Introduction To My 1948 Desoto & A Young Vintage Mopar Owner

[CarlN-NDC]

Hello All,

 

  I own a 1948 DeSoto S-11 Custom Club Coupe.  I purchased it in September 2020, it is my first project car & first pre model year 2000 car I've ever owned!  Now is a good time to say I'm probably one of the youngest members on here (22-years old), but have a great respect for these old cars and want to keep my 48' DeSoto as stock as sensibly possible.

 

  While I've had the car for about 2-1/2 years, I haven't physically done a ton of work to it.  I am a read the manual cover-to-cover type of guy.  So out of principal, I've taken the last 2 years to study books, forum threads, and videos on these old Mopars before barreling in.  Opposed to taking things apart, have no idea what I am looking at, and then end up with a pile of parts and me scratching my head!  As such, in these past 2 years, I've learnt ton about flathead engines, or L-head if we're being technical, Lockheed drum brakes, the Tip-Toe shift transmission (My DeSoto has the M5), the difference between the semi-auto shifting transmission and Fluid Drive coupling, and how to properly repair and maintain a 6-Volt positive ground electrical system.

 

  Now I feel decently prepared to finally get my hands dirty and work towards getting my 1948 DeSoto back on the road!  A little background on my car.  It spent most of it's life, both active and while it sat for several decades, in Worcester, MA.  It is now in NEPA (Northeastern Pennsylvania).  It has 118,700 miles on the odometer.  It was last on the road/inspected in April 1960.  The black paint is original as far as I can tell.  It has the original 237ci flathead engine in it, including the "S11" stamp on the side of the block!  It has the M5 Tip-Toe shift transmission with Fluid Drive coupling.  The wiring harness....exists, but I would not dare to put a 6-Volt battery in to even "see what works".  All the wires in the engine bay, under the dash, and in the trunk are crusty, corroded, and the cloth insulation crumbles at the slightest movement.  On a positive note, none of the wheels are locked up, so hopefully when I go to pull the drums off it won't be a nightmare.

 

  Unfortunately, said original S11 engine is locked up.  Before everyone types-up all of their remedies to freeing up a stuck engine, I already know what the cylinder walls look like....it would do serious damage if I did manage to free it up.  Two members from the Maryland Chapter of the National DeSoto Club graciously made a house call this past October 2022 and helped pull the cylinder head....the diagnosis is not good.  A broken head gasket right between cylinders 3 and 4.  Those two cylinders must have sat full of coolant for decades and rusted the cylinder walls and pistons in place.  As long as the block is not cracked, I do intend on reusing the original block, but it will definitely have to be bored-over .030, .040, .060..??

 

What are my plans:

  A full mechanical and electrical restoration, but keep the body work to a minimum.  I don't want to create a show car with perfect paint, I would never drive it if I did.  There are definitely some rust issues that need to be addressed.  The chrome rocker panels are hiding the majority of the rust.  It needs both inner and outer rocker panels on both sides.  Also, the trunk pan is quite thin on the driver's side, so much so, the seem running along the inner wheel well has separated!

 

  Currently, I am planning and gearing up for an engine pull in the next month or two.  I already have an engine puller, load leveler, and engine stand.  I plan to do the complete disassembly myself: intake and exhaust manifolds, valves, tappets, camshaft, pistons, crankshaft, etc.  Then I will take it to a machine shop and have it boiled out (get that rust, scale, and sludge out!).  Have it checked for cracks, and if it passes, then have them tell me how much it needs to be bored-out to get to all clean/fresh metal.  Aside from the boring-over, I'll have the machine shop deck the top of the block, install new valve guides, and maybe have them install new valves and lap them.  I am definitely getting all new valves, just not sure yet if I'm going to lap them or have the machine shop do it.  All other reassembly I plan to do myself.

 

  As I've said, I've spent the past 2 years researching.  I've actually read through many threads on here as a guest for over a year!  I figured it might be fun/helpful to create an account now that the work is starting so I can post my progress updates!

 

Thanks for reading!

 

Carl

 

 

I know you all love photos, so here are a few, and so you can see the unfortunate state of my engine!

 

Obligatory photo when I rolled it out of the garage this past Fall 2022:

 

A photo I found of my DeSoto at an auction before I purchased it:

 

Driver's side rear quarter panel.  Worst of the visual body panel rust.  But the rocker panels are hiding the nasty reality...:

 

Current state of the interior:

 

How the engine bay looked when I first got the car:

 

Original S11 stamping!:

 

Immediately after removing the cylinder head, prior to any vacuuming/clean-up - October 2022:

 

Cylinder 3 & 4 Close-up...Yikes!:

 

Broken head gasket:

 

Edited January 15, 2023 by CarlN-NDC

[Los_Control]

Welcome aboard, nice project to start with .... Sounds like you have done your homework. Just remember it is not a running race. To see who finishes first.

Suppose to be a learning process, that you enjoy & do for fun. ..... Some of us old farts do it for mental health reasons.

 

It is a process & enjoy it .....

[chris 48 P15]

hello 

nice car to learn on

parts are available check local auto part stores as well as specialty auto part stores for parts

also use this forum for info 

have fun

 

[Doug&Deb]

Welcome! It’s refreshing to see younger people get into the hobby. You’re in the right place. Lots of knowledge here. You may want to join the national DeSoto club if you haven’t already. Good luck and keep us posted on your progress.

[keithb7]

A hearty welcome Carl! I think I'm gonna like you...Reading, learning and understanding first. Then you put your new found skills to the test. That my friend is a plan. By doing so you are not "hoping" to fix this car. You are "planning" to. A hope, is a just dream without a plan.

 

I suspect you may have watched some of my YT educational videos on these old Mopars. I live here on this site and will happy to help you out where I can. As will many other members here. These cars are so simple, they are fantastic cars to learn all about automotive systems. You can indeed lap valves. You could just have the machine shop cut the right seat angle and install new guides. Then you can do the rest.  Lapping and sealing valves is very rewarding work. The experience gives you insight and feeds your brain. The more work you do yourself, the better you feel. The better you feel, the more new projects you'll take on. The better you understand things on a foundational level. You'll be able to troubleshoot almost any problem. Whether in the garage, or on the side of the road.

 

In terms of the stuck engine, I came into possession of one like you describe. The piston rings rusted to the cylinder walls. I got everything out of the way. I flipped the block over on my stand and used a couple pieces of 1"x1" dimensional lumber and a 3 lb sledge. After soaking both upper and lower parts of the rings with penetrating oil for weeks, I finally took a swing of rye and started pounding the pistons from the bottom side out the top. I know I split up a few pieces of the wood in the process. The job was was a bit of a bugger, but they came out. Done carefully, I can't see this doing a whole lot of cylinder wall damage. You can hone the top of the cylinders above the pistons before you run them out. The damage is already there with the rust. Just don't pound on any rod ends. You could bend them slightly. You want to try and re-use your rods. Mucho $$ to replace the rods with new. Keep in mind, if you look around, 25" block engine cores can be found for cheap.

 

You can rewire that whole car yourself. Make your own harnesses. I did so, in my '38 Plymouth. Fun and again, very rewarding. It will provide excellent training and experience that you'll have for the rest of your life.

 

I started with old Mopars about 2016 I think it was. I learned more about cars in the past 7 years than I probably did the first 30 years of my adult life. I wish I had started way earlier. 22 years old sounds about perfect.

 

I look forward to seeing you work through this car.  Don't be scarce around here. Feel free to ask any questions. There are no dumb questions. Tons of people here to ask for great advice.

 

Keith

 

 

 

 

Edited January 15, 2023 by keithb7

[Marcel Backs]

That car will be beautiful to run around in when on the road. It is definitely a solid old mopar and a very worthwhile model for what you want to do with it. When buying parts for the engine, stick with American made current parts (eg Sealed Power engine parts) or New Old Stock parts. The reproduction replacement parts suffer from many quality issues due to cheapo production methods and inferior materials used at the factories in the eastern hemisphere. Fixing an 80 year old car will give you an extreme rush of accomplishment, especially when you head out on the highway! M  

[Happy 46R]

Welcome aboard and looking forward to those future posts. I like the Desoto look retained by that original paint and the way it sits. You will have a great time and like everyone says you "WILL" enjoy the process! Keep us informed and have a great experience.  Dave

[CarlN-NDC]

@Doug&Deb Thanks for the welcome!  Regarding joining the National DeSoto Club, I joined last April 2022.  I attended the 2022 NDC Convention last year in Altoona, PA.  I made lots of new friends and everyone there was a wealth of knowledge.  I credit many of them for starting me off on the right foot explaining the differences between the semi-auto shifting transmission and the Fluid Drive coupling.  Rather than incorrectly calling it a Fluid Drive Transmission!!

 

I have every intention of attending the 2023 NDC Convention in Chatham Ontario, Canada this year.  Unfortunately, I won't be driving my DeSoto to an NDC Convention any time soon, but it was a fantastic experience last year.  Like many have advised, this is my project car, not a daily driver that I need to put back together to go to work the next day.

 

Carl

Edited January 16, 2023 by CarlN-NDC

[CarlN-NDC]

@keithb7 Thank you for the welcome!  Yes, I've seen your videos!  I know you always say in your videos, you are a shade-tree mechanic, a hack, etc.  Keith, you have no idea how valuable I find them.  No exaggeration, I have watched nearly all of your videos, many of them multiple times.  Your "Introduction To Mopar Flathead Engines" videos, I have watched over and over again, each time picking up some additional detail I missed the times prior.  Then I look through my shop manual and parts book to compare.

 

  I am not a mechanic either.  My day job is as a computer Network Engineer.  I sit behind a desk and computer screen for 10+ hours a day.  When I get home from work, I like to switch off the screens and work on something the polar opposite that has zero computers!  I know, rare for my age.  Fortunately though, due the the nature of computers, they break, glitch, and require updating, which inevitably breaks something else.  So I've gotten quite familiar with the troubleshooting process!  What changed, let's try to narrow down the problem, how many devices is this affecting, was something accidentally unplugged, were updates run?  But I enjoy troubleshooting and fixing things.  From early on, I always took apart old electronics to see how they worked!

 

 

Thank you again!

 

Carl

Edited January 16, 2023 by CarlN-NDC

[Merle Coggins]

Welcome to the ‘family’, Carl,

 

When I got my truck the engine was in worse shape than yours. It was also seized tight. The head had already been removed and there was some concoction of ATF and who knows what in the cylinders. There was also a fair amount of water that had filled them again. My truck also has Fluid Drive and since I couldn‘t rotate the crank I couldn’t get all of the nuts off to detach it. So I laid the engine on it’s side (didn't have an engine stand at the time), removed all of the bearing caps, and slid the crank out the bottom. Once it was out I could easily remove the FD coupling. Then I went to work on the cylinders. I used a wire wheel and a flapper wheel sanding drum to remove as much of the rust scale as I could. I then used blocks of wood and a large hammer to get the pistons out. I first had to drive them down a little bit to get that last bit of rust scale, then I could drive them up and out. As Keith said, don’t beat on the rods to avoid any damage. The pistons will be replaced anyway, so they are sacrificial. 

Once I had the pistons out I turned my focus to the valves. They were also seized tight into the valve guides. The heads and valve seats were also badly rusted. I used my large Channel Lock pliers to grip the cam sprocket and I was able to turn it back and forth a little at a time until all valves had been pushed fully open. That allowed me to remove the camshaft and tappets. Then I could hammer the valves back closed. A couple of valve heads snapped off at that time as I wasn’t being careful to save them. Once closed again I could remove the springs. Then I used a long punch to drive the valves out from the bottom. I took everything to a local engine/machine shop. At 0.030” over bore the cylinders cleaned up enough to be useable. There were still a few small pits in the cylinder walls but it hasn’t effected it’s ability to run. He also replaced the damaged valve seats and guides, decked the block and milled the head.

I reassembled it with new pistons, valves, and etc. It’s been running great for nearly 18 years.  

[JerryinTx]

Welcome Carl!  You have found a great source of information and encouragement for your restoration.  I will be following your journey!

[Art Bailey]

Welcome to the boards! I have the same year and model DeSoto, and though I haven't updated it in awhile, I have a tinkering thread documenting the Incredible Progress I've made in the 3 years it's been sitting in my garage (ha). It's a marathon, not a race, as I keep telling myself. 

 

Looks like you have a good starting point there! If I ever reach the point where I need to rebuild the 237, I'd probably look for an industrial block for a few more cubes...they're around, and not too expensive. 

 

Have fun with the car, and enjoy your stay here...lots of great info not found elsewhere, and lots of fine, highly knowledgeable folks here!

 

Best,
Art

[RNR1957NYer]

Welcome!  You will find many kindred spirits here ready to share their knowledge, Grasshopper!  Let me comment on the aesthetics of your DeSoto - strong looking car, and being black I think you will find it surprisingly easy to clean and polish what’s good, and spot repair and blend in what’s not.  I ended up repainting my ‘41 Plymouth panel by panel as repairs were done with Duplicolor black lacquer - all you need are a few rattle cans of gloss black, several grades of increasingly finer wet sandpaper, and a lot of patience (after you get it running, of course).  Keep us posted!

[SteveR]

Welcome from the Yank in Limmy Land. At 69 years of age, I always wanted to be the owner of an old car when young. Things just didn't work out for me. I am glad it has for you.

[CarlN-NDC]

15 hours ago, Merle Coggins said:

Welcome to the ‘family’, Carl,

 

When I got my truck the engine was in worse shape than yours. It was also seized tight. The head had already been removed and there was some concoction of ATF and who knows what in the cylinders. There was also a fair amount of water that had filled them again. My truck also has Fluid Drive and since I couldn‘t rotate the crank I couldn’t get all of the nuts off to detach it. So I laid the engine on it’s side (didn't have an engine stand at the time), removed all of the bearing caps, and slid the crank out the bottom. Once it was out I could easily remove the FD coupling. Then I went to work on the cylinders. I used a wire wheel and a flapper wheel sanding drum to remove as much of the rust scale as I could. I then used blocks of wood and a large hammer to get the pistons out. I first had to drive them down a little bit to get that last bit of rust scale, then I could drive them up and out. As Keith said, don’t beat on the rods to avoid any damage. The pistons will be replaced anyway, so they are sacrificial. 

Once I had the pistons out I turned my focus to the valves. They were also seized tight into the valve guides. The heads and valve seats were also badly rusted. I used my large Channel Lock pliers to grip the cam sprocket and I was able to turn it back and forth a little at a time until all valves had been pushed fully open. That allowed me to remove the camshaft and tappets. Then I could hammer the valves back closed. A couple of valve heads snapped off at that time as I wasn’t being careful to save them. Once closed again I could remove the springs. Then I used a long punch to drive the valves out from the bottom. I took everything to a local engine/machine shop. At 0.030” over bore the cylinders cleaned up enough to be useable. There were still a few small pits in the cylinder walls but it hasn’t effected it’s ability to run. He also replaced the damaged valve seats and guides, decked the block and milled the head.

I reassembled it with new pistons, valves, and etc. It’s been running great for nearly 18 years.  

@Merle Coggins Thank you for the welcome!  Thanks for sharing the process you went through to get your flathead disassembled!  Your story gives me an additional boost in confidence that I will be able to rebuild my original S11-stamped flathead engine.  Fortunately, my engine was never partially torn apart and then left to sit another few decades before it made it to my hands.  When I pull the oil dip-stick, it is right up to the full line.  Hopefully that is a sign it was decently maintained and none of the coolant/water ever made it into the oil.  Whoever was the original owner of my DeSoto must have taken excellent care of the car prior to the head gasket breaking.  Considering it lived it's entire running life in Worcester, MA.  Which is in the rust-belt, much like here in NEPA (Northeastern Pennsylvania).  While yes it has some rust issues, they shouldn't be insurmountable to repair.  In fact, it still has a set of bias-ply snow tires on it!  So it definitely saw road salt and less than ideal weather/road conditions.

 

  Once I get the engine out and disassembled, I plan on taking some measurements with a telescoping gauge set, micrometers, and a dial bore gauge.  With 118,700 miles on the odometer, I am interested to see if it was ever bored-over back in the day.  I've never used any of those tools I just mentioned, but I want to learn and have some idea of how worn, tapered, or out-of-round the cylinder walls are before I take it to a machine shop so I can have an informed discussion with them.

 

 

Carl

[MarcDeSoto]

Do watch some Keith's Garage videos as he goes over engine rebuilding flatheads very well.  I also have a 48 DeSoto, a business coupe that I've owned for 42 years.  But I'm only now getting the engine started.  The body is off of the frame right now, so I'm anxious to put it back on so I can rewire it and drive it.  Don't make the mistake I did and take the whole car apart or you will have to wait 40 years to drive too!  

[Vin's 49 Plymouth]

Hi Carl and welcome to the best forum ever. I'm also a young member at 49?. You will find the right answers here, if you ask the right questions.

As I always, check out my photos on my profile if you would like. These cars are fun stock or custom!!

 

Welcome.

-Vince

[Bingster]

I did make the same mistake as you did, Marc. I got the restoration fever and started taking off parts, sometimes labeling them and sometimes not.  I did get a good amount of sheet metal restored, however.  I'm waiting for the Spring to start the car with my rebuilt fuel pump.

[andyd]

Welcome aboard from Oz.........a suggestion also is when looking for parts try & work out whether there are some parts that whilst not specifically for your car may fit due to being the correct shape or able to be made to fit.......a good example would be things like the inner/outer rockers.........some maybe listed for a Chrysler but not a DeSoto yet they may have the same overall shape and with some modification will work...........this is purely a suggestion but I've found it a good idea when searching say on the internet to check as many options as far as models searched..........the main thing is to enjoy this experience, as others have said, its no race, Welcome aboard from Oztralia.....andyd  

[Bingster]

I have a '47 DeSoto Custom in the same old black paint patina. I'm torn between repainting it in that old sheen or gloss black. They seem to look more "vintage" like they just stepped out of time with that original paint dullness.

[SteveR]

12 hours ago, Bingster said:

I'm torn between repainting it in that old sheen or gloss black.

That can be the beauty or the dull drums of this hobby. Everyone has a belly button and everyone has an opinion. The fact is it is your opinion that counts. Personally, I would look at the resale of the vehicle. In this case though, I think it would be a 50/50 split. Go with what You like and do a good job. Well, that's my 2 cents worth.

[Bingster]

Well, of course you're right. Then there's the color consideration. It might be better to let the new owner repaint the car.

[Bryan G]

I wish I was as far along in my mechanical abilities at age 22 as you are. I can tell we're a lot alike, but I'm nearly 30 years further down the road, and it took me until last year to pull a head. Much of the joy for me comes from the research, including teaching yourself to do the work yourself. Once you're done, YOU will be the expert. The only work you'd ever have to farm out at that point would be because maybe you don't have a lift or all the tools. A project like this is a great confidence builder. When you do have a mechanical failure, because you've been through the car so thoroughly yourself, you can pinpoint the problem without too much drama. 

 

The engine in my Chrysler didn't look much better than that, but my cylinder walls weren't rusted so bad. That 3-4 head gasket break isn't unusual. I had it happen on a flathead six Ford. My engine was stuck solid, too. The trick that worked for me to get it unstuck was to pull the pan, wheel my floor jack underneath, line it up with one of the center crankshaft throws...and start pumping. Took about 3 pumps, the car started lifting up, then POP! Easier, I think, then trying to beat them out once the engine is out. Worth a try, at least. 

 

These cars are not junk, as you well know. They were above average for their day. You're on a good path, my friend!

[CarlN-NDC]

On 1/17/2023 at 12:06 AM, MarcDeSoto said:

Do watch some Keith's Garage videos as he goes over engine rebuilding flatheads very well.  I also have a 48 DeSoto, a business coupe that I've owned for 42 years.  But I'm only now getting the engine started.  The body is off of the frame right now, so I'm anxious to put it back on so I can rewire it and drive it.  Don't make the mistake I did and take the whole car apart or you will have to wait 40 years to drive too!  

@MarcDeSoto I applaud you for sticking with your 48 DeSoto Business Coupe and not losing interest over 42 years!  Or have some other shiny car catch your eye and you forget about your 48 DeSoto.  I've been reading through a few of your previous threads on here.  You definitely seem to be doing a thorough job!  Maybe our DeSotos will meet someday at an NDC Convention!

 

  My goal is to have a reliable driver quality car.  Mechanically and electrically, I plan to inspect, clean-up, and or rebuild every system in the car.  Brake master cylinder, all 6 wheel cylinders, all hard and soft brake lines, front suspension bushings, a full engine rebuild, the list goes on.  As far as the body goes, I will definitely repair the structural rust fairly early on, mainly thinking of the inner and outer rocker panels.  As for the hole in the rear quarter behind the driver's door, I do want to repair that at some point, but that can wait until it's running and driving.  Maybe I'll try to blend in some black paint after that hole is patched, but aside from that, I don't plan on painting the car any time soon.  As for the chrome, aside from polishing it, I'm happy with the condition it is in currently.

 

  My car will never be a perfect show car or a frame off nut and bolt restoration.  Rather something that I can get in and know it will start...and stop...reliably every time.  Like many have advised, it is not a race, but I do hope to get it running and driving, at least around the neighborhood, in the next few years.

 

Carl