[Feared_Futura]

I've been working on my 302 swap since sometime last year. started a new job and it took over (not to mention all my energy). Well thursday i got laid off. (I would like to thank all of you guys who pay taxes). i pulled it in the garage. still with a problem i left off with. my set up is an 87 302 C4 trans. The engine is nothing special. it has been converted to carb with late 60's 2 barrel intake adapted to 4 barrel. 600cfm edelbrock performer. i can get it running but it has to either be wide open or steady fuel. it won't idle. what stumps me is that it seems to be getting too much fuel. is there something i need to adjust on the carb? i know it has 2 adjustment screws (maybe air/fuel mixture) on the front. i'm gonna slap the 2 barrel on if i can get it to fit without a spacer. i think that was my original problem getting it to fit without a spacer. i inserting a vid of it with the 2 barrel on it. it pretty much runs the same with the 4.

well since i don't yet have the post requirement i'll just have to post whore a couple threads and edit it in.

 

[VAMP_77]

do you have the owners manual for the carb? my stang had the 1406 on it, my mont has the 1806 (1406=600cfm, 1806=650cfm thunderjet AVS). if you dont have em i think i got an extra book somwhere.

 

[Feared_Futura]

nope no book. got it from a friend. it was included with the motor. i'm 50% sure it's a performer 600 cfm.

 

[jonmark1985]

The front screws are idle mixture screws.

The procedure I use to adjust carburetors is as follows.

1. Allow the engine to fully warm up.
2. Check for vacuum leaks.
3. Set the initial timing with the vacuum advance unhooked and the line plugged. Reattach vacuum line.
4. Verify correct fuel pressure. If you are feeling ready for the challenge verify/adjust bowl float height.
5. Adjust the Idle mixture screws to optimal setting. This is done by adjusting the screws on the front of the carburetor. Turning these screws in (clockwise) enriches the idle mixture and turning the screws out (counter clockwise) leans the idle mixture. As you lean out the mixture the idle speed will initially start to speed up. Then when the mixture becomes too lean the idle will stumble. Lean out the mixture to obtain highest idle speed possible.
6. Adjust the curb idle screw to optimal setting. This is the screw on the side of the carburetor by the throttle linkage that holds the throttle slightly open at idle. I turn this screw to set the idle speed as low as possible. Sometimes it is necessary to slightly blip the throttle after adjustments to allow the idle linkage to properly rest.

Repeat steps 5 and 6 until lowest idle speed possible is produced. Hopefully you'll have the engine idling around 450 rpm. Then adjust curb idle speed to actual desired speed (usually around 650 rpm). Set your idle speed slightly high, as when you replace the air cleaner the idle speed will slow slightly down.

 

[fastfarmer]

If you go to Edelbrock's website they have all the material from the owner's manual on there.
Two things occur to me; first, I don't know what kind of adaptor your using, but I'd check for vaccum leaks in that area. Second, if the carb was used when you got it it might be dirty, have a float stuck,etc. Holleys seem more prone to that than the Eddys. Of course this is assuming your timing is OK, fuel isn't old or contaminated.

 

[Jonzo77]

just outta curiosity, where is your timing set up? did you rebuild the engine?

 

[VAMP_77]

i'm 50% sure it's a performer 600 cfm.

Check the carb# here....
Edelbrock - Carburetors - Air & Fuel Delivery - SummitRacing.com


FIND the carb# from pics below.

 

[Feared_Futura]

timing set up? you just lost me. It's in time to atleast the extent it should be able to idle. i'm certain it's a carb prob. i'll have to try to get it running by messing with the air fuel mixture screws. STUPID QUESTION>>>>>Why are there 2 screws? wouldn't they have to be set the same.


I've heard some people say to screw them all the way in and then back them out a quarter to half turn. Anyone know what kinda "trick" this is?

 

[Feared_Futura]

The front screws are idle mixture screws.

The procedure I use to adjust carburetors is as follows.

1. Allow the engine to fully warm up.
2. Check for vacuum leaks.
3. Set the initial timing with the vacuum advance unhooked and the line plugged. Reattach vacuum line.
4. Verify correct fuel pressure. If you are feeling ready for the challenge verify/adjust bowl float height.
5. Adjust the Idle mixture screws to optimal setting. This is done by adjusting the screws on the front of the carburetor. Turning these screws in (clockwise) enriches the idle mixture and turning the screws out (counter clockwise) leans the idle mixture. As you lean out the mixture the idle speed will initially start to speed up. Then when the mixture becomes too lean the idle will stumble. Lean out the mixture to obtain highest idle speed possible.
6. Adjust the curb idle screw to optimal setting. This is the screw on the side of the carburetor by the throttle linkage that holds the throttle slightly open at idle. I turn this screw to set the idle speed as low as possible. Sometimes it is necessary to slightly blip the throttle after adjustments to allow the idle linkage to properly rest.

Repeat steps 5 and 6 until lowest idle speed possible is produced. Hopefully you'll have the engine idling around 450 rpm. Then adjust curb idle speed to actual desired speed (usually around 650 rpm). Set your idle speed slightly high, as when you replace the air cleaner the idle speed will slow slightly down.

I understand the procedure but it's kinda hard to let the engine fully warm up

 

[Jonzo77]

actually you want to initially turn them out a turn and a half after getting them just to snug. what you're doing is making the mixture richer as you go out. only turn 1/8-1/4 turn at a time on both.
there are 2 screws because they each have their own bank to work with. both sides will be close, but not quite the same, but just as long as they're close, you should be fine...

 

[Jonzo77]

#5 is backwards... turn right (in)= lean, turn left (out)=rich. isn't it?

either way, follow what it says...

 

[Jonzo77]

can you get it to run around 2-2500 RPM? if so, it won't take long to warm up to NOT...

 

[Pletchaj]

i invested in one of those old fashioned tail pipe sensors that tells me the fuel mixture ... 14.1:1 good to go

 

[Jonzo77]

i invested in one of those old fashioned tail pipe sensors that tells me the fuel mixture ... 14.1:1 good to go

they do help a lot...

 

[jonmark1985]

#5 is backwards... turn right (in)= lean, turn left (out)=rich. isn't it?

either way, follow what it says...

Yes I believe it is backwards. With confirmation I will edit the post. Thanks!

 

[Feared_Futura]

here's the link to the vid of it running crappy with the 2 barrel. couldn't figure out how to just post the vid

[ame="http://www.youtube.com/watch?v=jiVo4TZZNAw"]YouTube - Fairmont 1st Run[/ame]



lol i tried for 20 minutes and it just does it on it's own.

 

[jonmark1985]

Wow, that wont even run at all!

One thing I noticed, whats up with your choke, looked like the plate was moving all over? Do you have the automatic choke hooked up?

Also I would try to retard the timing. The backfires through the carb are usually evident of having the initial timing set way to high.

Finally, how many times have you had backfires? I've had Holley carbs with power valve protection still blow out power valves on good backfires.

 

[Stymees'mont]

Sounds like timing to me as well.

 

[Jonzo77]

just outta curiosity, where is your timing set up? did you rebuild the engine?

didn't i already suggest that?:idea:

 

[Feared_Futura]

i'll try all that once i can afford a new radiator. mine has completely fell apart. i had it out and kicked it over and one of the channels cracked. i went to fix it and all of them where in that shape so it's junk. gotta find one for an automatic without spending a butt load. i thought i heard someone maybe stymee say they found one for mustangs cheap. anybody got any ideas on where to get a cheaper.