocker shafts; loosen bolts in stages to avoid the shafts getting bent. On my Street Hemi it was easy to just slide the rocker arms sideway on their positioning springs.
The keepers are small enough that they can easily fall into the heads, so use a lot of shop rags - preferably lint-free - to catch them.

I just went through this a week back with the AMC V8 in my Jeep.

You can "make" an Air-holding tool/fitting, by using a Spark-plug extender (available at autoparts stores) and 1/4-inch air-tool quick-disconnect fitting, plus some teflon-tape to seal.



You screw this fitting into the sparkplug hole for the cylinder you are working on and use compressed-air to hold/keep the valves from dropping down into the cylinders while you compress the valve-spring and remove the valve-keepers.

An older, alternative method, involves feeding small-diameter Rope, through the spark-plug hole, filling-up the cylinder. When the valve drops inward, the rope keeps it from falling all the way into the cylinder where it's un-retrievable (else you'd need to remove the cylinder head to get it out.)

You will also need an "On-Engine Valve Spring Compressor," to remove each spring. I bought a "Good" one for $40 at NAPA. I (also) bought a crummier one for $20 at Pep-Boys, though with weaker valve-springs, the cheaper one would likely work fine.



TIP: You should "hit/tap/smack" the valve-retainers (I used a wide, deep socket and rubber mallet,) to free-up the Keepers, otherwise they (sometimes) stick/bind in the retainer opening.

Quote:

---

I just went through this a week back with the AMC V8 in my Jeep.

You can "make" an Air-holding fitting, by using a Spark-plug extender (available at autoparts stores) and 1/4-inch air-tool quick-disconnect fitting, plus some teflon-tape to seal.

You use compressed-air to hold/keep the valves from dropping down into the cylinders while you compress the valve-spring and remove the valve-keepers.

---

is there a particular seal to use? One better than another? Available at the dealer?

Thanks