1939 Plymouth Coupe P8

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Engine hesitation

So i've been plugging away on the Plymouth and was finally able to take her for the first test drive on Saturday. It brakes nicely and shifts smoothly so i was happy with that. I just drove around the block a few times but my engine isn't running quite right. The engine is the original flathead Six 201 cubic inch with a single barrel carter carb (D6A1 to be exact). Here's the issue:

When i blip the throttle from idle its as if the engine gets no fuel and starts to bog down and want to die. Its almost like the accelerator pump is only kicking in after the pedal is depressed to a certain point. If i gradually depress the throttle the engine revs up smoothly. Its the quick blips of the gas pedal that do her in.

The carb was rebuilt by a friend of mine who's been a mechanic for 30+ years so i'm pretty confident that its together correctly.

As a side note, the engine had the same problem with the "blipping" of the throttle prior to rebuilding the carb. At that time i figured it was the accelerator pump that was acting up so a rebuild was in order.

Im wondering if maybe i need to raise my float level? Its set at the factory spec right now.

Any help will be greatly appreciated.

Thanks,

-Chris
 
So I had posted about my engine troubles over on the "Engine Q&A" section of the forum. with the answers I got there I ended up figuring out it was the vacuum advance that was the issue. I replaced that and she now runs pretty well. Thanks guys.

-Chris
 
Hey Guys,

I havent driven the car for over a month now. Im getting lots of blow by from the oil breather and crank case vent pipe. So the engine isn't running all that strong and the oil smoke that fills up the cabin from the blow by was getting pretty annoying. It would find its way in around the brake and clutch pedal holes in the floor. I had to assure any passenger that the car was not on fire :D. So i'll be doing some engine work this winter.

Im thinking of replacing the original 201 ci flatty with a 218 ci that i have from a 53 plymouth. It was in my 52 dodge truck and ran pretty decent. The plan there is to get it running again and see exactly what state its in before pulling the 201 out. I'm leaning towards the 218 cause it has a little more power (100 hp instead of 82 hp). Plus it should be a direct bolt in swap, they're both the 23 inch blocks.

So i've started working on removing the front sheet metal so i can repair the fenders and do engine work easier. See my next post for an explanation and pics of what i've done.

-Chris
 
Well I've been working on the car lately trying to take the front sheet metal off for some engine work. All the bolts holding it on are extremely rusty. I've had to cut all the bolts holding the running boards to the fenders off and a few that bolt the fender to the cowl. The flange on the rear of the fenders that bolt to the running boards are completely rotted out. On the passengers side, the portion of the cowl directly behind the fender is rusted out. I took some pics to show what im talking about.

Pics 1-4: Showing all of the rusty and crusty areas inside of the fender. Once i get them off the car ill have to rebuild them, as well as repair the rotted running boards (or make new ones).

Pic 5: This is a shot of the inside of the fender. The previous owner must have driven the car through fresh asphalt, as this is an example of the heavy coating on the inside of each fender. This stuff is a pain to try and chip off and was really piled up on the fender flanges seen in pics 1-4. I'm sure this helped rot this area as badly as it did.

Pic 6-7: This is a shot of the Arrow headlight conversion. You can kind of make out the "Arrow" script under the parking light jewel.

Pic 8: Someone was practicing there archery and shot the passengers side of the car right below the windshield. I found the arrow head behind the kick panel on the inside of the car.

Now that i have the rustiest of the bolts removed it should go a bit faster in removing the front end sheet metal.

Thanks for looking,

-Chris
 

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That may be a factory or dealer tar based undercoating inside the fenders. My Lincoln has a lot of it underneath the car and fenders, even the bottom of the hood. On mine, when you chip it off, the metal is pristine underneath.

What was the Arrow conversion light? A turn signal? Kind of fitting with that arrow through the body! :D
 
That may be a factory or dealer tar based undercoating inside the fenders. My Lincoln has a lot of it underneath the car and fenders, even the bottom of the hood. On mine, when you chip it off, the metal is pristine underneath.

What was the Arrow conversion light? A turn signal? Kind of fitting with that arrow through the body! :D

Unfortunately not, the coating was definitely the previous owners doing. I chipped clumps at least two inches thick off the top of the frame inside of the fenders. Also the bottom flanges of the fenders, where they mount to the running boards was covered in a couple inches of asphalt.

Nope the car doesn't have turn signals, those only started on 1941 plymouths (i believe). The arrow conversion headlight was to convert from the square lights that the car came with stock, to a seal beamed round lamp. The small light above the headlight is a parking lamp.

Thanks for the comment,

-Chris
 
I managed to pull the front sheet metal off today. I also realized why the previous owner had put a piece of threaded rod through the engine bay tying both the front fenders together. They must have been separating from the cowl and sagging. So his solution was to pull them tight with the threaded rod. I've attached some pics of the bare front end, and some of the rust issues.

Pic 1: The front end is naked!!! :eek:

Pic 2-4: The cowl area where the fenders bolt to is pretty soft. Its no wonder the fenders where pulling away from the cowl and the previous owner added the threaded rod.

Pic 5-6: The flanges on the fenders that bolt to the running boards are just about totally gone.


Thanks for lookin',

-Chris
 

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Man... that's a beautiful old gal! Gonna make an awesome cruiser!!! [cl

BoB

Thanks a lot Tripper! She was a blast to drive the few times i got to this fall. I can only imagine it'll be even more fun when the engine is running right and at full power. The goal is to have her road worthy again and painted all black by this spring. Should be doable, but i've got plenty of work this winter.

-Chris
 
Interesting in regards to the headlight conversion. I have been watching this thread and never noticed that. Here is a pic for comparison.
Rust on old cars is like rot in old wooden boats. You may not see it.But it's always there.
Torchie.
 

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Interesting in regards to the headlight conversion. I have been watching this thread and never noticed that. Here is a pic for comparison.
Rust on old cars is like rot in old wooden boats. You may not see it.But it's always there.
Torchie.

Thanks for posting that pic of the original styled headlights. I like the round ones better than the square. So i'm glad my car has the conversion. When i bought the car i didn't even notice it.

Yea, luckily the rust repair shouldn't be all that bad. At least then i'll know the fenders are securely mounted to the cowl.

-Chris
 
I think i mentioned before that the car had lots of blow by and oil coming out of the oil fill pipe. My plan was to pop the head off and take a look inside, so i started this. I took off the head and dropped the oil pan to look at the bottom end. Well i found quite a bit of sludge in the oil pan, there was at least 1 inch of crap accumulated at the bottom (Pic 1, 2). I then peaked at the bottom end and it also looks pretty dirty in there (Pic 3, 4, 5). I closely examined the cylinder bores and found that a couple of the cylinders have some pit corrosion in the wall (Pic 6). They look deep enough to where the bores would need to be machined to get a nice sealing surface for the rings.

-Chris
 

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Heres a few more pics of the top side of the engine. Those valves sure do look funny colored to me? This is my first time doing engine work like this so any helpful hints as to what the valve color might be telling me is appreciated.

The plan was to try and get the engine back to decent running order without pulling it out of the car. Im thinking it might be past that point judging by what i've seen so far, opinions? So my next idea was to swap in the 218 ci that came out of my '52 Dodge Truck (it was actually from a '53 Plymouth car). The engine ran half way decently a couple years ago when i took it out of the truck. I will need to get it fired up and figure out what kind of health its in before actually putting it in the car.

Thanks,

-Chris
 

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I'm certainly no expert, but ...

The reddish color would seem to indicate that there has been water, or at least moisture getting to those valves, maybe through a worn head gasket or simply from sitting? The sludge in the oil pan is not so bad, and is not a brownish color, so would indicate that there was no water in the oil. That's a good thing!
 
Those cylinders look bad, probably need a .030 bore to clean up. Probably sat for years without being cranked. The valves look pretty normal for an engine that burned leaded gas most of its life. Oil pan looks like the oil wasn't changed very often, lots of collected sludge from years of neglect. Probably ran single weight non detergent oil, too.
 
Thanks for the comments AZRodDave and Bamamav. I guess my suspicions where correct then, the engine will need to go to the machine shop. Im not 100% sure which route ill go yet. Im still going to see what condition my '53 Plymouth 218 ci is in, if thats not healthy either then i'll get the original engine rebuilt. I'd like to avoid the total rebuild route cause of the cost but at least that way i'd have a fresh trouble free engine for lots of years. Decisions, decisions..... :confused:

Either way the engine needs to come out of the car. So i started removing the floor pans. I thought it would be an easy job but every screw had to be cut off (thank you Dremel). One half is out, next will be the toe boards.

Thanks for looking,

-Chris
 

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I was able to get a little bit of work done this weekend. I removed the toe board, which required cutting the head of almost all the screws off. I then took it over to the bench and heated the areas where the cut off screw was so that they could easily be removed. Then i chased all the threads with my 1/4-20 tap and was able to save each threaded insert.

I also had to do the same heating, screw removal, and thread chasing on the chopped off screws that where left behind in the car. I was able to save all those threaded inserts to. I sure was glad to be done after having to do about 15 of them. At least i wont ever have to fight the floor this bad to remove it. When i re-assemble ill be sure to use 1/4-20 hex head cap screws and plenty of anti-seize on the threads. I wish the previous owner had thought of that.

Thanks for looking,

-Chris
 

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That is some painfully slow work, but it looks like you got that portion whipped, it's always good when you can clean up nice new holes for your fasteners to easily go into on the next go around.
 

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