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Is the choke working?

S

sscam69

Guest
I had mentioned in a previous forum that i had bought the new holley street avenger. Well I am having some problems during startup. Mainly cold start.

Here is the deal. When I start it up in the morning or after a long period of time the car struggles to stay on. It will idle at 500 rpm. After a warm up period everything is fine, will idle at 800 rpm just as I have set it up. I tuned the carb this morning and changed the place where the electric choke hooks up. I have now placed it on the red wire that hooks up to the distributor just as Vigman had suggested. After tuning it i get 14.5" Hg. I checked the potential across the electric choke with the key turned but the engine off and i get 12V.

My question is, is the choke working? When i was playing with it this morning it idled at 1250 rpm then I pumped the gas and it lowered to the right idle. Is this what is suppose to happen when you cold start the car?

In what position is the butterfly valves suppose to be or the top valve suppose to be during cold start?

sscam69
 
W

wolf_walker

Guest
Usually you should stomp the gas once to set the choke, car fires up, runs at fast idle, the choke holds it there till it opens, releadsing the little idle cam and getting you back to your normal idle speed. Pull the breather, look at the carb top and do the above, tap gas to set choke, it should close, open a small amount when the engine fires, and continue opening as the motor warms up. The electric part is mostly just a heating element to hasten the opening of the choke, not good if the motor isnt warm yet. I never quite understood what was wrong with a bimetalic intake mounted setup, other than the electric one is self contained.
I would bet the OEM's used it for emmisions reasons.
 
S

sscam69

Guest
thanks for the info

I will try it tommorow morning and see how let you know how it works out.

sscam69
 

Carrida

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First of all never take power from the coil,you are reducing the available voltage on the primary side of the coil,find yourself a 12 volt power source that is keyed with the ignition on,you can find this with a test light on the fuse box and then run a wire to the choke.set the choke to be almost closed when you first press the pedal to the floor in the morning,then start the car and adjust the fast idle speed screrw to about 1200-1500 rpm. Normal operation get in car pump the pedal once or twice to the floor start the car idle should come up to 1200-1500 depending on what you set it to after about 30 seconds,lightly tap the gas pedal this will bring the fast idle screw down to the next step on the fast idle cam your rpm should drop to about 1000 and stay there untill the choke fully opens then droping your rpm to normal idle speed
 

vigman

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I disagree

There is GOBS of current available at the power line to the HEI the addition of the choke will add no big load and will not be a detriment to the spark.


Mike
 
S

sscam69

Guest
This can get pretty technical.

I mean theres potential difference which would be your voltage and then there is the current that is used to power components. I know that if it uses an electrical motor it uses current to drive it but if it doesn't such as a light it does not. I am not to sure what the electric choke is composed of but I am understanding its some type of heating element making it a resistor. Current flows in the path of least resistance therefore the choke should not consume much.

As for spark plugs what you are doing is creating a charge of electrons to gather at the tips of the plug when it reaches a certain point it connects hence spark.

Please correct me if I am wrong here. Which to some degree I think I am.

sscam69
 

Carrida

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1974 white ragtop
There is not GOBS of current there , If that is what you do,you dont know what your talking about, never take power from the coil period,the choke is a big resistor,the bi-metalic spring gets really hot and that is why there is a vacum line in it to cool it down
 
W

wolf_walker

Guest
It probibly isnt the best idea, and there are plenty of convenient other palces up there, but I doubt pulling that little current off a stock coil would cause any actuall and noticable harm. That said I wouldnt do it.
 

vigman

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Hmmmm Dont know what I'm doing EH?

What observation/formula do you base your OPINION on? It's obvious that the car runs,and It hasn't blown the fuse. So what are your OBJECTIONS using ohms law or any other science you care to.

Mike
 

vigman

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Sscamm

Do you have the Holley install book... can you post what the electrical spec's & install details.


Mike
 

vigman

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According to the Holley tech support line

@1-270-781-9741

The choke draws less than 1 amp MAX ( when cold)

And the MOST PEOPLE install it the way Sscam69 has it... and Holley thinks it is ok as well...

OR MAYBE THEY AS WELL DO NOT KNOW WHAT THEY ARE DOING?

Carrida.. what is it that you do for a living?


Mike
 

Jack

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agree to disagree ... no bashing

Hey guys:
Someone's probably more correct ... dunno who. But can't we continue this discussion without disparaging remarks & innuendo ... accept hat there will be times we need to agree to disagree? Remember, our community's gentility sets it apart from other forums. Please don't bash me ... I buried my Dad just this afternoon ... I've had a rough day too.
JACK:gap
 

vigman

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Sorry about your Dad Jack

I'm done here.

Mike
 
S

sscam69

Guest
Cool It Guys!

Hold up there guys. Carrida I think you came on a little aggresive and have offended vigman. I have read some of his posts and he does have experience. There is also the science behind it which doesn't lie. Its the basis of my profession, engineering that is. Vigman has done his homework and made his arguement. I do agree that it might not be the best place but until someone tells me of a better source, which I am not aware of at the moment, or have the time to find it I will keep it there.

Which brings me to the question I originally had for this post.
Here is the problem. When I start the car in the morning it doesn't rev at 1200-1500 as wolf had suggested. The first time I pumped the gas to set the choke it did work. This morning it didn't. What could be the problem? I opened the hood to see if the choke wouldn't set. The flap did close a bit but not enough to keep the revs high. It was idling at 500 rpm or so. Now before the butterflys were getting caught on the gasket and I adjusted it so that it was reduced but not completely eliminated. Could the choke have something to do with the butterflys getting caught?

Another sympton, even if the car is warm when I start up and try to take off as I am putting in the clutch the car struggles to stay on and has died several times on me. After I drive it a bit the problem goes away. What could it be? Floats? Fuel Feed?

I have set the idle at 800 rpm and I am running 14.5 inHg.

sscam69
 

Carrida

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Oct 27, 2001
Messages
21
Location
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1974 white ragtop
Again vigman,you cant read it says in all the manuals to hook up the choke to a keyed 12 volt source it does not say to take power from the coil uh uh and it draws 2.3 amps and yes I am a grease monkey and carb and FMU specialist nuff braging hook up your stereo from the coil while your at it man,just cause its easy and convenient doesnt make it right.sscam99 first fix any mechanical bindings,i:e throttle plates, linkage,then adjust the idle mixture screws to achieve the best idle,lil tip use a vacum guage and adjust the mixture screws to get the highest vacum,then set your idle screw and then recheck the mixture screws over and over till you get best idle and highest vacum reading,now for the choke,with engine cold set the choke flap to close with about a 1/4 inch opening,you do this by loosing the 3 screws holding the bi-metalic spring housing and turn acordingly,one way opens it more one way closes it more,now press the pedal to the floor go check the fast idle screw and cam,make sure it is sitting on the cam properly and start the car, you can raise the fast idle speed by turning the fast idle screw that rides on the choke cam,hope it helps you,later
 

Carrida

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Oct 27, 2001
Messages
21
Location
Canada
Corvette
1974 white ragtop
Oh ya I forgot a very important part,make sure your float levels are set right,set them so the fuel is just under the sight hole,if it is set to high it will flood when you shut the car off,and if it is too low it will stumble on turns,holleys are famous for leaking fuel past the needles and seats,I like to use the viton tipped fuel inlets
 
S

sscam69

Guest
I have not tried adjusting the choke itself because there are suppose to be "race ready out of the box". Guess not huh. As for the floats I have not messed with them as of yet but if i have a chance I will check it out tonight. For sure tommorow.

I am trying to do most of my homework and research today so that I can work on my car tommorow. I will also try to find a better source for the electric choke.

Thanks for the suggestions Carrida

sscam69

oh and you and vigman ease up a little.
 

Carrida

Member
Joined
Oct 27, 2001
Messages
21
Location
Canada
Corvette
1974 white ragtop
Hey sscam99,the float setting is the first thing you have to set,if they are set off it throws everything off,after you get it initially dialed in then the fun really starts. Tuning the carb to the engine can take days and can pay off in a big big way.take care and I`ll say sorry to vigman aswell
 
S

sscam69

Guest
Ok Carrida

I didn't have a chance to check the floats after all. But I could not help taking her out for a cruise before I started doing homework.


The choke:
I pumped once, started, then died. I pumped twice then started and held and choked kicked in. She went from 500 rpm to 1500 in 5 min. Pulled her out and didnt stall. I guess I have to pump more to get it set. I will keep trying it to see if it is consistent. That will tell me that I wasn't pumping enough.

The fun part:
Well as i was cruising with my brother I told him that any ricer I saw I would give him a hard time. As I was driving down a main street one passed us going the other way. Here I go turning and fish tailed a little and caught up to him. Revved a little and blasted off! Anyways after pulling hard and reaching 90, full throttle all the way, I eased off the gas hit the brakes to slow down. Heres the question after I eased off and put the brakes the rpm dropped to 450 just barely keeping her alive. She was in neutral as I was doing this. Manual tranny.

Could this have something to do with the float levels?

sscam69
 

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