How To Adjust This Old Carb...

Topic: How To Adjust This Old Carb... (Read 2392 times) previous topic - next topic

How To Adjust This Old Carb...

November 08, 2004, 12:30:29 AM

Well, here in mexico many Cougars/Birds has engines with carbs , if not all of them. Mine had CFI but the previous owner aparently destroy the engine (he solds the car to my father without engine for the equivalent of 380 usd) and we put an old engine and i get a blown head gasket, bla bla bla etc... we put a third engine and now runs good, but has a carburetor i want to get the proper fuel mixture because my spark plugs gets carbon for a rich mix. Its a Motorcraft 2150V 2bbl. Any help for a procedure or tips would be very appreciated. Thanks....

Re: How To Adjust This Old Carb...

Reply #1 – November 08, 2004, 11:23:52 PM

Quote from: MexCougar

Well, here in mexico many Cougars/Birds has engines with carbs , if not all of them. Mine had CFI but the previous owner aparently destroy the engine (he solds the car to my father without engine for the equivalent of 380 usd) and we put an old engine and i get a blown head gasket, bla bla bla etc... we put a third engine and now runs good, but has a carburetor i want to get the proper fuel mixture because my spark plugs gets carbon for a rich mix. Its a Motorcraft 2150V 2bbl. Any help for a procedure or tips would be very appreciated. Thanks....

Finally a topic I know something about.

1a. Accelerator pump. At wide open throttle the pump lever should be set to .015 of an inch (feeler gauge). Undo your throttle return string if your doing this on the car. Have a friend pull back and hold throttle lever wide open as if the gas pedal is floored or tie it down but make sure it's still wide open.

1b. Using a long slot screw driver push down on the pump lever hard and hold while using your other hand measure with a feeler gauge the space between the lever and the pump adjusting nut. If you need to adjust then let go of everything and adjust the nut to get .015. Hold the bottom nut and turn the top nut clockwise to compress spring and make the gap bigger or counter clockwise to make the gap smaller.

3. Float level While car is running. Float level should be to the bottom of the fuel bowl site screws. Loosen lock screw a bit and hold then turn nut clockwise to lower float level or counter clockwise to raise. 1/4 turn makes float move 3/16". You can give the accelerator shot to hurry up the change you made. It may be hard to see the fuel at the bottom of the site plug hole. What I do is nudge the car a bit and if the fuel drips out of the site plug then that's perfect.

4. Idle Set idle at 800 rpm or 1000

6. Mixture screws Turn in until the engine starts to stumble and back out screw 3/4 turn. If your cruising and the car feels like it's surging then richen (turn counter clockwise) the air/fuel mixture screws 1/16" on both sides and go for a drive. Do this until the surge is gone. I know you probably don't have a surge problem but keep this in mind for future problems. Some guys like to turn the screws out (richen) until they get the highest vacuum reading or highest rpm but I think this ends up being too rich. You can smell the fuel at the tail pipes at idle which means your too rich unless your car won't idle unless your on the rich side.
7. Metering Block

To remove metering block:

Remove one of the lower screws that holds the fuel bowl to drain the gas from the bowl (use a pan to catch it) don’t let the gas run on the intake.
Undo the fuel line to the front bowl if your working on the front bowl/metering block..
Pry off the bowl carefully so you don’t damage the gasket.
Remove metering block, careful with the gasket.
Use a wide flat thick screw driver to unscrew the jets.
8. Power valve

If you have to change the power valve then use an adjustable or socket.

Place in a vise with wood on each side of the vise jaws so you don't damage it.
Tighten to the following specs. For power valve with multiple drilled fuel opening, torque to 40-50 inch pounds. For power valve with 2 rectangular fuel openings, torque to 100 inch pounds.

The above is from a manuel. Don't worry about useing a vacuum gauge to set mixture, you can get it failry close with trail and error.
If your car as backfired, even once, it is likley the power vavle is blown. From what you desgibed I would suspect a mixture adjustment is necessary. It wouldn't hurt to check the float height first.

Re: How To Adjust This Old Carb...

Reply #2 – November 10, 2004, 12:34:58 AM

Ok , when i can get the large screwdriver i can do the next step. Fow now, i have the 1a and the 3.-rd step done. Ill do the steps in that order for a correct work. For Now, thank you very much merccougar50.

Re: How To Adjust This Old Carb...

Reply #3 – November 11, 2004, 12:10:43 AM

Ya the order is about right, however AFTER you set the mixture screws you may have to reset the idle. If the carb is in good condition you will find the engine respond to mixture adjsutments noticibly. If in doubt slightly rich is better that too lean. (but not rich enuf to leave noticible deposits on the plugs.

Oh! if the initial adjustments cure the problem, do not even try to remove the metering block and all that stuff about power valves. If tuneing doesn't cure the richness that is the next step.

Re: How To Adjust This Old Carb...

Reply #4 – November 11, 2004, 02:16:48 AM

Ok, i went to the store and i bought the large screwdriver. Tomorrow in the morning ill do the next step. I dont have a tach or the vacuum gauge and ill try by trial and error. Ill keep you noticed with the progress,Merccougar, and thanks again...

Re: How To Adjust This Old Carb...

Reply #5 – November 11, 2004, 02:59:12 AM

that last picture makes me miss Mexico - have visited a couple cities. I've always liked the climate (with exception of the horrendously loud thunder at times) and the vegetation that grows in it

Re: How To Adjust This Old Carb...

Reply #6 – November 12, 2004, 12:56:47 AM

Did you visit mexico ? this photo was taken near the beach in Sinaloa. And if you refer to the thunders at the rain, yes, they rumble our mirrors and doors because the lack of Grounding systems (pararrayos), but is a beatiful town...

Re: How To Adjust This Old Carb...

Reply #7 – November 12, 2004, 01:04:22 AM

That is a beautiful cougar you have there. I'm so envious of the weather in mexico. Right here it is currently snowing and I will have to chisle frost off my windshield tomorow.

If you wanna learn all their is to know about this carb, check out this website I found.

http://home.earthlink.net/~bubbaf250/2150carb/carb02b.html

Re: How To Adjust This Old Carb...

Reply #8 – November 13, 2004, 12:39:26 AM

Wow ! Precious Information ! Thanks For all your help !