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Valve Adjustment Help

A friend of mine called last night to let me know he just bought a mint condition 1955 Plymouth with a flathead six and Powerflite, and asked if he could bring it over next weekend for a tune-up. I would normally adjust the valves as part of that process. As I recall, when adjusting valves on those old flatheads, I would hold the feeler guage in my left hand, and three! open end wrenches in my right hand, one for the locknut, one for the adjuster, and I can’t remember what the third was for. Anybody out there remember? Thanks in advance for any help.

Google ‘Plymouth flathead six valve adjustment’ and look at the videos, that should remind you.

Thank you, I wouldn’t have imagined they’d have something that old online.

People video the STRANGEST things and post them online! Including old car maintenance. YouTube can be a great resource. I use it often to see how things come apart. It is important to know where there are retaining tabs on plastic parts, or to know where the hidden screw is when disassembling things for repairs.

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This might be close to what you’re looking for

Thanks. I actually remembered last night what the third wrench is for. The adjuster is two pieces, you have to hold one piece while turning the other. The third wrench, as I had thought, is to tighten the locknut. I found a number of relevant posts online this morning, and the one thing they had in common, which I already knew, was “These engines are a b***h to adjust the valves on”. I shouldn’t have answered the phone:) Now I’ve got to go see if the Sun engine analyzer that I haven’t used in many years, still works.

Well, I just finished this thing and my fingers feel like they spent a day in a meat grinder. The Sun machine still worked perfectly. My friend is a cardologist and he was completely fascinated by the ignition scope. He said it’s amazingly similar to an EKG. I had been somewhat concerned about the Powerflite transmission after 63 years, but I hooked up my gauges to the various ports, and the oil pressures were right at the specs. We went for a ride, and to quote Tom McCahill in his test of the 1954 Chrysler New Yorker, “the new Powerflite transmission is as smooth as a bucket of warm whipped cream”. Chrysler truly did have the best engineering back then. It’s a shame to see how far they’ve fallen.

lol … sounds like whenever I do anything major with brakes. Or attempt to install a new air filter in the Corolla :wink:

My family had a 50’s Newport with the button-control transmission (Powerglide I presume) and it indeed seemed to perform well. I got to press the buttons sometimes, which was a treat for a kid. That transmission didn’t take to dragging a small holiday house-trailer up a steep hill in summer on the way to a family fishing trip though. We had to stop almost every mile and let the transmission fluid cool down 'til we reached the top of the hill. Not a problem for me, just chased after the lizards off the side of the road.