51 Plymouth only starts with ether

[Bob Pas]

My 51 Plymouth recently will only start with a small amount of ether sprayed in carb. It will start fine for the rest of the day but if I let the car sit for a day or two without starting it won't start on it's own without another shot of ether. Once it starts it runs great. Thinking I should take carb off and rebuild. Any suggestions appreciated

[Rusty_OToole]

Rebuilding the carb can't hurt but I would check the choke first. If it has the Sisson choke they work great but do wear out after 70 years and even if not worn out, need to be adjusted and working correctly.

 

[TerryB]

Yes Rusty, I was thinking that too plus float level might be low making the gas in the float bowl evaporate quickly

[The 55er]

Fresh fuel in the tank, right? Stale 6 month old gas can make for hard starting, happened to me on my Hudson, just a thought. 

[Rusty_OToole]

There is another possibility and that is low compression. A worn engine can be hard to start especially when cold, when warm it starts easier. Chrysler built flathead sixes are foolers. They can be in an advanced state of wear and still start and run with no bangs or knocks, just down on power and hard on oil and gas.

 

I had a 49 Chrysler that would start right up no matter how cold, after a careful tuneup and a new choke.

[marcapra]

When I bought my 48 DeSoto in 1980, the seller kept remarking how smooth the engine ran, and it did.  But I brought my compression tester and checked the compression.  Readings went something like this:  70, 55, 25, 75, 50, 60.  So it was a very worn out engine.  Later, after tearing the engine apart, i found broken rings!  I bored it out 30 mil, now it runs fine.  

[Bob Pas]

Thanks for all the input. I will let everyone know how I make out with it.

[Rusty_OToole]

3 hours ago, marcapra said:

When I bought my 48 DeSoto in 1980, the seller kept remarking how smooth the engine ran, and it did.  But I brought my compression tester and checked the compression.  Readings went something like this:  70, 55, 25, 75, 50, 60.  So it was a very worn out engine.  Later, after tearing the engine apart, i found broken rings!  I bored it out 30 mil, now it runs fine.  

On another board I had some correspondence with a woman who bought a 1941 Dodge sedan. It ran but was sluggish and sometimes hard to start. So she took it to a garage for an overhaul. When they took the engine apart the mechanic could not believe it even ran, let alone drove into the shop under its own power. Not only did it have broken rings and worn valves, it had at least one broken piston. Yet it ran without protest and without any bangs or knocks.

To complete the story, $3000 later she drove home with a rebuilt engine. This was about 5 years ago, so far as I know she still uses the car as her daily driver in Maine, at least in the summer time.

[JACK M]

You keep using staring ether it won't be long until it won't run at all. That stuff is hard on equipment.

I have several cars that need a shot of gasoline down the throat after being parked for a while.

[Bob Pas]

You are right there. I will start using gas instead until i get it figured out. Hopefully by the weekend

[Glen Andrews]

On 12/10/2023 at 4:33 PM, The 55er said:

Fresh fuel in the tank, right? Stale 6 month old gas can make for hard starting, happened to me on my Hudson, just a thought. 

About 10 years ago I wasn't doing much with my restored '38 Chevrolet pick up and it sat a few months with ethanol gas in it, I was doing a lot of Harley riding that summer. When I went to start it I used ether, and it would quit running once I stopped applying the ether. You know what the carburetor looked like inside, so a rebuild was necessary, the ethanol gas apparently ate at the rubber flex hose from the tank to the fuel line, and I found the inside of the intake manifold black and gummy, took it off and soaked it in an acid bath at a machine shop, the intake runners of the head were also black and gummy so I used a lacquer soaked rag to get in there to clean them. A lot of hassle and aggravation that I decided to avoid after this experience. So since then I change the gas in the tank every 8 weeks, I put 4 gallons in and use that to start it up and run it every week or two or to drive around the neighborhood, I put more gas in if going to a show. Luckily I have a country store gas station near me that sells 87 and 93 NON ethanol, so for the last 7 years I've been using that. Any remaining gas I drain out I put into my Tundra's 38 gallon tank and top it off with regular gas. I do prime the carburetor if I let my '38 sit too long, cranking it when dry is too rough on the starter and the battery. I know this sounds like an ordeal to change gas every 8 weeks but sometimes it's like I try to make my life difficult!!! And I usually do a good job of it, but it works for me.

[human-potato_hybrid]

If you live near an airport you can buy 100LL gas which will be excellent fuel for any old car.

 

Some airports also sell 93 E0 for the very small planes.

[Bob Pas]

Thank you

 

[Bob Pas]

I have taken the carburator off and it doesn"t look bad but I have ordered a carb rebuilding kit that should be here in a few days. I am also going to drain the tank and start with all fresh Non ethanol gas. May not get it back together before the holidays but will give a update how I made out. Proably after the holidays. Thanks

[Rusty_OToole]

Don't go by the sheet that comes with the carb kit. They are incomplete and filled with errors. Get the specs from a Plymouth repair manual, Carter repair manual, or MoToR Repair manual. Set it up exactly as specified and it should work perfect.

[Bob Pas]

OK, Thanks. I do have a Motors repair manual

[Bob Pas]

Well gentlemen I am sorry I failed to get back to everyone about my Plymouth starting problem.I drained the old gas and rebuilt the carburetor. What I found was the Pump jet was clogged. When I worked the throttle of carburetor on work bench virtually no gas was coming through. Took the rivet plug out and removed the jet and thourghly cleaned. Rechecked with gas in the carb before I put back on car and now it works fine. Let car sit for a few days and get in and it fires right up. Thanks for everyones input.

[WPVT]

I'm glad it all worked out.

When I have been faced with this same problem, first I crank the engine for 20 seconds. Then, I pump the throttle rod and look to see if there is gas squirting from the accelerator pump. If not, I remove the top of the carb to see if there is fuel in the bowl. If not, then I know the mechanical fuel pump is good enough to run the engine fine once it's started, but not good enough to suck fuel and pump it to the carb at starter cranking speed.  I've run into this situation numerous times on different vehicles that sit for a while in between usage.

Until you rebuild or replace the fuel pump, you can carry a ketchup-type squirt bottle, fill it with gas, and use that instead of ether. 

[TTR]

21 hours ago, Bob Pas said:

Well gentlemen I am sorry I failed to get back to everyone about my Plymouth starting problem.I drained the old gas and rebuilt the carburetor. What I found was the Pump jet was clogged. When I worked the throttle of carburetor on work bench virtually no gas was coming through. Took the rivet plug out and removed the jet and thourghly cleaned. Rechecked with gas in the carb before I put back on car and now it works fine. Let car sit for a few days and get in and it fires right up. Thanks for everyones input.

Glad to read it worked out and no need to be sorry about reporting back, even if not immediately. Most people often don’t have courtesy to do it at all.

Did you by chance ended up checking the compression ?

it should always be one of or perhaps the first things to do when diagnosing any running/starting difficulties in any old/used engine, especially in one without comprehensive maintenance/service records

[Bob Pas]

No I didn't do a compression test.  I should have when I was putting all new plugs in. May take the time one day to check it in all cylinders

[Akstraw]

On 12/11/2023 at 3:20 PM, JACK M said:

 

On 12/11/2023 at 3:20 PM, JACK M said:

You keep using staring ether it won't be long until it won't run at all. That stuff is hard on equipment.

 

I am curious why you would say this.  What would be the mechanism of degradation?

[JACK M]

Starting fluid washes any oil that would be in the cylinders. Should be in the cylinders.

Repeated running without some lubrication between the piston, rings and cylinder walls will certainly result in metal to metal wear.

What you are experiencing is common, you are needing to start the engine to bring fuel from the tank to the carburator.

Lots of guys will install an electric fuel pump to aid in this. Run the electric pump until the carburator fills up then turn it off.

I have a couple of cars that do the same thing, I simply squirt a bit of gasoline where you are using starting fluid.

[Akstraw]

I checked three brands of starting fluid at random (Valvoline, StaBil, and Johnson’s), and all three contain an upper cylinder lubricant.  So I don’t see an apparent risk of damaging the engine from periodic use of starting fluid.  I suppose to be sure one should check their specific brand to verify that it contains such lubricant.