The Ford Barn

TCap · 12-17-2012, 03:43 PM

Sometimes when I go to start her up, the carb shoots (not dribble) fuel out the back and all over the exhaust pipe. This is a big concern since I've had to shut her down when the fuel starts to smoke. I try to clean the pipe as much as possible but I still see smoke on start ups after.

Anyone else have this issue?

Clem Clement · 12-17-2012, 04:07 PM

Do some checking on your valves. you may have a stuck open intake valve or a broken valve. A compression check will tell you. Timing ok?

TCap · 12-17-2012, 04:23 PM

I think timing is good, I've set it and it sounds good at idle. I've done compression check, all cylinders came in between 58-60. I've check valves recently but can always check again.

J Franklin · 12-17-2012, 04:53 PM

Might be a sticking valve intermittent problem. Dose it with MMO and see if it continues

CarlG · 12-17-2012, 05:00 PM

Quote:

Originally Posted by Clem Clement

... or a broken valve. A compression check will tell you...

Not always. I had a broken valve last year & the compression check showed normal on that cylinder. The (exhaust) valve was broken below the keeper, and therefore it stayed closed all the time, makingthe compression reading normal or slightly above what the other 3 were.

Clem Clement · 12-17-2012, 05:01 PM

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You are getting compressed air into the intake somehow. With the switch off, The fuel sut off and prefererably the battery off, have a helper hand crank over the engine. Put your gloved hand over the carb intake and see if you can find a position the blows air. Maybe you could use the starter after running the carb empty. Be safe here!

TCap · 12-17-2012, 06:45 PM

had a helper crank engine over by hand while I checked valves. All valves seemed to move fine, but I could only see 4 total. Did the carb intake check, put hand over intake while my brother cranked by hand. Felt some air push out intake and stopped on that spot. Checked valves but not sure what I'm looking for. Feeling really lost right now.

lindy williams · 12-17-2012, 06:57 PM

I think the most likely cause is over choking the engine on start up. Only hold the choke closed for two compression strokes and excess gas will no splash back out of the carb. While cranking the engine over with the starter you can hear the compression strokes if you listen closely.

Purdy Swoft · 12-17-2012, 06:57 PM

I've never had that problem. It just seems that if a valve was sticking that it would cause loss of compression on that cylinder and you would get a dead miss.

BILL WILLIAMSON · 12-17-2012, 07:02 PM

Maybe as simple as your timing is too advanced or you're starting with spark lever down a little too far?? Bill W.

Mikeinnj · 12-18-2012, 11:57 AM

Try swapping out your carb with a known good one and see if it runs ok. If so you have a carburetor problem that needs fixing.

TCap · 12-18-2012, 03:58 PM

Another question that may shed some light on this issue. I'm still having problems with the number 2 and 3 spark plugs running very lean...still white porcelain and number 1 and 4 running a little on the rich side. Now with that said, the car sounds really good. I'm thinking, would an intermitten stuck valve cause both issues? If so, would it be more likely to come from exhaust valve or intake valve sticking? I was only able to see the intake valves when I checked, they seemed to be opening and closing fine. I think MMO may be the way to go and then if needed pull the valve cover off and check the valves.

mstover · 12-19-2012, 08:01 PM

Not sure if this is your problem but I've had the float valve inside the carburetor stick open, flooding the carburetor and causing fuel to pour out the back and onto the exhaust. Normally, a few taps on the outside of the carb jiggles the valve closed, however I did need to replace the valve about 6 months ago. Easy to do.
Mike

AL in NY · 12-20-2012, 08:02 PM

I think you are just over choking the engine. So when the engine doesn't start and kicks backward slightly when stopping, it forces excess fuel out of the carburetor and onto the exhaust pipe. Nothing to worry about. Try choking it less when you start it.

Christoph · 12-21-2012, 08:47 AM

In common , i would more likely have a look onto the carb.
You might cross-check with a proven one, as mentioned earlier.

I had a comparable prob there.
The GAV was loose in the carb .
By turning the GAV to the left , i screwed the complete GAV out of the carb

Its to be seen from outside
Have a look on the carb while letting someone turn the GAV....

Good luck
Christoph

TCap · 12-23-2012, 12:56 PM

so I decided to just start the car as is no mmo added yet. Car starts with no gas shooting out the carb (lightly choking). after 3 mins of running smoke is coming off the inside lower part of the exhaust pipe right before the bend. Not sure what is causing this. I shut it down when it starts to smoke. This has happened two days in a row. I'v cleaned the pipe both times and don't see anything that would burn...no clue

Marco Tahtaras · 12-23-2012, 03:27 PM

Quote:

Originally Posted by TCap

so I decided to just start the car as is no mmo added yet. Car starts with no gas shooting out the carb (lightly choking). after 3 mins of running smoke is coming off the inside lower part of the exhaust pipe right before the bend. Not sure what is causing this. I shut it down when it starts to smoke. This has happened two days in a row. I'v cleaned the pipe both times and don't see anything that would burn...no clue

Do you open the right side of the hood and watch everything as it warms up?

TCap · 12-23-2012, 06:25 PM

Quote:

Originally Posted by Marco Tahtaras

Do you open the right side of the hood and watch everything as it warms up?

Yes

matt92vr4 · 12-24-2012, 12:56 AM

Had this issue yesterday with my dads a. The carb float was not making contact with the needle. The bowl would fill up and than puke out excess gas. We have two extra carbs and swapped out the float with one that was shaped better. Problem eliminated.

BILL WILLIAMSON · 12-24-2012, 01:29 AM

Tcap,
Could it just be some old cooked on oil or something that won't just wipe off. Maybe if you run it longer maybe it will burn off. Lay under the car while it's smokin' to find the origin of the smoke. Does your car run with GUSTO? If not, you may have a partially plugged exhaust, causing the pipe to get hotter than normal & puff off some smoke. Bill W.

12-17-2012, 03:43 PM	#1
TCap Member Join Date: Jun 2012 Location: Connecticut Posts: 31	fuel soaked exhaust pipe on start up Sometimes when I go to start her up, the carb shoots (not dribble) fuel out the back and all over the exhaust pipe. This is a big concern since I've had to shut her down when the fuel starts to smoke. I try to clean the pipe as much as possible but I still see smoke on start ups after. Anyone else have this issue?

12-17-2012, 04:07 PM	#2
Clem Clement Senior Member Join Date: May 2010 Location: Fairfax, VA Posts: 3,393	Re: fuel soaked exhaust pipe on start up Do some checking on your valves. you may have a stuck open intake valve or a broken valve. A compression check will tell you. Timing ok?

12-17-2012, 04:23 PM	#3
TCap Member Join Date: Jun 2012 Location: Connecticut Posts: 31	Re: fuel soaked exhaust pipe on start up I think timing is good, I've set it and it sounds good at idle. I've done compression check, all cylinders came in between 58-60. I've check valves recently but can always check again.

12-17-2012, 04:53 PM	#4
J Franklin Senior Member Join Date: May 2010 Location: Oregon Posts: 5,966	Re: fuel soaked exhaust pipe on start up Might be a sticking valve intermittent problem. Dose it with MMO and see if it continues

12-17-2012, 05:01 PM	#6
Clem Clement Senior Member Join Date: May 2010 Location: Fairfax, VA Posts: 3,393	Re: fuel soaked exhaust pipe on start up Sponsored Links (Register now to hide all advertisements) You are getting compressed air into the intake somehow. With the switch off, The fuel sut off and prefererably the battery off, have a helper hand crank over the engine. Put your gloved hand over the carb intake and see if you can find a position the blows air. Maybe you could use the starter after running the carb empty. Be safe here!

12-17-2012, 06:45 PM	#7
TCap Member Join Date: Jun 2012 Location: Connecticut Posts: 31	Re: fuel soaked exhaust pipe on start up had a helper crank engine over by hand while I checked valves. All valves seemed to move fine, but I could only see 4 total. Did the carb intake check, put hand over intake while my brother cranked by hand. Felt some air push out intake and stopped on that spot. Checked valves but not sure what I'm looking for. Feeling really lost right now.

12-17-2012, 06:57 PM	#8
lindy williams Senior Member Join Date: May 2010 Posts: 335	Re: fuel soaked exhaust pipe on start up I think the most likely cause is over choking the engine on start up. Only hold the choke closed for two compression strokes and excess gas will no splash back out of the carb. While cranking the engine over with the starter you can hear the compression strokes if you listen closely.

12-17-2012, 06:57 PM	#9
Purdy Swoft Senior Member Join Date: May 2010 Location: Alabama Posts: 8,099	Re: fuel soaked exhaust pipe on start up I've never had that problem. It just seems that if a valve was sticking that it would cause loss of compression on that cylinder and you would get a dead miss.

12-17-2012, 07:02 PM	#10
BILL WILLIAMSON Senior Member Join Date: Dec 2010 Location: FRESNO, CA Posts: 12,560	Re: fuel soaked exhaust pipe on start up Maybe as simple as your timing is too advanced or you're starting with spark lever down a little too far?? Bill W. __________________ "THE ASSISTANT GURU OF STUFF"

12-18-2012, 11:57 AM	#11
Mikeinnj Senior Member Join Date: May 2010 Location: Northern New Jersey Posts: 1,262	Re: fuel soaked exhaust pipe on start up Try swapping out your carb with a known good one and see if it runs ok. If so you have a carburetor problem that needs fixing.

12-18-2012, 03:58 PM	#12
TCap Member Join Date: Jun 2012 Location: Connecticut Posts: 31	Re: fuel soaked exhaust pipe on start up Another question that may shed some light on this issue. I'm still having problems with the number 2 and 3 spark plugs running very lean...still white porcelain and number 1 and 4 running a little on the rich side. Now with that said, the car sounds really good. I'm thinking, would an intermitten stuck valve cause both issues? If so, would it be more likely to come from exhaust valve or intake valve sticking? I was only able to see the intake valves when I checked, they seemed to be opening and closing fine. I think MMO may be the way to go and then if needed pull the valve cover off and check the valves.

12-19-2012, 08:01 PM	#13
mstover Member Join Date: Dec 2011 Location: Dayton Posts: 43	Re: fuel soaked exhaust pipe on start up Not sure if this is your problem but I've had the float valve inside the carburetor stick open, flooding the carburetor and causing fuel to pour out the back and onto the exhaust. Normally, a few taps on the outside of the carb jiggles the valve closed, however I did need to replace the valve about 6 months ago. Easy to do. Mike __________________ Michael E. Stover, CPA/ABV Living Life in the Slow Lane 2004 Beneteau 331, 1930 Ford Model A 45-B Coupe www.sailtherapy.weebly.com

12-20-2012, 08:02 PM	#14
AL in NY Senior Member Join Date: May 2010 Location: Southern Upstate New York Posts: 1,160	Re: fuel soaked exhaust pipe on start up I think you are just over choking the engine. So when the engine doesn't start and kicks backward slightly when stopping, it forces excess fuel out of the carburetor and onto the exhaust pipe. Nothing to worry about. Try choking it less when you start it. __________________ AL in NY

12-21-2012, 08:47 AM	#15
Christoph Senior Member Join Date: Oct 2010 Location: Frankfurt am Main in Germany Posts: 671	Re: fuel soaked exhaust pipe on start up In common , i would more likely have a look onto the carb. You might cross-check with a proven one, as mentioned earlier. I had a comparable prob there. The GAV was loose in the carb . By turning the GAV to the left , i screwed the complete GAV out of the carb Its to be seen from outside Have a look on the carb while letting someone turn the GAV.... Good luck Christoph

12-23-2012, 12:56 PM	#16
TCap Member Join Date: Jun 2012 Location: Connecticut Posts: 31	Re: fuel soaked exhaust pipe on start up so I decided to just start the car as is no mmo added yet. Car starts with no gas shooting out the carb (lightly choking). after 3 mins of running smoke is coming off the inside lower part of the exhaust pipe right before the bend. Not sure what is causing this. I shut it down when it starts to smoke. This has happened two days in a row. I'v cleaned the pipe both times and don't see anything that would burn...no clue

12-24-2012, 12:56 AM	#19
matt92vr4 Member Join Date: Dec 2012 Location: Venice, FL Posts: 89	Re: fuel soaked exhaust pipe on start up Had this issue yesterday with my dads a. The carb float was not making contact with the needle. The bowl would fill up and than puke out excess gas. We have two extra carbs and swapped out the float with one that was shaped better. Problem eliminated. __________________ 1929 Model A 1992 Galant VR4 474/1000 2007 Prius 54mpg

12-24-2012, 01:29 AM	#20
BILL WILLIAMSON Senior Member Join Date: Dec 2010 Location: FRESNO, CA Posts: 12,560	Re: fuel soaked exhaust pipe on start up Tcap, Could it just be some old cooked on oil or something that won't just wipe off. Maybe if you run it longer maybe it will burn off. Lay under the car while it's smokin' to find the origin of the smoke. Does your car run with GUSTO? If not, you may have a partially plugged exhaust, causing the pipe to get hotter than normal & puff off some smoke. Bill W. __________________ "THE ASSISTANT GURU OF STUFF"