Well, going by what you say, it sounds like you haven't replaced the condenser, the points or the coil!

Condensers -- even new ones -- can go bad, and replacing yours would probably be the easiest things to change. It isn't a bad idea to get a second new one and carry it as a spare.

Coils can break down from heat, so that is another possible source of your woes. These can be quite expensive for the original type; I believe you can find a new 6-volt one at your NAPA dealers, and although it may not necessarily install in the same way as your original one, it can be "made to work" temporarily, so you can determine if that's the problem.

You didn't mention changing the points. However, I'd think that they'd cause a problem even if the car was cold, so this wouldn't explain your problem when the car is warm. Have you not checked these lately, or filed the old ones and checked the gap? You may find other problems when you check yours; for example, the rubbing block might be worn down, causing in improper spark.

I think that the postwar Hudsons used metal timing gears (as opposed to the fiber ones used before the War). Assuming they did, the timing gear could not be a problem.

Only other thing I can think of is the vacuum advance. This would explain why you are having problems when the engine speeds up. I'm a "1930's" guy so don't understand too much about their operation.

Anyway, my guess is that your problem is probably a fairly simple one (if that's any consolation)

One question: Does your car run rough during acceleration when COLD, as well as HOT?

Probably also should have mentioned I found gas on the manifold around thr carb. I'm leaning towards the carb is flooding out for some reason? Although I don't understand why because it has been rebuilt twice!!!!! 🙁

Hard to believe it could fail twice, after two rebuildings. Are you by any chance using an electric fuel pump? Possibly it's got too much pressure.

Of course there's that age-old bugaboo, a stuck needle valve. Have you tried tapping lightly on the carburetor with a hammer, just over the needle valve, to break it loose?

On the other hand, possibly there is not enough gas getting in because of dirt in the line. Checked the filters for debris, lately?

John, I pulled the carb apart, and adjusted the float ever so slightly, seems to be just a bit better. Also, I performed a compression test and the results were as follows starting with the cylinder closest to the radiator... 71, 76, 75, 82, 90, 85, 90, 57...

HI Michael,

I read your post as a kindred soul. I am having exactly the same issue with my 1930 straight 8. When I first start the engine, it runs great. As I drive around, for the first 10-15 minutes it runs and accelerates well. After it warms up, I get the strange stumbling when I try to accelerate.

It was stumbling a lot last night when we went into the ice cream store. After we had our ice cream (and the car had sat for 20 minutes or so) it ran much better.

Have you determined the problem yet? I'm on a mission to figure this out and am glad someone else is having the same trouble, although I'm sorry you have to live through it!

Scott

Scott,
Is your coil up front by the radiator? I had similar problems with my '30 Essex when I first got it going after my rebuild. The car would run fine for 4-5 miles, then, when it got hot, would stumble, hesitate, and eventually stop. Once I let it sit for awhile, it would start up and continue on. One of the guys in the club suggested I move the coil to the firewall. I did that and have not had a problem since. I kept the original coil up front for looks.

My coil is on the firewall. I did see someone else discuss the condenser having trouble with heat. My condenser is on the outside of the distributor up front. I guess I could change it out for good measure.

Thanks for the post!

Scott,
So you can eliminate that one! When my condenser went out, I couldn't even get the car to want to start (it quit on the highway after a long run on a very hot day), so I wonder if it is the condenser. Do you have an electric fuel pump or vacuum tank? That was another issue I went through with symptoms similar to yours.

I have a new fuel pump. My uncle installed it before I got the car. He thinks the stumbling started after he put that on, so I'm wondering about too much pressure. A vacuum tank certainly had very little pressure.

Another question. How fast should I expect to cruise down the highway once I get things sorted?

Scott,
The pump could very well be your problem. There was an electric pump on the Essex when I took possession of it (my grandfather had long ago got rid of the vacuum tank). Long story short, I could never get the thing to run properly until I found an old vacuum tank, fixed it up and installed it on the car. The old Marvel carb just couldn't take the constant pressure from the electric pump.
As far as speed, I usually travel between 35-45 mph. When out on an open highway, sometimes get it up to 50 mph. When I drove it the 45 miles to the National in 2009, I hit 62 mph for awhile on I-75, but didn't want to push it too hard so I dropped back down to 50 most of the way.

Ok! I'm now on the hunt for a vacuum tank! Thanks very much Joe!

Now I'm getting a bit confused.

We started out trying to solve a problem with a 1948 Eight, and ended up working on a 1930 Hudson. What happened?

Did the fellow with the '48 ever get his problem solved?

Sorry, Jon. Should have moved our posts to the early Hudson forum. Although, maybe the man with the '48 got a few ideas or got his problem fixed.