I can't say it's exactly the same, but it sounds a lot like what happened to Dave in the '50 GMC once.   The Jimmy has a column shift, and I presume the Plymouth does as well.

I don't know what Dave did, but the linkage was jammed up like typewriter keys and wouldn't even budge when I attempted to manipulate the column-to-transmission connecting rods by hand under the hood (something that has always quickly cleared similar but less severe trouble in the past).

The truck had to be towed, but it indeed turned out to be nothing more than the linkage that needed to be freed up.  The mechanic gave Dave a lesson in how the transmission wanted to be shifted.  I used to cringe whenever he was behind the wheel of the Jimmy because of the way he murdered the entire drive train.  I've been driving that truck since 1971 and when I'm behind the wheel it's like an extension of myself.

I'm not sure what to make of the Plymouth starting but also not budging with the clutch disengaged, but it makes me think the clutch is not the problem.  I think you're on the right track and should for sure check the linkage to see if it has gotten sloppy or a component has failed.  I hope it's an easy fix like you're thinking it might be.  Keep us posted.

Ralph

Shift Linkage all the way.  Now, you can take a look under the hood and manually if you know how, put it in a gear such as first and drive it home very slowly and do not attempt to change gears via the shift.  Then have the linkage fixed.  Let us know how it works for you..................

It could also be seized up rear brakes, or seized up parking brake.

I actually have two 1950 Plymouth four door sedans. One runs and ready to go at any time. The other one was bought with a frozen motor and is basically a donor car, although the body is very straight with little rust.

I have on occasion driven off with the parking brake lightly engaged, only to find that as it heats up it will very suddenly bring the car to a screeching halt. It works by compressing an asbestos cloth lined steel band around a drum on the driveshaft. at the rear of the transmission.

I actually tore down and rebuilt a spare '50 Plymouth transmission in a manual transmission class about five years ago. These are very simple transmissions, and relatively easy to take apart and put back together. I suppose something internal could have busted preventing proper shifting, in addition to problems with the external linkage.

I assuming you keep it topped up with gear oil...

Never had any problems with it that I could trace to the external linkage, though. Shifting into reverse can be a little balky, probably the reverse gear has some chewed up teeth, which is common in an older manual. There is only one synchro ring in these trannies, aiding the downshift from third to second. No synchro is needed to shift from 1st to second, as I recall. And yes, the car can start on a level surface in second, no problem. 1st is very low but helpful for very steep hills. In which case it's usually advisable to shift into 1st before entering the grade. LOL.

As far as top speed goes, these engines redline at 3600 rpm, which translates to about 65 mph. However I do try to keep it under 60 on the freeway. The cars themselves handle relatively well considering their era, but the skinny rims and stock tires do limit cornering. The steering box is relatively low effort with lots of turns and a wide diameter steering wheel.

One can probably find a replacement used transmission at a vintage car wrecker, or on eBay. They are easy to pull and replace, if you have a transmission jack.

The runner 50 has a vacuum wiper system and a vacuum booster pump running off the same cam that powers the fuel pump. It is infinitely adjustable in speed, although usually a slow speed is preferred as it can go nuts when compression braking downhill. I find vacuum wipers to be highly entertaining.

Stan, you already know this, but one thing is for certain.  The way to keep cars like this in proper working order is to drive them.  The reason my GMC still starts right up and drives reasonably well is because it has never sat idle for more than maybe a month since it was new.

Well, unless you've noticed a major gear oil stain under the car, I'm guessing it's probably OK, but it doesn't hurt to check.

Come to think of it, I haven't checked mine for probably about five years now. At least.

And no, while I used to drive it daily, back in the 90's, I decided around 2003 to give it a rest and drive it maybe 3-4 times a year, to car shows or just to limber her up. Doesn't seem to hurt, but I do keep it garaged. Most recent repair has been to starter solenoid, which on this vehicle is conveniently located bolted to the side of the engine compartment just above the driver side wheel well. Near the battery. The old one, probably the one that came with the car in 1950, was sticking in the ON position, so it wouldn't stop spinning the starter even after the ignition key was turned to on instead of start. Revving the motor usually would flick the starter off, but I don't like revving a cold motor. A whack with a hammer worked to, but that was a temporary measure. Found a serviceable new one online for about $25 and it works fine. Just doesn't look as ancient as the original (bakelite bottom case instead of all metal case).

These old cars are sort of hard to kill. The motors are simple, low compression, low HP (98) very torquey, etc. They will run with scored cylinders (don't ask), burnt valves, etc. Probably would run on diesel as well. It's a basic motor design that Chrysler debuted in 1924. Downsized for the Plymouth around 1930 and gradually updated. The motor stayed in production cars until the late 1950's when the slant-six came along, and was still produced and used in various industrial settings like fork lifts for decades more.

The one aspect that is annoying is getting a smooth clutch release. The "Floating Power" feature lets the motor rock too much and then the clutch grabs and shudders. If the FP motor mounts are tightened up the shuddering is reduced or goes away, but then there is too much motor vibration transmitted to the frame. I've tried all sorts of mount settings, nothing really resolves the problem. Talked to other owners with the same experience. I know it's not me because the '67 Chevy Van with MT has silkly smooth (well, sort of) clutch engagement. I even tried replacing the clutch and resurfaced flywheel (twice), no luck. It's got a 10 inch clutch in it now, so it never slips.

Sometimes starting in second is the answer. It's enough to make one want a fluid clutch, until one remembers how much power those things sapped.

The transmission on the GMC had a drip from the filler plug for quite a while, but not to the point of leaving obvious evidence on the driveway.  I'd just notice it when I was under the truck for other reasons.

For years, after sitting at a red light in neutral with the clutch disengaged, when the light turned green and I'd depress the clutch I'd get grinding that would wind down over a period of five or ten seconds as I attempted to engage first gear.  I got used to it and knew to anticipate it.

Then a year or two ago the transmission was getting noisy and it sounded like an old milk truck.  I decided to check the gear oil level and add some if necessary.  It took well over a pint!

The milk truck noise was gone and the grinding issue cleared up too.  Now the light turns green and off we (relatively) quietly go.  I made sure the filler plug was good and tight when I replaced it.

It's worth topping off the gear oil before investigating the linkage.

As I recall on long trips I have averaged about 20 mpg in the four door '50 Plymouth. Like any standard (non-hybrid) car, mileage plummets in stop and go traffic, or around town.

I do recall getting better mileage before California started adulterating the gas with MTBE and, later, ethanol.

I've had the GMC up to 65, but I don't feel safe going that fast with it on crowded area freeways -- or even empty ones, plus it gets pretty loud in the cab.  It seems to have a sweet spot at around 57, so that's where I tend to top out, and I always keep to the far right lane.

So Stan, what happened to that (flowering cherry?) tree?  Did it get struck by lightning or something?

My second engine rebuilder was rather adamant that I not drive the car above 55. He said the motor was never designed for sustained top speeds, and the bearings and rings would wear out quickly if pushed to the limit. I had top components installed the second time around... forged pistons, tri-metal main bearings. And relatively tight tolerances. It doesn't burn any oil after 20 years, so there is that.

The larger Dodge/Desoto/Chrysler 230 and larger flathead sixes can be longer lived, mainly because there's more room in the block to space the cylinders with more meat around them. The 218 block was shortened and hence the cylinders are rather closely packed. This limits the amount of overbore that can be done, and also affects cooling.

Plymouth was the entry level car for Chrysler Corp. It is a good car but certain economies were taken in production. Oddly, it was their smallest car but even the smallest 50 Plymouth today would count as a full-size car.

The rear main seal will always seep a bit. The secret to a less leaky one is to avoid the rubber seals and only use a rope type seal. It won't seal as tightly to begin with but it also won't deteriorate quickly from heat and age like the rubber ones will. And besides, the engine breather tube exits under the chassis, keeping the road oiled anyway.

Gee, it's not like the last Plymouth was produced in 1950.   Plymouth doesn't make smart phones.  If they did, that person would have known how to spell it.

I'm glad this is looking like it's not transmission related.  The linkage and E-brake are relatively simple and inexpensive repairs.

Stan, it's the tree in the photo of your car above, in the foreground parking strip.  It looks like half the trunk of it (the tree, not the Plymouth) is missing.

Ping, Stan, what's the verdict?

"The mechanic hasn't gotten to it yet."

Happy ending!

Good Story Stan.  Didn't I say the linkage from the get go?  They failed on all sorts of makes and models due to the nature of usage and being constantly moving while shifting.  It can leave you with the impression (unexplainable) that there is a major issue going on.  

Glad you have your car back home and all is well.

--Steven

That only happened to me once with the GMC while taking the Waldo Grade in the downhill direction, most of the time with my foot off the gas.  The shift lever was seriously vibrating, and then it just popped into neutral on its own.

There is probably a procedure for dialing in the linkage setting so they don't pop out of gear or clash. It would be in your service manual, which you have, of course!

And here is a link to a wholesale closeout of various 1950 Plymouth parts:

www.rockauto.com/RSS/vehiclefeeds...

Like I said, these transmissions are very simple affairs and not rocket science to rebuild. The bearings are likely standard and readily available off the shelf or online. That is, if the noise is actually a transmission bearing and not dragging brakes.

However the idea that old cars last forever is a myth. They were designed when labor was cheaper than advanced materials so they typically require much more maintenance than newer cars. Softer alloys, less durable rubber, more primitive lubricants, etc. So we tend not to drive them as often or as far or as fast as new cars, and save them for special days.

After that visual, if I were within closer range I'd be happy to assist.  I could use a change of scenery after dealing with the brakes on the Jimmy without the desired outcome, and I have successful experience with a Rambler driveshaft under my belt.  

Those among us who know me know just how I mean that . . .

I did those last year on mine...all four wheels!

The '50 Plymouth, unless changed out, has ball and trunion U-joints fore and aft, also called Detroit U-joints. These can and do wear out. Most frequently the rubber sleeve covering the U-joint ages and cracks or tears. Then the grease inside can be lost or contaminated.

Inside the U-joints is a smaller shaft, with a ball on the end. The ball is bisected by a trunion pin. On the trunnion pin ends two more balls are fitted, which ride on needle bearings so they can rotate on the pin. The whole assemble then rides inside a heavy cast and machined housing, which has grooves to accept the needle bearing equipped trunion balls. So the U-joint can flex in the with regard to the driveline radial direction as well as move in and out in the driveline axial direction.

Proper rebuilding of the Detroit U-joint, including replacement of the rubber sleeve, involves pressing out the trunnion pin on a big hydraulic press. An automotive machine shop should have one, but you might have to look around for a machinist or mechanic willing to press out the pin and/or rebuild the U-joint.

When you get under the car you can inspect the rubber sleeves for integrity, and see if the driveshaft can be moved by hand forward and backward. If not, it might be seized up.

Usually the noise, I'm told, is a loud clunk when going over bumps and/or under load.

What I've seen is that the heavy machined casting that the trunnion runs in develops wear spots where the trunnion balls usually ride. Or there's a rubber sleeve/lubrication failure.

It's not too difficult to pull the driveshaft with the U-joints attached, but of course it's dirty uncomfortable work on your back under a car jacked up and on stands. (Don't rely only on jacks!). After that fixing the damn Detroit U-joints is no picnic, and pressing out the trunnion pin can be dangerous involving very high pressures. Pressing in a new pin requires a careful technique, because you want it to be centered on receiving ball. One mechanic who pressed mine in machined a spacer so that the pressing would stop at the right point.

Have fun.

I'm a car nut so I like to see their innards.  My VW has 314,000 miles on it currently.  I kind of sort of have a feeling the dual mass flywheel is going out.  Still running original clutch!  All of that would get changed out if the above scenario does play out.  I'll be due for a timing belt and water pump in about 5500 miles.  I miss the simplicity of my old diesel Rabbit from 1980, but I can't complain about this 2001 bug that I bought new for my 30th birthday.

Interesting!

I also have a 1950 Plymouth, a "Special Deluxe". Her name is Bubbles. Part of the agreement so I could purchase her was to keep the name, LOL. I've had Bubbles for over 28 years. Used to drive her a lot. That clutch sure does look familiar.

I've replaced a lot of parts on Bubbles. Had the motor rebuilt - they didn't do a very good job, had to rebuild the motor again after about 2 years and 27,000 miles. The rings they put in were scoring the cyclinder walls. This time I pulled the motor myself and took it to a better machine shop.

She has a manual transmission (I don't think Plymouths had automatics in 1950), which works quite well. Found the little service book (had to go out to garage to fetch it).

Last time I drove Bubbles was in 2017. So she probably needs an oil change. Maybe a draining of the gas tank, too. IDK. Have to check coolant as well. And the battery may be dead. Such fun!

Yeah, I'm making plans to drive her again before this summer is out.

AFAIK, the 1950 Plymouth has NO synchro for 1st gear.

Thanks Rich I was quite sure there was no Sysco in first gear in a 1950 Plymout.

When Jeff and I started this business in 1979 we went out and bought two short wheelbase dodge tradesman 1974 vans with 225 slant sixes and three speed on the column they didn’t even have synchromesh in first gear, it made it kind of challenging in traffic because you had to come to almost to complete stop or double clutch to get it back into first gear and my van didn’t have power steering or brakes somehow or another Jeff’s van actually had power brakes.

I also think it’s unusual that you’d have trouble with a bad clutch slipping in third gear usually a bad clutch slipping it’s hard to even get the car Up to speed in first or second gear with a bad clutch.

I almost never comment on anything if I’m not absolutely sure about.

John L