Who plays with Carbs anymore?

[blair_b]

So I've run into the issue of absolutely no one knowing much about carburetors anymore. I can usually toy my way around them, but I've hit a snag.
Recently rejetted the Motorcraft 2150, runs as good as ever but doesn't burn my eyes out anymore- bonus. Since swapping jets I now have issues stalling off the line- remedied by some heavy feathering of the throttle.
Thought it might be timing, perhaps set up for when it ran rich. Messed with that, but no change.
Put a light on it today - 4...

Please login to view full content. Log in or register now.

 

[Jimbog]

Have you check to see if the accelerator pump is working properly. Sometimes if the are stuck it wil not get fuel fast enough and stall.

 

[justified]

Yeah , I have a 2100 on my 4.2L as well. Sounds like your accelerator pump. gives it an extra shot of fuel off idle...change that and the power valve while your at it...kit is cheap...

quote from wikapedia...

if the throttle is suddenly opened, the airflow will increase more rapidly than the fuel flow, which can cause a temporary "lean" condition which causes the engine to "stumble" under acceleration (the opposite of what is normally intended when the throttle is opened). This is remedied by the use of a small mechanical pump, usually either a plunger or diaphragm type actuated by the throttle linkage, which propels a small amount of gasoline through a jet, wherefrom it is injected into the carburetor throat. This extra shot of fuel counteracts the transient lean condition on throttle tip-in. Most accelerator pumps are adjustable for volume and/or duration by some means. Eventually the seals around the moving parts of the pump wear such that pump output is reduced; this reduction of the accelerator pump shot causes stumbling under acceleration until the seals on the pump are renewed.

 

[justified]

BTW, Where did you get jets for that carb?

 

[blair_b]

Thanks for the info guys. Got new jets from this guy: gronk2100@msn.com
His name is Michael Ehrmann, has an ebay site and knows a lot. He sent me a #47 & a #48 - runs great now, no more burning my eyes out and stinking after a drive. It had 56's in it. Cost me $15, but he sent the jets based on my motor and elevation- he really knows his stuff. He's in Colorado, so took a couple weeks to get here.
I guess NAPA has the kit for the Acc Pump and Power Valve?

 

[justified]

The full kit ..if i remember, cost me about $20 a couple yrs ago in alberta...napa should have it. do a rebuild anyways...can't hurt. should take u about an hour... Thx for the carb source info! I will be follwing up on that fer sure...

 

[justified]

BTW, reg your choke. If you still have the electric on it, hook it up to the battery and run a switch to it...it'll only draw what it needs and your factory choke will run as designed. just don't forget to turn off the switch! or...just hook the acc.+ to it. It'll do it's thing...

$.02