Not a problem if you have an air source of 80+ psi.. Make or buy a spark plug to air adapter.. Buy or make an "over center" tool. Looks like an "L" shaped bar with a 1/2" hole in the heal. Most auto parts stock them for Chevies, will work on dodge with minor mods to pivot bolt and hole in tool.. Hook up air to cylinder. Swat spring retainer edge at a 30 degree angle with hammer to loosen the locks. Pry springand retainer with tool, to compress past the locks. Remove locks. A magnet helps here. Remove spring. The seal is pushed down over the valve stem and the valve guide. pry it up around the outer edge and slide it up and off the valve.. New seal set will have clear plastic sleeves that fit over the valve stem. These keep lock groove from cutting the seal lips. Slide sleeve over stem. Oil seal and slide down thw valve to the guide. Remove sleeve. Take a 3/8" drive x 1/2" deep socket. Turn it upside down, slide over valve stem/seal and push the seal down over the guide (approx 3/8"). Install spring/reatiner.. Compress until locks snap into place, release.. Go to next hole.. Back in the day,, I used to do this, changing springs, between rounds at the drags.. Using a 20 lb. CO/2 bottle for air pressure.. Got real fast at it.. Remember some cylinders will have a valve open at bottom of stroke, just do a different one, or rotate engine, till they are all done.. Air pressure at the top of cylinder will make piston go to bottom..NOW!.. keep appendages away from fan/belts etc.. =
Perfect advice! Follow it to the letter and all should go well. I might add one thing, be careful when installing the new seal a fool that I pay all his bill for one time bumped the valve stem and broke the air seal in the cylinder. It is amazing just how fast a valve can slide into the cylinder when the piston is down and you are surprised . I still live with this guy, entertain his wife and kids and look at his ugly mug in the mirror every morning. Good thing is he never did that again and that saved me from removing a head unnecessarily again!
I should mention.. Not to piss in any ones Wheaties.. But.. If you are having valve/oiling/coolant loss problems with the "Magnum" series of engines.. 239-360.. The head is cracked thru the valve seat. I get many of these in and see about a 95 percent fail rate. Always on a rear cylinder.. As bad or worse than GM 5.7 Vortec heads. Casting is too light and a coolant flow problem. Bad enuff that the aftermkt has new replacemant heads that are a couple of pounds heavier and don't crack. I have these heads on three of the four of my own Dodge trucks.
Two things, Google "replaceing valve stem seals" and watch the You Tube video. The video is for a Chevy but the same process applies to your engine. If you don't have access to air pressure you can get by with stuffing a few feet of 1/4" rope into the spark plug hole then rotate the engine until the piston pushes it against the valve holding it up and keeping the valve from falling into the cylinder.
The Jalopy Journal
