problems with my "new" carb

[Chillin014]

thanks again.
well the battery charged and the car started. I was able to slowly bring down the idle a bit but it was still very high.
the coolant leak ended up being where the hose connected to the water valve so thats good news.

I had the 1 and 1/2 turn counter clockwise position and was too lazy to try to make the small vacuum hose on my gauge fit on the port behind the manifold so I used the port on the front of the carb. It was reading in the 20 range and seemed to drop as i turned the adjustment screws outwards. I turned them both a good 2 turns from the "Starting position" without hearing or seeing a huge change. so i put the car in reverse to see if it would stall out (it did earlier) and it wasnt going to stall but it had this surging feeling as if i was pressing the gas and letting off. This is probably a sign the carb needs to be rebuilt, dont you think? I mean the surging wouldnt be a timing thing or a fuel thing I dont think.

I am not surprised if it needs to be rebuilt honestly it was really caked in the fuel inlet port. so now that is the new project I guess. But i wonder if the kits at autozone are sufficient or if thats only like a "partial" rebuild.

all data is a free online thing isnt it? I need a carb rebuild guide or something..i'll check edelbrocks site and stuff. I do need a haynes manual for this car or something I just know there isnt a specific one.

derision- i thought freeze plug too but thankfully it is not that.

looks like i'll be buying this
http://store.summitracing.com/partd...839063+4294857013+4294857710+115&autoview=sku
and the floats. doesnt look that complex really...

 

[megaladon6]

i forgot about the freeze plugs--good call
i also forgot to tell you that when you first start the car it will probably be on the fast idle cam. let it run for a couple of minutes then blip the throttle, the idle should drop.
you may have to turn the mixture screws in from the initial 1 1/2 setting. most carbs are set-up so that in (clockwise) is lean and out is rich, there are a few backwards ones. one quick check is to turn the screw out enough so that the engine starts to stumble a hair. rev the engine--if the exhaust blows smoke then it's (very) rich. turning the screws in to the stop should stall the engine from lack of fuel.
if it is on the fast idle cam then the mixture screws won't give you a proper change. so just double check that you're on the standard idle and play with the mix, then double check the timing. do the procedure at least twice. this is a case of every change you make affects the previous changes. (hey adjustments are free---do as many as you can!) if it just won't run right then rebuild the carb.

the rebuild kit comes with instruction. honestly i don't have a clue, it's been 8yrs since i r'blt a carb and that was a single barrel for a slant 6.

what car do you have exactly? haynes usually has every car. the engine details won't be exact if stock is a 305 but the 350 is so similar that you should be good for anything short of a rebuild.

 

[megaladon6]

oh alldata and mtchel on-demand charge for use but sometimes autozone and the like will print up the procedures for you at no charge.
just be warned that at the shop we call them somedata and mitchell no-demand. they can have major blank spots.

 

[Chillin014]

haha.
well...i guess i'll give the tweaking another shot tomorrow then just for sh*ts and giggles.

the mixture screws did not seem to be altering anything like you said. maybe tahts why when i blipped the throttle before it came out of the fast idle cam and stalled out. I'll check it again tomorrow to see if i can get it to do anything but the surging kinda had me thinking it just wasnt working right.

i also forgot to mention that the car gets pretty hard to start once it shuts off...ends up needing to be cranked a bit. I was cranking and opening the throttle linkage at the same time (yes i could reach both lol) and the carb backfired a big fireball before the car started.
timing should be advanced if anything from when i was messing with the distributor.

i have an 82 el camino with a gasoline 350 in it.

 

[megaladon6]

carb backfires are usually from a lean condition or over advanced timing. over advanced timing will aslo cause hard starting--it's firing when the piston is moving up, causing the motor to slow down, instead of at TDC.
if its a stock motor i'd start at 4* BTDC. then when you have the initial adjustments in you can pull the old redneck way of timing. set the timing for the highest idle (don't touch the carb adjustments, they should already be set by the book) and leave the dist hold down just loose enough that you can barely turn the dist. drive the car and adjust the dist for the best power. usually you're advancing it till it knocks then backing off. it's the only way i can time mine out--but i've got a screwy system.
haynes makes a manual for the el camino, there's just 10+ years in one book!
http://www.autopartswarehouse.com/mmp/chevy~el_camino~repair_manual~parts.html

 

[Chillin014]

haha wow i have never seen an elky one..every generation is covered? yikes.
well i wouldnt doubt if my carb is lean AND my timing is too advanced. (in fact i know it is because I adjusted it recently and had to advance it on purpose so it'd run).
i've already messed with the carb adjustments man...the idle and what not. im screwed...I need a tach. I cant set the idle without the proper timing but i cant set the proper timing without the corrrect idle on the carb. who freakin designed this system.

carb backfires are usually from a lean condition or over advanced timing. over advanced timing will aslo cause hard starting--it's firing when the piston is moving up, causing the motor to slow down, instead of at TDC.
if its a stock motor i'd start at 4* BTDC. then when you have the initial adjustments in you can pull the old redneck way of timing. set the timing for the highest idle (don't touch the carb adjustments, they should already be set by the book) and leave the dist hold down just loose enough that you can barely turn the dist. drive the car and adjust the dist for the best power. usually you're advancing it till it knocks then backing off. it's the only way i can time mine out--but i've got a screwy system.
haynes makes a manual for the el camino, there's just 10+ years in one book!
http://www.autopartswarehouse.com/mmp/chevy~el_camino~repair_manual~parts.html

 

[megaladon6]

as long as the idle speed is close you're ok. i used to have the engine warm in gear PARKING BRAKE! and adjust the idle speed down until it started to choke then up 1/4 turn.. start the car once it's cold and see how it is. plus i always have a screwdriver in the car for emergency adjustments.
or you can get the $30 tach from summit 🙂 that's what i did for the monte 'cause my tach showed 3k at idle and an estimated 9k when driving! :shock:
you can guestimate on the timing by listening to the engine and setting to the highest idle by ear.
i think the 2 most important things are not having a lean mixture (that destroys engines!) and not having the idle speed so high that it diesels when you turn it off.

 

[85 Cutlass Brougham]

Just wanted to clarify one thing about the Edelbrock AFB carb: It is a mechanical secondary in how it opens the secondaries via a progressive linkage. However, it uses a counter-weighted air valve door to slow the actual amount of air the engine sees until vacuum overcomes the counterweights. The baseplate of a Quadrajet works the same way but the air valve opens on a Q-Jet against a spring whose tension is adjustable. As far as the carb goes, I would check a few things: There is a little check ball in the main body that sometimes gets lost when it is disassembled. If it is missing, it will not run right ( been a while so I don't remember what it does). You also may have a gunked up passage somewhere due to grit getting in to the carb from the tank of the previous car it was on. I once pulled one of these carbs off a Malibu wagon that had so much crap in the float bowls that I could not remove it all. I think it was run without a fuel filter and without an air filter. I was not able to rebuild it and used it for parts. $25 down the drain, but oh well... win some, loose some.

Coolant leak: Did you change the intake manifold when you changed the carb? It may well be that the rear coolant crossover passage is leaking between the manifold and the head. I have had this happen before and that's why I now use a bead small bead of silicone on both the head and manifold when I change intakes. The reason is that most aluminum intakes are a little pitted in this area and the gaskets may not make up the difference.

Throttle bracket: TCI offers an adapter bracket with proper TV cable geometry. I paid $25 for mine. You will also need the proper mounting stud from Edelbrock for the TV cable attachment to the carb's bellcrank. Figure on another $10 there.

Check your ignition timing too. If you disturbed it, you may not have set it properly when you reassembled the engine. Remember that you want the engine to be at operating temperature with the vacuum advance disconnected and the hole plugged, and the engine at the right idle speed before you finalize it. I would also check the advance weight bushings as they are usually nonexistent on an HEI equipped car due to wear and age.

If this does not solve the carb backfire, check a few more things. Is the power brake boosted diaphragm leaking or the hoses to it disconnected? This would cause a massive vacuum leak and make it run dead lean. Did you disconnect the air injection system but neglect to plug the fitting holes in the manifolds? Header leak? AIR system check valves will also leak air into the exhaust if left open.

 

[SBCregal]

used carb = full rebuild
gasket/rebuild kit shouldnt be too expensive, and well worth it

 

[Chillin014]

the timing was adjusted on the old carb and is advanced more than normal so it would run right.
the leaking is not from the intake manifold, I installed the intake manifold a long time ago and did use the silicone in the corners. i already solved the leaking problem.
theres no vacuum leaks.
Im still looking for the connector studs for the carb and tv cable. looks like I'll need a new bracket too...

im still thinking the carb just needs to be rebuilt. what would cause SURGING?

http://store.summitracing.com/partd...925239+4294839063+4294844417+115&autoview=sku
http://store.summitracing.com/partd...925239+4294839063+4294844417+115&autoview=sku
thats about all i see. hopefully those work
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