hi after a few years of forced neglect i decided to demand time to work on my truck. you know kinda bring it back into order make adjustments etc.

i did a compression check on my engine highest 140 lowest 115 about two of each with 130 or 120 being the norm. ok not great but for now it was in acceptable range or so i was told.

i rearranged my spark plug wires. just to clean up the way they were.

me and the bro in law redid the point gap. ran into trouble then got it running again.

then readjusted the carberator now i have a problem.

until that was done everything checked out ok. now i have a good smooth idle again and i can actually idle down the road. i also can go from idle to wide open throttle in drive it used to stumble. but it has now started to stumble off idle *i think that is it*.
i get the first 1/4 of throttle with good performance. then the last 1/4 is good and the middle half is all stumbly.

i would blame the egr but there is none. i would blame the tranny but it happens when sitting in park.

i am sorry that this is long and even more so if the anser is simple. on a side note i have now conclusivly proven that rap drops your iq * and i had precious little points to start with*. half way through the day or right about the time i started to adjust the carb leaness my wife put on rap and yeah i hate that stuff.

anyway i searched through old posts and read that i could be either old worn distributer or the *i think it's called* accelerator pump. either way i am now outa my element and money so if any one has a way to eliminate one or the other as the source of the problem i would appreciate the help.

 

What kind of carb do you have? Leaky Power Valve comes to mind, but not that many types of carbs have them. Dirt in carb could be another thought.

 

carb is a ford motorcraft 2 bbl 2100 where would the dirt be and would it be easy to clean with out a full rebuild of the carb? also how would i be able to check if that is it?

there aren't any pull your part places around where i live so parts are from stores mostly .

 

According to this pic, the 2100 has a Power Valve:

http://arrc.epnet.com/autoapp/9060/c.../90605G06L.gif

If the diaphragm leaks, your engine will run rich when you don't want it to.

At full throttle (under load), it will be fine, and you can tune out some of the problem at idle, but at part throttle, the engine will probably run too rich.

As far as dirt goes, you would need to completely dissasemble carb, clean meticuously and rebuild. Get a carb kit, probably Ford still has them for about....er......OK, last time I bought a Ford carb kit, it was about $25. I kind of think they may be more now.

Sidenote: Something else, other thna the carb could be the problem, but your description makes it sound carb related to me.

 

thanks for that if it is for sure a carb problem i will replace the carb since if i try to rebuild the carb i will end up replacing it any way. i plan on rebuilding the carb latter to learn how to do it though. i hate to say this but the money in and of it's self is not a problem *the old addage that if money is all it takes to fix a problem then it is not a problem* however wasting money is a problem for me. i know i need to replace both of them eventually but for right now i can only do one and i really need to drive my truck. if i don't drive it i will prolly give up on it and shoot it.

 

Theres 2 different versions of the 2100 this link should help... click on 2 barrel
Ford Carburetor Components


See the rebuild process here
Motorcraft Carb Rebuild - Reviving Ford 1957-69 two-barrel

 

thank you for the links.

 

Did it run fine on the top end before your adjustments? Other than a rough idle ? You mentioned you re-gapped your points... Did you check the dwell on them also ? Did you re -connect the vacuum advance after setting it to proper timing?

On your carb....did you run the Air/fuel mixture screws all the way in (not tight) but lightly, and then back both out 1 1/2 turns as a starting point...then you go back and forth to each one til you reach the fastest idle, then adjust your idle back down Via the idle set screw.... Just my thoughts..

 

hey Russ, sounds like maybe a loose upper distributor shaft bushing?

Jacob, maybe pull the distributor cap and pull back and forth on the rotor in the direction of the points where they contact the distributor cam. See if the shaft is so loose that the points gap changes by a huge amount, even to the point of opening or closing the points.

The thing that is ringing a bell for me is you changed the points. I did that to a stock 360 once, and it stumbled all over the place. Every time I adjusted them, it changed where it stumbled. That, and the vacuum advance moving the points in relation to the shaft, all made for some weird issues.

 

Very well could be Art...Thats simple enough to check...Just put a timing light on it and see if the timing is jumping around at the crank..

 

rebuilding a carb isn't that hard.
parts are like $40 if ya figure in cleaner and gloves.

if ya screw up buy another $14 kit.

 

If it's a carb problem, the accel pump is the most likely cause, not a power valve. You can visually verfity accelerator pump function- just look down the venturis while you open the throttle- you should see spurts of fuel.

I'm with krewat and rapid russ though, nothing you say that you did with the carb should lead to that problem. I'd look carefully at your ignition tuning, take a timing light to it and verifiy both centrifugal and vacuum advance are working, and that your timing doesn't jump around.

 

ok i didn't do the gap by dwell russ but i did do the carb right and all the manuals said it was ok to do the gap with a feeler gauge.

my trucks timing has always been weird with a light so i have done it by ear and feel. the previous owner said something about puting a cam in and had no more info than that. i know some rv cams will cause timing to have to be done 180 degrees off and that is basically where my mark is but there is no pointer there. i found that out when i bought and used a timing light. my bro inlaw yesterday tried to convince me that my wires were on wrong he is a 351 guy. so he re arranged them while i sat back and laughed. it didn't run i put them back to right and it ran and runs strong. but big time part throttle stumble.

 

i went out this morning for kicks and started the truck. it started so well that i took it around the block in idle *i have never been able to drive in idle* it also started with barely any twisting on the key and it stayed idleing right after that only died twice and all 3 starts where just the key no gas *unheard of for this truck* i am mising the warmer set up on my truck so that is why it died no biggie here at least not yet.

however the truck still can't do part idle or sudden wide open throttle. yesterday it did sudden wide open throttle but not today. i would think that it is a fuel starvation from that but if is kinda slowly open it up i get idle vrrooooom vrooom blah blah shack vrooom vroom VVROOOOOOMMM. then on the way back down it is even. and it happens that the dying part is right at the throttle needed to do drive in the city. i would take it to the free way but i have to drive through the city to get there and i have a local cop who don't like my truck. also when i am in gear and i hit the gas it get vro. . . . shake then i have to restart.

would it still possibly be a distributor if this happened only on throttle position regardless of rpm?

thanks for the help.

 

well not fixed yet but identified.

it is the vacume advance. it has died and moved on to a better place. i went out this morning and pulled the vacume line then no more problem. so now i have it timed inbetween the way it was aka smooth and good advance for going down the road.

just wanted to say thanks for the suggestions and information. if ever i can help don't hesitate to ask.