42 Mercury Sedan Idles Then Dies Video

[signsup]

1942 Mercury Town Sedan. Ran when purchased from Bubba and we took a short ride, 2,3 miles. Gauges do not work, but not overheating. Today, engine starts, idles, then chugs and dies and will not restart. Let sit for 10 minutes and it will start, idle smooth, chug and die. Aftermarket carb and electric fuel pump. I was thinking vapor lock, but two rubber lines to and from carb and not warm to the touch.
Rattle noise in video is loose fan pulley or fan belt running to top block mounted alternator.
I ran some carb cleaner down the throat and no difference. I have removed the aftermarket air cleaner in the video. Throttle cable to dash works, but no choke cable. Wires to carb, so presuming electric choke?


Thoughts as to where to start diagnosis?
https://youtu.be/aAyhVMZAiNc

[mcgarrett]

Always begin with the easy stuff...replace the condenser with a new or known to be good one. Old condensers can sometimes be the Achilles heel of many reliability issues. They can sometimes cause the engine to do what you have described.

[tubman]

You may have to go through 2 or 3 new condensers to find a good one. It's fortunate they're (relatively) cheap.

[hueyhoolihan]

don't seem to be able to get the video to play. does the url really start with "studio"?

[signsup]

Edited the link, works now. Local club member suggested either vapor lock in the fuel pump line or sediment in the tank, suggested rocking the car when this starts and see if it frees up. I'll also add some fresh gas to see if fuel level changes anything.
I am very familiar with condensors acting up on most of my military vehicles it's an ongoing issue. Have found that Blue Streak condensors, if made in Mexico or US have had the best luck. Anything from China is hit or miss with the emphasis being on the miss. Perhaps condensor is heating up and looses effectiveness? Then cools off and car will start? This might explain why, perhaps, after the initial cold start of the day, it runs the longest before an issue, then subsequent restarts have a shorter run time.
I'll play with fuel, then electrical.
Thanks for the suggestions.

[rockfla]

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ALSO, after you do the condenser, don't rule out your coil as it can do the same as the condenser....Once hot its starts to put out irradic spark....Skip Haney in Punta Gorda Fl is the man for those....For insurance and piece of mind knowing, I'd send it to him and have it done....Then you can mark that off your list of "potential" problems from here on out!!! ALSO you mentioned an electric fuel pump....what is the fuel pressure? It should be between 2 and 3 psi. Have you check the voltage to the coil when it dies and you try to restart the car???

[Bob C]

I think it flooding out. Looks like fuel coming out the bowl vent
starting at 0:23 in the video.

[rockfla]

Originally Posted by Bob C

I think it flooding out. Looks like fuel coming out the bowl vent
starting at 0:23 in the video.

Hence, why I mentioned fuel pressure and the existence of an electric fuel pump. Signsup...get a socket and ratchet ready and when it stalls out, pull a plug, you will most likely find it wet!!!!!

[Ggmac]

Definitely looks to be flooding. Another easy test is to check for blocked exhaust, but the flooding of fuel is a giveaway.

[hueyhoolihan]

if not a stuck float needle which is possible for a cars that's been sitting for a while, i might look for a punctured float. (when submersed in very hot water there will be bubbles)

[signsup]

Would you just bite the bullet and get a correct rebuilt carb and air cleaner for this project? Might even consider manual fuel pump. This will never be a museum piece, it will be my U.S. Army Air Corps staff car.

[signsup]

I'm seeing Holly Model 94's out there rebuilt in the $130 range which is a no brainer rather than rebuild this aftermarket electric choke carb that has failed. I started it today and when it died I felt around the carb and feel gas on the outside, so a carb project is on the list. As I do not have a Model 94 core to get rebuilt I need to find one plug and play.

[Bob C]

Originally Posted by signsup

I'm seeing Holly Model 94's out there rebuilt in the $130 range which is a no brainer rather than rebuild this aftermarket electric choke carb that has failed. I started it today and when it died I felt around the carb and feel gas on the outside, so a carb project is on the list. As I do not have a Model 94 core to get rebuilt I need to find one plug and play.

Where are you seeing an electric choke?

[petehoovie]

Originally Posted by Bob C

Where are you seeing an electric choke?

[signsup]

Here is pic of wire running to small condensor shaped cylinder on front of carb. Have no idea what it does or does not do. If the upper butterfly plate is the choke plate, it does not move from cold start to warm up. This plate is connected to a cable that runs to the dash and when I pull it out the carb accelerates and the plate closes, but I'm thinking this is a throttle cable. Today when feeling what moves and what doesn't, the gas pedal linkage rod that connects to the lower part of the carb works in and out and the upper plate and cable do not move. So, maybe the cable at the uper linkeage is choke and it is a manual choke. So, if so, what is the wire connected to? It runs down into a loom so I cannot trace it easily, but presume it just runs to power.
I do not feel any part numbers or manufacturer name on this carb, so I wouldn't even know where to begin to get a kit if I wanted to get this one back in action.

[hueyhoolihan]

without the aid of a clear picture, i would guess that the condenser (if that's is what it is) is mounted on the carb to provide ground and the other end of the wire (not visible in the pic) is connected to the distributor. as there is no physical connection that i can see to anything functional having to do with the carb itself. and IME, electronic choke circuitry needs no condenser.

but i will admit that the manual choke linkage often seen on a carb like this is suspiciously missing as far as i can tell. hmmm.

of course, i can always be wrong and often am.

for a little over a hundred bucks, i bought a cheap holley 94 look-a-like on ebay and swapped it into my '41 flathead with little trouble. whether something similar would work on your car, IDK. but it DID straighten out a few fueling problems i was having.

[petehoovie]

Originally Posted by signsup

Here is pic of wire running to small condensor shaped cylinder on front of carb. Have no idea what it does or does not do. If the upper butterfly plate is the choke plate, it does not move from cold start to warm up. This plate is connected to a cable that runs to the dash and when I pull it out the carb accelerates and the plate closes, but I'm thinking this is a throttle cable. Today when feeling what moves and what doesn't, the gas pedal linkage rod that connects to the lower part of the carb works in and out and the upper plate and cable do not move. So, maybe the cable at the uper linkeage is choke and it is a manual choke. So, if so, what is the wire connected to? It runs down into a loom so I cannot trace it easily, but presume it just runs to power.
I do not feel any part numbers or manufacturer name on this carb, so I wouldn't even know where to begin to get a kit if I wanted to get this one back in action.

[tubman]

The cable referenced is the manual choke cable. It is used to actuate (close) the choke, but has a secondary function to open the throttle a little as the choke is closed. A close look at the linkage on the side of the carburetor should make it apparent how it funtions. Again, this is a manual choke, and requires human intervention 100% of the time. You may be thinking of an automatic choke, that works by itself through bimetallic components or sometimes electrically. Be assured that this choke is not one of those.

I agree that the condenser is for radio interference suppresion, and someone just found a convenient (?) place to mount it. I don't brlieve it came from the factory that way, but I am not an expert in this era vehicles.

Also, that looks like a "garden variety" Holley 94. A close inspection should yield some more definitive information on the carb body. If there's nothing, I agree that it should be replaced, because it is most likely an inferior clone.

[Kens 36]

The cable for the manual choke is clearly in place on the right (passenger) side of the carb. Pulling the choke cable knob out closes the choke, pushing it in opens the choke. You should adjust the cable so the choke is fully open when the knob is pushed all the way in.

The condenser shown was probably put there for radio static suppression, although I'm not familiar with one in that position. It has nothing to do with your manual choke.

Ken

Sorry, Tubman - beat me to it.

[tubman]

No problem. "Great minds run in the same circles".