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I am wondering if anybody can help me out. I recently installed an edelbrock 650 cfm performer series carburetor with electric choke on my 87 camaro. The engine is a 305 5.0 litre.

The problem I am having is that when i start it up, the engine just revs really high around 4 - 5 thousand rpm and keeps climbing until the en gine is shut off. I am looking for some pointers on what I can do to make it idle normal.

Any help would be greatly appreciated. Thanks a lot

Dave
 

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489 Lemans
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choke setting

How I do it.
I put my car in the garage overnight at about 70 deg farenheit. With the engine cold. On the passenger side of the carb is a round black plastic disc. It has three screws holding it in place. Loosen the screws and turn it until the choke butterfly closes. Turn it back until its about 1/8 inch open. Tighten the screws. Mark where it is for future adjustment. Push accelerator to the floor once to set choke linkage. Start the car and adjust the fast idle speed to about 2000 to 2500 rpm. You can fine tune it the next time the car is outside in the cold.
 

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elect.chock

Here is a Post I made a while back. May be it will help.Read the hole thing before you delete it.

can't tune chock
Here is something that you might want to take a look at: This got me to thinking because, you said it only dose it in the morning when it was cold out side. In the morning go out to the car and then:
(1) Do not get in the car only to release the hood latch. And do not touch the gas peddle Do not turn the key on.
(2) now you are out side looking in the engine compartment. Remove the air cleaner (be careful to not touch the throttled linkage) With a flash lite look down the throat of the Carburetor (the chock plat should be open wide, don't touch it! Till you later why.) If it is real wet with gas down in the bottom of the intake manifold, then the carburetor has drained down after it set's for a long time. (could be the economize valve leaking) This will cause a hard to start, or at lest a longer time to start because it must pump the gas back in the reservoir of the carburetor. It could also cause it to back fire, wash the cylinder walls down, and May even drain gas in to the crank case. But after you get ti to run for a bit,it must likely will run fine and be normal.
(3) If you did not find any thing wrong as listed above, then:
(a) Get in the car and before you turn the key on, steep on the gas peddle real hard and then release it real quick ONE TIME and no more. Now go back out side and look at the chock plat. Is it closed? ( it should be fully closed) If not then the chock needs adjusted so that it well close when cold and after the gas peddle has released it from its wide open position .( the adjusting screw on the steps of the linkage cam is what the peddle releases)( when warm it should be on the bottom step of the cam, when cold and before you touch the gas peddle it is also in this position. But one hard step on the gas peddle and the chock plat should close tight and the cam adjusting screw will move to the high point of the cam) If this is not the way it works, then you need to adjust it till it does.
(4) Now this is why I said not to turn the key on:
(a) If it has an electric chock, when you turn the key on the element in the chock housing starts to warm up and it get hot real quick. So if you have to crank on the engine for a while to get the gas to the reservoir, the chock is all ready hot and is wide open. And wont start right away. So you pump a little more on the gas peddle and then you got to much gas and it back fires and doesn't run very good till it clears it's self out.
I think electric chocks are a pain. But if you don't actuate the chock plat, even the spring loaded chock wont work right. ------------------------------------------------Just something to think about! ------- Gene Neal
 

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Come Home Safe Soldier
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4 or 5000 RPM's are awful high.There is not a bent linkage or the throttle cable is not sticking somewhere is it.If you mount the cable too far back on the carbs base you will hold the throttle blades open.Check to make sure your throttle is fully seated against the stop when you are inspecting the carb like stated earlier.
 

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RPM to high?

Is there a Throttle return spring? Is it hooked up?Is the throttle peddle working properly? Is the high idle adjusting screw hitting the came lob properly? Is the elect. chock linkage hook up properly?With the engine not running, are the throttle plates Sticking in the throat's?Disconnect the throttle linkage from the carburetor, Does it work all right now?And may be, like he said, the high idle screw just needs adjusted!
Just a few thing to think about!-----Gene Neal
 

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87 Iroc,

to confirm it (probably) is the choke and not the linkage, with the motor off, hold the linkage at wide open throttle and back off completely the second (choke-throttle) adjusting screw that is only visible while holding the throttle open.

when you push the throttle to engage the choke, a cam/sloped shaped piece drops in front of that (choke-throttle) screw.

how far up the cam slope and how far in the screw = more rpm.

there are pretty good instructions in the manual for getting the settings you want (more/less/longer/shorter), I start with less and shorter (blade less than half closed, screw almost not on the cam).
it's trial and error for a few days till you get what your motor and climate wants.

just adjust the plastic cap for blade, bend the linkage for cam, set the second screw for fine adjust, and add a ground wire from a cap screw to engine ground, make sure you have a full 12V to the choke.

never needed, never figured out the measuring with a wire part in the instructions
 
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