Flathead Running rich

Several guys have suggested connecting a vacuum gauge. Have you done it? Just disconnect the wiper vacuum line and connect vacuum gauge to the engine there. Should be a steady reading of close to 20 at idle.
 
Check out Charlie Price from Vintage Speed on YouTube. He has several videos on rebuilding carbs. He also has all the pieces you may need for your carb.
Good luck.
 
I plan on checking vacuum but I am also finishing up a bathroom remodel so I have not had much time to work on the car much.

"Uncle Max" has been great in email communication in the past, though I have not emailed him recently.

The car has been running rich since day 1, but I didn't realize how bad it was until the lurching started and I checked the plugs. Keep in mind, I am a newbie when it comes to cars and engines. I have learned a lot but still have a lot to learn.

I went back through some emails with Max last night from November and he mentioned fuel pressure as a possible culprit.

I do have an after market mechanical pump but I put the spring from my old pump in it to lower the pressure. I checked it back in November and thought it was good, but as I said, I am new to this so its possible I was mistaken.

If y'all think fuel pressure could be the problem, I'll try to check it out this weekend.

I have thought about just buying a regulator from speedway to make sure the pressure is correct.

Brad
 
The problem with too much fuel pressure is that it overwhelms the needle valve that regulates the fuel level in the carburetor bowl. The fuel level gets too high and overflows down the throat of the carburetor which you should be able to directly observe by peeking down into the bores. So, while it is good to know what the pressure is, it is not really needed in order to know whether it's causing a problem - the excess fuel can be observed directly.
 
Uncle Max also sells Stromberg parts. He works for Stromberg and is their technician. He does like to use the input fuel valve that use two balls to shut off the fuel to the float bowl. These valves can sometimes hang up due to dirt in the fuel. Do you have a fuel filter? How about a photo of the engine bay. showing the fuel pump.
 
How did you check your fuel pressure? The fact that you can turn the idle mixture screws all the way in and it continues to run means that excess fuel is being dumped into the engine . . . and about the only place is from the carb. Your plugs look really washed down - which means raw fuel.

Note: If you've been having issue like this for awhile, make sure you change your oil - it probably has a lot of gas in it.

Do you have a quality in-line fuel pressure gauge - after the fuel pump? You may need a fuel pressure regulator . . . and don't buy those cheap chrome looking ones with the dial on top - buy a Holley low pressure regulator and make sure you have a liquid filled pressure gauge AFTER it. You want the pressure to be 1.5 to 2.0 lbs MAX.
 
Last edited:
I'll try to get a picture of the engine bay up soon. I am running a glass bowl fuel pump. The bowl was clean last I checked.

I checked the fuel pressure inline between the fuel pump and carb with a vacuum/pressure gauge. It was back in November I think so I don't remember exactly what it was reading, but I want to say between 2.0 and 2.5 lbs.
 
Do be afraid to look in there while its running. The pops you are hearing could correlate with drips of gasoline coming off the nozzle bars (there should be no drips)
 
Charlie ny said:
#2 and #3 are probably correct, however if the power valve at the bottom of the
acc pump well leaks ( who knows why...it happens ) you will run rich. Max will be here
momentarily.
Charlie
Click to expand...
Hate to highjack the thread but Charlie how can I get one of your distributors for 1953 ford flathead v8 (eab heads) to run dual 94 carbs?
Since I am new, they won’t let me send PM’s.
Any help would be appreciated.
Let me know.

Thank you.
 
Just post a few relevant comments and "hello's" and you'll soon have the required 10 posts. That rule is necessary to weed out the scammers that prey on the folks in the "Swap Meet".
 
BigGameJames said:
Hate to highjack the thread but Charlie how can I get one of your distributors for 1953 ford flathead v8 (eab heads) to run dual 94 carbs?
Since I am new, they won’t let me send PM’s.
Any help would be appreciated.
Let me know.

Thank you.
Click to expand...


Charlie Schwendler <cas5845@yahoo.com>
 
Terry said:
Several guys have suggested connecting a vacuum gauge. Have you done it? Just disconnect the wiper vacuum line and connect vacuum gauge to the engine there. Should be a steady reading of close to 20 at idle.
Click to expand...


A vacuum gauge would also rule out sticky valves also (lurching). The vacuum gauge will tell you a lot about a motor and how you should setup the air/fuel mixure screws on your carb. It's just an old-school engine diagnostic tool and you don't have to plug in your laptop to use it.

If you screwed in both air/fuel idle screws and it did nothing (should have stalled the motor). I'd venture to say you have a vacuum leak. It maybe carb, but it's hard to say without a check.


two things you should do on any motor you own. A compression check and a vacuum check.
 
Last edited:
Thanks Tinker.

Anyone have any idea what the thread size/type might be for the wiper port on my intake manifold? The only thing I can find to fit it is the original nut for the wiper tube which I filled with some solder to close off and use as a plug.

My plans for this weekend are to look for signs of too much fuel pressure and test vacuum(if I can find a fitting for the wiper port) and compression and report back.
 
For what it is worth....from my experience too much pressure will in short order flood
fuel out of the carb, that is only my opinion. From a distance I do believe you have
an internal fuel leak, possibly a faulty power valve. Unless the ignition is actually
letting you down.
Charlie ny
 
I was able to get a little time in the shop yesterday. Fuel pressure is definitely one issue. Running just over 3lbs. I've ordered a fuel pressure regulator from Jegs.

The carb may need to be rebuilt, but I don't think I've eliminated all of the other possibilities yet.
 
You must log in or register to reply here.
Back
Top