VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1929-1932 Abrupt Engine Dying

I was hoping I would not have to write here for a while only to wish you a Merry Christmas in a couple of months. Anyway, Murphy's Law has hit me.

I was running my '29 tonight going to adjust the idle when it just died with no warning. I started it up right away but then died again within 10-15 seconds.

I check the ignition and I am getting a nice spark at the plugs with my tester.

This time I don't seem to be getting enough fuel at the carburetor.

I removed the brass bowl, float and Viton needle and cleaned them up. I reassembled the above only for it to continue to die after running about 10-15 seconds.

I removed the paper filter from my fuel pump and replaced with a clean screen. Same issue. I am getting plenty of CLEAR fuel in the sediment bowl.

Tomorrow I plan on checking how much fuel is getting to the carburetor. I rebuilt the fuel pump two weeks ago when it was running fairly good. I don't believe that will be the problem.

This Carter carburetor was rebuilt when I got it a few years ago but only installed it a couple of weeks ago.

I believe the problem is at the carburetor. If I am getting plenty of fuel to the carburetor inlet I guess I will remove the carburetor and clean it out. Does that sound like the right path to take?

Thanks for the help.

Bob

What does the engine due just before it shuts down? Cough? Sputter? Pop? backfire? or just quit? If you squirt carburetor cleaner into the carburetor inlet can you keep it running? If you tap on the carburetor fuel inlet fitting can you keep it running? Answers to those questions will help us help you.

Thanks Chipper.

Right before it quits running it drops RPM real fast. Even if I try to accelerate.

No pop, sputter or backfire at all.

I try to give it gas with the accelerator and it tries to pull in a lot of air but dies right away with no luck.

I have not tried the carburetor cleaner at the carburetor while it tries to die. I have also not tried tapping the fuel inlet. I will try those tonight.

I am beginning to wonder since the carburetor sat open in the garage for 5 years before I installed it if there is some bug or something in the carburetor.

I had one carburetor that I rebuilt and sent to a guy in Montana that had an idle problem. I don't know how but apparently a bug crawled into the low speed jet passage and plugged it. All I found was some brown shiny stuff when I ran a drill bit up the passage. Ran great on test run before I sent it and also after removing the bug debris. So even if highly unlikely it can happen.

I am betting on the viton tipped needle sticking to the seat. If there is enough leakage to slowly fill the float bowl using the remaining pressure of the fuel pump the engine will start but die fairly quickly. As I have written before most viton tipped needles don't have enough weight so can be stuck with only a teensy bit of gum or varnish.

Very early in my carburetor rebuilding experience, I found that even after I blew out the needle/seat apparently enough gas remained to glue the needle to the seat. At that time I was storing my rebuilt updraft carburetors upside down. That kept the needle closed. On a few carburetors after storage they would not run when put back on my test engine. I tapped on the inlet and all was good. After that I made stands to store the rebuilt carburetors upright. End of problem.

Yes I understand that blowing out the needle and seat should have removed all remaining gas. Apparently that was not the case. Oh, BTW, both viton tipped and solid metal needles would stick.

As mentioned several times previously, you need to discard the Viton tipped needle and seat and install a metal needle and matching seat to see if that cures your problem. As Chipper mentioned, Viton needles have caused issues in the past.

Great points.

I finally got your hints.

Can someone please send me a PM on where I can purchase the steel needle and matching seat?

If that does not work I may be sending it to get the carburetor rebuilt.

Thanks in advance.

Bob

I went to start the '29 tonight and she fired up without hesitation. The engine idled well for about 5 minutes and accelerated what seemed normal.



I guess I am sold on going with a steel needle and matching seat as soon as I can find one.

Hint hint.

Bob

Check your coil and condenser as well....

Mike

I am not too surprised. That is what I expected once you got the needle from sticking to the seat. Happens relatively often even with all metal needles. As long as the needle is wet with liquid they generally don't stick. That is not 100% either.

Had my '31 Phaeton on recent VCCA Southern Fall Tour in Stephenville, TX. Twice it had spells of not running smoothly. Cleared up after tapping on the fuel inlet of the carburetor in one case. Other decided to "fix" itself before I could stop and whack it again. Otherwise ran well and got 15+ mpg. For those skeptics the speed was determined by a Garmin GPS as my speedometer cable broke a while back.

For you folks that are afraid to drive your older Chevy faster than 40 mph, the engine has cast iron pistons, just like Chevy built them. Only exceeded 55 mph a few times and often as road, terrain and traffic permitted was driving for miles at 50-55 mph.

Thanks 1932Confederate,

I will check.

The coil is brand new. Which does not make it okay. It does have over 6.4 Volts at both coil terminals.

The condenser I replaced a while back but I did buy a new one from FS last week. I may install it this weekend. It just seems to be a pain to reset the little screw on the side of the distributor for the condenser.

I placed one of those spark light testers on my number one plug wire and it was sparking pretty good.

I have new points but have not installed them. Did not feel they needed replaced yet. I could be wrong.

From looking at the carburetor while having the recent dying issues, it did seem to be a lack of fuel issue though.

The funny thing is in a weeks time I went from one extreme (to much fuel, rich to the other extreme (to little fuel, lean). Can both of those be related to the needle/seat and float? Needle stuck closed to needle stuck open?

Did not have time to work on it last night but was happy it started right away and it only shut off because I turned it off after five minutes of running time. That is promising.

Bob

Oh, and by the way Chipper. I did tap the brass bowl a few times during the 5 minutes of running last night. I guess I am getting the full use of my Craftsman screwdrivers handles.

I also sprayed some carburetor cleaner in the carburetor intake every once in awhile hoping she would clear her throat.

Bob

Yes it is highly possible for both too rich and too lean to be an issue with the needle/seat. Depends on the position of needle when it sticks. Tapping on brass bowl might help but tapping on the brass inlet fitting is far more effective. Vibration of the needle is what you want to unstick it.

Gotcha. Thanks.

Bob