motor runs rich plug are black soot

surfsup · 01-04-2005, 08:32 AM

Cars running rich, ran rich when I bought it, replaced the plugs thinking maybe they where wrong, adjusted the carb that was out but it stills running rich, plugs are black, carb is adjusted correctly, timing is right, not to sure if anything has been done to the motor except for an 3 angle valve job, what’s causing this ??? Do I need a different heat range ?? Motor specs.. 86 block, 85 heads with 3 angle valve, stock Holley carb, no air pump, stock ignition, egr not connected, air tubes to h pipe plugged.

Dark_5.0 · 01-04-2005, 11:35 AM

Make sure the car has the correct spark plugs.

I bought some that the threads were too short on and my car ran pig rich. I bought the correct longer thread plugs and the problem was solved.

westridez · 01-04-2005, 01:25 PM

Quote:

Originally Posted by surfsup

Cars running rich, ran rich when I bought it, replaced the plugs thinking maybe they where wrong, adjusted the carb that was out but it stills running rich, plugs are black, carb is adjusted correctly, timing is right, not to sure if anything has been done to the motor except for an 3 angle valve job, what’s causing this ??? Do I need a different heat range ?? Motor specs.. 86 block, 85 heads with 3 angle valve, stock Holley carb, no air pump, stock ignition, egr not connected, air tubes to h pipe plugged.

i would say its got to be your carb

Jeff Chambers · 01-04-2005, 02:32 PM

How do you know the carb's adjusted correctly? You have deactivated much of the smog equipment and are running heads that didn't come on the motor, so its not inconceivable that the carb doesn't need re-jetting and/or a different power valve. I'd step down two jet sizes, drive it for a while and the re-assess rich/lean conditions.

Rev · 01-04-2005, 04:06 PM

My bet is that there's something wrong in the carb. A leaking needle and seat in the secondary bowl, too high float level, or a leaking power valve can cause that pig rich condition. Sooty black plugs and black smoke mean a very overly rich condition. All that extra fuel has to be coming from somewhere. Just my thoughts.

Rev

surfsup · 01-04-2005, 06:06 PM

I adjusted the carb with a tach and dwell meter, turned the screws in until the motor started to idle down then I turned the screws until I got the highest and steady reading on the tach and dwell, there is no black smoke coming from the exhaust you can tell from the smell it’s to rich and the plugs are black not oil,,this power valve where is it in the carb outside the carb??

grey88gt · 01-04-2005, 09:52 PM

I agree with all the above replys. The power valve is inside the carb. behide the front float bowl assy and metering block.

surfsup · 01-07-2005, 12:12 PM

well for get about the power valve it broke apart when i tried to unscrew it i guess i have a little work ahead of me

grey88gt · 01-07-2005, 11:21 PM

Oh no is part of the vavle stuck in the carb?

surfsup · 01-08-2005, 07:19 AM

yes part of the valve is stuck the threaded part and a small peice of the valve is stuck to the plate

01-04-2005, 08:32 AM	#1
surfsup Registered Member Join Date: Sep 2004 Location: jersey Posts: 147	motor runs rich plug are black soot Cars running rich, ran rich when I bought it, replaced the plugs thinking maybe they where wrong, adjusted the carb that was out but it stills running rich, plugs are black, carb is adjusted correctly, timing is right, not to sure if anything has been done to the motor except for an 3 angle valve job, what’s causing this ??? Do I need a different heat range ?? Motor specs.. 86 block, 85 heads with 3 angle valve, stock Holley carb, no air pump, stock ignition, egr not connected, air tubes to h pipe plugged.

01-04-2005, 11:35 AM	#2
Dark_5.0 Registered Member Join Date: Apr 2001 Location: Staging lane Posts: 4,337	Re: motor runs rich plug are black soot Make sure the car has the correct spark plugs. I bought some that the threads were too short on and my car ran pig rich. I bought the correct longer thread plugs and the problem was solved. __________________ 92' LX-Big brakes, Lots and lots of suspension, GT40X heads, Ported cobra intake, stock cam, Vortech SC trim. 00' Lightning-Stock 88'CRX-13 second ego killer

01-04-2005, 02:32 PM	#4
Jeff Chambers Moderator Join Date: Aug 2000 Location: Milan, OH Posts: 2,699	Re: motor runs rich plug are black soot How do you know the carb's adjusted correctly? You have deactivated much of the smog equipment and are running heads that didn't come on the motor, so its not inconceivable that the carb doesn't need re-jetting and/or a different power valve. I'd step down two jet sizes, drive it for a while and the re-assess rich/lean conditions. __________________ Jeff Chambers 1990 Mustang GT 10.032 Seconds / 137.5 MPH 14-time Street Warrior World Record Setter CRT Performance 2001 Tropic Green Mustang GT - 12.181 / 113.2 MPH 2002 Ford F-250 Crew Cab 7.3l Power Stroke - 17.41@77.2 "There's nothing boring about a small block automatic shifting gears at 9400 rpm!"

01-04-2005, 04:06 PM	#5
Rev Registered Member Join Date: Nov 1998 Location: Houston, Tx. Posts: 3,887	Re: motor runs rich plug are black soot My bet is that there's something wrong in the carb. A leaking needle and seat in the secondary bowl, too high float level, or a leaking power valve can cause that pig rich condition. Sooty black plugs and black smoke mean a very overly rich condition. All that extra fuel has to be coming from somewhere. Just my thoughts. Rev __________________ '66 Coupe, 306, 350-375 HP, C-4, 13.07 e.t., 104.8 mph, 1/4 mi. O.B.C. #2 '66 coupe

01-04-2005, 06:06 PM	#6
surfsup Registered Member Join Date: Sep 2004 Location: jersey Posts: 147	Re: motor runs rich plug are black soot I adjusted the carb with a tach and dwell meter, turned the screws in until the motor started to idle down then I turned the screws until I got the highest and steady reading on the tach and dwell, there is no black smoke coming from the exhaust you can tell from the smell it’s to rich and the plugs are black not oil,,this power valve where is it in the carb outside the carb??

01-04-2005, 09:52 PM	#7
grey88gt Registered Member Join Date: Feb 2004 Location: Skiatook, Oklahoma Posts: 193	Re: motor runs rich plug are black soot I agree with all the above replys. The power valve is inside the carb. behide the front float bowl assy and metering block.

01-07-2005, 12:12 PM	#8
surfsup Registered Member Join Date: Sep 2004 Location: jersey Posts: 147	Re: motor runs rich plug are black soot well for get about the power valve it broke apart when i tried to unscrew it i guess i have a little work ahead of me

01-07-2005, 11:21 PM	#9
grey88gt Registered Member Join Date: Feb 2004 Location: Skiatook, Oklahoma Posts: 193	Re: motor runs rich plug are black soot Oh no is part of the vavle stuck in the carb?

01-08-2005, 07:19 AM	#10
surfsup Registered Member Join Date: Sep 2004 Location: jersey Posts: 147	Re: motor runs rich plug are black soot yes part of the valve is stuck the threaded part and a small peice of the valve is stuck to the plate

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