idles fine but chokes out when i accelerate

[1966 roadster]

I have a all ORIGINAL 1966 u13. 170cid with the original carb. I was driving, and around 3500 rps the carb hesitated. it only did it three or four times. i new that it was a warning sign so i went straight home. I shut off the bronco let it cool so i could work on it. when I started it back up, it started fine but as soon as i give it any gas it chokes and sputters. I have replaced with NEW.

FUEL PUMP

FUEL FILTER

COIL

PLUGS------- ALL 6 gap set at .034

WIRES--------ALL 6

CONDENSER

ROTOR

POINTS set at .025

DISTRIBUTOR CAP

REBUILT THE CARB

AIR FILTER

Even with all these items replaced it STILL DOSE THE EXACT SAME THING!!!!!!!! Its driving me crazy.

I can start the bronco, let it idle till it wets warm 180 degrees. and still no change. I have removed the fuel cap. NO CHANGE. I have tried to set the gap on the points from .015 (ran like crap) all the way up to .032 ( ran like crap}. AT IDLE I HAVE ADJUSTED THE AIR/FUEL MIXTURE AND HAVE IT WHERE THE ENGINE RUNS SMOOTH. I have tried to adjust the air/fuel mixture while ATTEMPTING to give it throttle but still wont run past idle

 

[Bully Bob]

Welcome 1966..

I can all but guarantee it's the accel. pump..

Peek down the throat of the airhorn while you move throttle by hand. (Eng. off)

You should see a steady stream of raw fuel squirting into the lower part of carb. & into the intake.

Could be a plugged jet as well.

Meaning the carb. is the likely suspect.........

Should that not be the prob. look for a loose wire to the ignition.

 

[1966 roadster]

Welcome 1966.. I can all but guarantee it's the accel. pump..

Peek down the throat of the airhorn while you move throttle by hand. (Eng. off)

You should see a steady stream of raw fuel squirting into the lower part of carb. & into the intake.

Could be a plugged jet as well.

Meaning the carb. is the likely suspect.........

Should that not be the prob. look for a loose wire to the ignition.

WOW!!!! I cant believe you replied so quickly $-) ok im standing here laughing my @$$ off

FIRST where is the accel. pump? you would think that I would know since i rebuilt the carb. BUT I DONT

I"m standing on the passenger side of the bronco looking at the carb. I see the throttle cable, return spring, choke assembly. a little to the right (front of bronco) i see a large bolt head that threads into the side of the carb. NOT THE AIR FUEL ****** vacuum line that runs from the carb to the distributor.

I dont know what this large bolt head shaped thing is I unscrew it while the bronco is running and I can hear it sucking air.

Now on the drivers side. (I think this is it ???) four bolts holding a cover. inside the cover is a diaphragm with a large spring that coils down to a smaller diameter. on the outside of the cover it is connected to the bottom of the bowl and is ran through the base of the carb connected to the throttle plate.

NOTE: when I bought my roadster the vent valve rod was NOT connected. in the summer the roadster is my daily driver and I never had a problem with it being gone. I also own a all original 66 mustang when i bought it 5 plus years ago it to was disconnected. the owner said the valve rod would come out of the top of the carb and the throttle would stick wide open so he took it off. I never had a problem with the mustang.

Sorry I dont want you to hold my hand but i have been fighting this problem for a month now. so you might have to explain it to me like im five or maybe draw a picture /emoticons/[email protected] 2x" width="20" height="20" />

 

[Bully Bob]

Not a problem...., :-B

Believe it or not, I've never had that carb. on mine but you are talking about the accelerator pump ...

The prob. can be the pump diaphram.,

The pump stroke adj.,

dirt in the pump fuel passage

---also other possibilities---

sticking fuel inlet needle.

low fuel level., or float sticking

sucking air somewhere. (either around the accel. pump or the carb. mounting)

I think the thing you un-screwed is the power valve.

Do check for squirting fuel (look'n down the hole) B/4 you take anything appart.

 

[1966 roadster]

Not a problem...., :-B Believe it or not, I've never had that carb. on mine but you are talking about the accelerator pump ...

The prob. can be the pump diaphram.,

The pump stroke adj.,

dirt in the pump fuel passage

---also other possibilities---

sticking fuel inlet needle.

low fuel level., or float sticking

sucking air somewhere. (either around the accel. pump or the carb. mounting)

I think the thing you un-screwed is the power valve.

Do check for squirting fuel (look'n down the hole) B/4 you take anything appart.

Ok i looked down the AIR HORN with the motor NOT running and there is fuel squirting down the air horn.

I called all over the Salt Lake valley and finally found a store who still uses books (napa) they have a accelerator pump with a rebuild kit 4$ for the acc. pump 20$ for the rebuild kit.

 

[Bully Bob]

If it's supplying a steady stream..it's doubtful you need a new accel. pump.. /emoticons/[email protected] 2x" width="20" height="20" />

If it's intermittent, then yes.

If you feel the need to rebuild the carb. (thought you just did this.. ) then the accel. pump should be in the kit.

NAPA is "good"

With a steady squirt in play..., the prob. is internal (carb.) or electrical.

Changing fuel filters is the main cause of debris moving up stream to the carb.

BTW post a pic of your rig(s)

& fill-in your sig. page for future simplified help... B)

 

[1966 roadster]

If it's supplying a steady stream..it's doubtful you need a new accel. pump.. /emoticons/[email protected] 2x" width="20" height="20" />If it's intermittent, then yes.

If you feel the need to rebuild the carb. (thought you just did this.. ) then the accel. pump should be in the kit.

NAPA is "good"

With a steady squirt in play..., the prob. is internal (carb.) or electrical.

Changing fuel filters is the main cause of debris moving up stream to the carb.

BTW post a pic of your rig(s)

& fill-in your sig. page for future simplified help... B)

the carb is only "squirting" fuel once through the throttle cycle. i mean. every time i hand pump the carb it will only give one squirt. if i hold the throttle wide open still only one squirt. not a constant steady stream. it wont just keep putting fuel into the carb. I hope i explain that right

so i got another rebuild kit from napa this kit is different is has way more parts. three round bee bees, two diaprams, 7 gaskets, one power valve, couple o-rings. one large ***** in jet and two float needles must be some sort of universal kit. i used everything in the kit that matched my carb components.

i will get some info and pics posted as soon as i get out from underneath the hood. the may be pics of a burnt bronco in the desert.jk kinda depends on my mood

 

[Bully Bob]

How funny...!!...

Naw., don't get discouraged...it's all FUN.... >

I guess I should have been more clear.....sorry... :-B

"....... carb is only "squirting" fuel once through the throttle cycle"

This is normal i.e. it's a "mechanical" pump..., it only pumps with acceleration...either fr. taking off from stop or from stabbing the throttle at speed. (Main jet supplies continuous fuel flow above idle)

By steady., I meant it doesn't sputter with one stroke.

----(hope the censors aren't listening)----

Anyway...,

".....must be some sort of universal kit."

YES..!

That's a good carb. so stick with it., you're doing fine...!!

If you burn an EB.., "CARMA" will search you out........ /emoticons/[email protected] 2x" width="20" height="20" />

 

[1966 roadster]

How funny...!!...Naw., don't get discouraged...it's all FUN.... >

I guess I should have been more clear.....

"....... carb is only "squirting" fuel once through the throttle cycle"

This is normal i.e. it's a "mechanical" pump..., it only pumps with acceleration...either fr. stop or from stabbing the throttle at speed. (Main jet supplies continuous fuel flow above idle)

By steady., I meant it doesn't sputter with one stroke.

----(hope the censors aren't listening)----

Anyway...,

".....must be some sort of universal kit."

YES..!

That's a good carb. so stick with it., you're doing fine...!!

If you burn an EB.., "CARMA" will search you out........ /emoticons/[email protected] 2x" width="20" height="20" />

yeah im only serious on Wednesday. so i put the carb back on and it did on want to start so i went and got another fuel filter. the type that screws on the carb. and put it on it started right up bad news it still just idles wont rev up.

I rebuilt the carb again because in finding that even though you go to the store and but it "new" it dose not always mean that it works. in four days i have bought 3 rotors and 2 distributor caps before getting it started I dont think anything was wrong with the old stuff just wanting to make sure no gremlins sabotage my dream ride while im not looking.

just like i had to buy another fuel filter. that might have been my fault? so i'm back to where i started. just idling in the garage haha your right its all fun just glad someone out there is willing to help. cant thank you enough s

 

[Bully Bob]

Well then.,

the next suspect is the timing..., the vac. advance., maybe even the timing chain...

My 302 equiped EB did something simular., then quit all together.. The timing chain & gear teeth were toast.

Do you have a timing light...? put it on there & see if the mark jumps around.

"...just idling in the garage."

Keep the door open...! ... /emoticons/[email protected] 2x" width="20" height="20" />

BTW did you strap on some safety goggles & shoot carb. cleaner thru all the 'lil orfices (inside the carb) W/the 'lil straw...??

Maybe some others will chime in ...I may be overlooking something here....

 

[1966 roadster]

Well then.,the next suspect is the timing..., the vac. advance., maybe even the timing chain...

My 302 equiped EB did something simular., then quit all together.. The timing chain & gear teeth were toast.

Do you have a timing light...? put it on there & see if the mark jumps around.

"...just idling in the garage."

Keep the door open...! ... /emoticons/[email protected] 2x" width="20" height="20" />

BTW did you strap on some safety goggles & shoot carb. cleaner thru all the 'lil orfices (inside the carb) W/the 'lil straw...??

Maybe some others will chime in ...I may be overlooking something here....

thats the next thing i was thinking was timing. no i dont have a timing light. i was looking at one today at checker it was like 30$

i will get one asap and try to get this thing fixed.

yeah i have the garage door open in the middle of winter haha.

WHATS THE VAC. advance?

 

[Bully Bob]

Vac adv. is a 'lil rubber hose that runs fr. the carb. vacuum. port, to the distributor.

It advances the timing as throttle is added.

Where's all that exhaust going...? :-&

Chinese auto parts (Auto Z) & many other auto parts rent tools for FREE....maybe even a timing light.

 

[1966 roadster]

thats the next thing i was thinking was timing. no i dont have a timing light. i was looking at one today at checker it was like 30$i will get one asap and try to get this thing fixed.

yeah i have the garage door open in the middle of winter haha.

WHATS THE VAC. advance?

yeah a used about a half can of carb cleaner. one thing i noticed while the carb was torn apart was in the middle of the carb was a rod with a spring attached to the other end on the non spring side of the rod was one of those little bee bees. i wiggled the rod up and down, the spring making it rebound. I did notice it was not smooth, meaning as i wiggled it up it was not comming down as fast as i would have thought it would have. there was plenty of play in the rod it just was not "smooth" but then again I really dont know what im looking for????? any thoughts? i'm getting good at tearing the carb apart maybe i should check that rod again.

 

[1966 roadster]

Vac adv. is a 'lil rubber hose that runs fr. the carb. vacuum. port, to the distributor.It advances the timing as throttle is added.

Where's all that exhaust going...? :-&

Chinese auto parts (Auto Z) & many other auto parts rent tools for FREE....maybe even a timing light.

why am I so dizzy :wacko: ok on my carb its a metal-copper-tin-some kinda metal hard line that runs from the carb to the distributor. i was just out in the death chamber looking at it.

i pulled the tension clamps off the distributor and tried to turn it counterclock wise. well the distributor cap is keyed so thats a no go. so how in the world do you advance or ****** timing?

what if? lets pretend that a few days ago one of those little gremlins broke that hard line right where it connects into the distributor, while he was putting on a new cap and rotor :-& #036; but he cut the line off flush and re attached it back into the ***** would that have anything to do with it running like crap? YEAH YEAH I BROKE THE LINE!!!!!!!! it just came off. promise. its back in the distributor as we speak!!!

 

[Bully Bob]

Death chamber... how funny..!!! h34r: /emoticons/[email protected] 2x" width="20" height="20" />

Some yrs. did use a hard line.....

"...so how in the world do you advance or ****** timing?"

There's a single bolt..holding down a clamp at the very base of the dizzy..., where it goes into the block.

"...would that have anything to do with it running like crap?"

Maybe a 'lil bit.... centrifugal adv. takes over just above off idle.

This is gett'n fun..!! :lol: ... I won't quit if you don't...!!

The B-B's are important...not sure about the rod to which you speak...have to dig my book out if that's a problem...

 

[1966 roadster]

Death chamber... how funny..!!! h34r: /emoticons/[email protected] 2x" width="20" height="20" />Some yrs. did use a hard line.....

"...so how in the world do you advance or ****** timing?"

There's a single bolt..holding down a clamp at the very base of the dizzy..., where it goes into the block.

"...would that have anything to do with it running like crap?"

Maybe a 'lil bit.... centrifugal adv. takes over just above off idle.

This is gett'n fun..!! :lol: ... I won't quit if you don't...!!

The B-B's are important...not sure about the rod to which you speak...have to dig my book out if that's a problem...

ok sweet i will get a timing light and start the process tom. thanks for all your help /emoticons/[email protected] 2x" width="20" height="20" />

 

[roadrunner66]

Did you ever figure out what the problem was. I have the same issue going on with my 66 Roadster.

It chokes down when accelerating. Particularly if shifting from 1st it just dies out.

 

[Bully Bob]

Welcome roadrunner..,

No feed-back fr. '66 roadster for a long while...

However.., the accelerator pump is a good start & it's common for them to crack or harden & fail.