The Ford Barn

Brian SATX · 10-11-2016, 06:55 PM

Stock except modern points/condenser. Starts fine and idles good. When I try to give it gas in the driveway, it back fires and stumbles. Timing is right, points are good. Any suggestions where to go next?

Mitch//pa · 10-11-2016, 06:58 PM

Double check the basics incld fuel condition::
See if your losing spark or fuel... Condenser?
I use an inline spark tester to monitor the spark or carb cleaner to richen it...

Dbbc · 10-11-2016, 07:21 PM

Aloha,
Had a similar issue, as soon I applied some throttle it would miss and die.
It was a condenser issue.

Dick Steinkamp · 10-11-2016, 07:35 PM

Do you drive the car regularly?

Did it just start doing this with no adjustment, repair or replacement of any other part?

If something was changed just before it started doing this, what was it that was adjusted, repaired or replaced?

Tom Endy · 10-11-2016, 08:03 PM

Brian:

Make sure you have a good fuel flow from the tank. Remove the fuel line and see if there is a strong stream with the gas cap off. Next check your gas cap to see if the vent hole is plugged. If you have a repo 30-31 gas cap with a center rivet it can loosen up and the gasket and the large washer can rotate and cover up the vent hole.

Tom Endy

1crosscut · 10-11-2016, 09:15 PM

Sponsored Links (Register now to hide all advertisements)

If you were running stock points I would suggest looking for a failing flexible wire under the movable plate in the distributor. However a back fire is often a symptom of an air leak at the manifold or carburetor. Check to see that the four bolts holding the manifold on are snug and make sure the carburetor is tight to the manifold.

Brian SATX · 10-11-2016, 09:27 PM

Sorry a little more info. Not my car, but a friends. He has not driven for a few months. Good fuel flow, spark at points and coil wire. First time working on it yesterday. Pulled what little hair out and found the fuse holder was bad. Got that taken care of and today trying to work on the backfiring. Timing is good, plugs gapped right, points set right. Going back over tomorrow and not leaving till it is right.

RUNNERBUN · 10-11-2016, 09:51 PM

Sounds like the same problem this poster asked about. Re: Engine stumbles and dies
Turned out to be a blocked Main Jet.
http://www.fordbarn.com/forum/showthread.php?t=203934

henry's 31 · 10-12-2016, 11:41 AM

I would check the condenser first. I had a similar problem and that was the issue. If not check your gas flow.

fiddlybits · 10-12-2016, 03:46 PM

I've found that most carburetor problems........ are cured by fixing the ignition. Points/condenser, possibly coil.

Mark W. · 10-12-2016, 03:52 PM

Quote:

Originally Posted by fiddlybits

I've found that most carburetor problems........ are cured by fixing the ignition. Points/condenser, possibly coil.

But every now and then it really is fuel flow and or the carb...

Next crazy thought is if you have a sticky valve in there.

fiddlybits · 10-13-2016, 06:08 PM

Quote:

Originally Posted by Mark W.

But every now and then it really is fuel flow and or the carb...

Next crazy thought is if you have a sticky valve in there.

yeah, once in a blue moon.

tinkirk · 10-13-2016, 06:41 PM

Quote:

Originally Posted by Brian SATX

Stock except modern points/condenser. Starts fine and idles good. When I try to give it gas in the driveway, it back fires and stumbles. Timing is right, points are good. Any suggestions where to go next?

first pull the carb apart make sure everything is clean and jets and passages are all clear
just had the same little problem on a newly rebuilt carb. found out i had to have the GAV open a whole turn for it to run right.
so i guess thats where i would go first seeing that car sat for a while with more than likely corn gas in it.
good luck
Tinkirk

10-11-2016, 06:55 PM	#1
Brian SATX Senior Member Join Date: May 2010 Location: San Antonio, TX Posts: 821	Runs bad Stock except modern points/condenser. Starts fine and idles good. When I try to give it gas in the driveway, it back fires and stumbles. Timing is right, points are good. Any suggestions where to go next? __________________ Brian SATX

10-11-2016, 06:58 PM	#2
Mitch//pa BANNED Join Date: May 2010 Location: Bucks County, PA Posts: 11,454	Re: Runs bad Double check the basics incld fuel condition:: See if your losing spark or fuel... Condenser? I use an inline spark tester to monitor the spark or carb cleaner to richen it... Last edited by Mitch//pa; 10-11-2016 at 07:36 PM.

10-11-2016, 07:21 PM	#3
Dbbc Senior Member Join Date: Apr 2014 Location: Honolulu Posts: 116	Re: Runs bad Aloha, Had a similar issue, as soon I applied some throttle it would miss and die. It was a condenser issue.

10-11-2016, 07:35 PM	#4
Dick Steinkamp Senior Member Join Date: Apr 2016 Location: Bellingham, WA Posts: 1,163	Re: Runs bad Do you drive the car regularly? Did it just start doing this with no adjustment, repair or replacement of any other part? If something was changed just before it started doing this, what was it that was adjusted, repaired or replaced? __________________ All steel from pedal to wheel

10-11-2016, 08:03 PM	#5
Tom Endy Senior Member Join Date: May 2010 Location: Southern California Posts: 3,131	Re: Runs bad Brian: Make sure you have a good fuel flow from the tank. Remove the fuel line and see if there is a strong stream with the gas cap off. Next check your gas cap to see if the vent hole is plugged. If you have a repo 30-31 gas cap with a center rivet it can loosen up and the gasket and the large washer can rotate and cover up the vent hole. Tom Endy

10-11-2016, 09:15 PM	#6
1crosscut Senior Member Join Date: Feb 2011 Location: Lincoln, Nebraska Posts: 1,909	Re: Runs bad Sponsored Links (Register now to hide all advertisements) If you were running stock points I would suggest looking for a failing flexible wire under the movable plate in the distributor. However a back fire is often a symptom of an air leak at the manifold or carburetor. Check to see that the four bolts holding the manifold on are snug and make sure the carburetor is tight to the manifold. __________________ Dave / Lincoln Nebraska

10-11-2016, 09:27 PM	#7
Brian SATX Senior Member Join Date: May 2010 Location: San Antonio, TX Posts: 821	Re: Runs bad Sorry a little more info. Not my car, but a friends. He has not driven for a few months. Good fuel flow, spark at points and coil wire. First time working on it yesterday. Pulled what little hair out and found the fuse holder was bad. Got that taken care of and today trying to work on the backfiring. Timing is good, plugs gapped right, points set right. Going back over tomorrow and not leaving till it is right. __________________ Brian SATX

10-11-2016, 09:51 PM	#8
RUNNERBUN Senior Member Join Date: Nov 2011 Location: Queensland Australia Posts: 640	Re: Runs bad Sounds like the same problem this poster asked about. Re: Engine stumbles and dies Turned out to be a blocked Main Jet. http://www.fordbarn.com/forum/showthread.php?t=203934 __________________ Adjust your points with gentle blows of a 2 pound hammer Last edited by RUNNERBUN; 10-12-2016 at 02:14 AM.

10-12-2016, 11:41 AM	#9
henry's 31 Senior Member Join Date: Mar 2014 Location: Columbus(Cataula) Georgia Posts: 849	Re: Runs bad I would check the condenser first. I had a similar problem and that was the issue. If not check your gas flow. __________________ Henry' s 31

10-12-2016, 03:46 PM	#10
fiddlybits Senior Member Join Date: Jan 2014 Location: N Illinois Posts: 447	Re: Runs bad I've found that most carburetor problems........ are cured by fixing the ignition. Points/condenser, possibly coil.