1940 Stumbling problem
 

So…….after 6 months of going crazy trying to solve my stumbling problems……..along with a rebuilt carb by Charlie……rebuilt Dist from 3rdgen……..rebuilt Skip Haney Coil and a new Napa condenser……..I finally found that the hose from Fuel Reg to Carb was partially blocked. It’s a fuel hose that has a check valve which does not allow fuel to drain back so it’s easier starting. Apparently the check valve was semi stuck and wouldn’t allow enough fuel to properly flow.

Problem solved and I’m riding again, but now I’ve got almost all new stuff. Life is good in Northern Michigan !

Thx……Mike

Re: 1940 Stumbling problem
 

Ain't these old Fords a barrel of fun?? Glad you found it.

Re: 1940 Stumbling problem
 

Glad your car is up and running again. I've never understood the need for a check valve between the fuel pump and carb...the fuel pump HAS a check valve in it, and the carb cannot drain the bowl because the inlet needle is higher than the fuel level. :confused: Whoever made that line did you a dis-service, Mike! But hey... she's in top shape now.:D

Re: 1940 Stumbling problem
 

I wish I could blame on somebody but I was told it was a good idea so I went with it !

All good…..let’s ride !

Mike

Re: 1940 Stumbling problem
 

A leaky power valve will drain the bowl. It's a common phenomenon and the reason there is so much discussion here and elsewhere about alternative sources for Holley power valves.

Re: 1940 Stumbling problem
 

Tub……..understood. Had a couple of bad ones myself.

Re: 1940 Stumbling problem
 

Robert Shewman makes a flex fuel line from the firewall to the fuel pump with a check valve. He can supply the flex line without the check valve also. He advertises in the V8 Times.

Re: 1940 Stumbling problem
 

Terry …….

That’s where I bought the fuel line with the check valve. It worked great for 7 or 8 years and then it didn’t !

Mike

Re: 1940 Stumbling problem
 

If you are in the water main installation business you will likely find a check valve or backflow valve will fail sooner or later. Less is more.

Re: 1940 Stumbling problem
 

Russ…….well it was later and created a headache ! I had checked and replaced everything else and it never dawned on me to check that fuel line with check valve.

Re: 1940 Stumbling problem
 

Mike 42 just a quick note what fuel are you using in the old girl nothing with ethanol i hope that makes for big problems all the time

Re: 1940 Stumbling problem
 

Another long-held myth? Everyone I know uses regular pump gas in their old cars. All pump gas in the metropolitan area is about 10% ethanol. Never experienced or heard of any problem that could be attributed to the gasoline.

Re: 1940 Stumbling problem
 

Joe……I only use recreational fuel. No ethanol. It costs a bit more but I don’t any more headaches. The check valve fuel line was enough for me !

Re: 1940 Stumbling problem
 

Mike, glad you found a issue. I have used that same line you are refering to by Robert Shewman. Personally if your fuel pump primes well enough I dont think it's needed.

Story time...... I had one on my 1933 and it would stick frequently. All I had to do was tap on it and problem gone. I started running a full bottle of Marvel Mystery oil or Lucas fuel stabilizer in every tank and it never acted up again.

Re: 1940 Stumbling problem
 

35….. with all the problems I had for about 6 months it just never dawned on me to change that line ! After removing and running a regular line the problem instantly went away. It cost me money and time, but problems resolved and I’m riding ! I’ve got new carb, coil and distributor now though !

Thx…..Mike

Re: 1940 Stumbling problem
 

Question, what size bottle MMO?

Re: 1940 Stumbling problem
 

The smallest one I can't remember how many OZ's

Re: 1940 Stumbling problem
 

Every fill up on mine I just take whatever size bottle I have and pour a 3-5 seconds worth every fill up!!!! As my grandfather always said "it does ya good and helps you too!!!!" Incidentally I learned it from my Grandfather as he religiously did that with his 59 VW karman Gihia every fill up!!! My lawn mower gets the same treatment, just not as much volume of MMO, obviously.

Re: 1940 Stumbling problem
 

Does Sea Foam do the same as MMO ?