Carburator problem?

[tealrabbit]

Hi

I drive a -85 camaro iroc 305. Lately the car has been running worse and worse. It is hard to start. First time I try it never starts and second time I need to give it a lot of gas for it to start. Sometimes it takes several tries. When I do get it started I need to give it a lot of gas at first. It will let out a big cloud of almost black fumes but if I don't do this it runs really bad. Even after I do this it doesnt run good. It idles at low rpm and not sounds a bit sputtery.

I've had it for 6 months and it's always been a bit hard to start but only lately has it begun to drive bad. I left it at a mechanic a few months ago and they said it had a bad carb but wanted 800$ to fix it which I know is way to high.

Is it the carb causing all this?


Really appreciate any help.

Thanks

Jakob

[4onFloor]

you sure this is carbed, or is it tuned port?
but anyway, ya might have a plugged pcv valve.

[chevydrummer76]

I had that problem a while back, it ended up being a vacuum leak.

[4onFloor]

oh ya, your timing could be off too

[tealrabbit]

Yes it is a carb, not a TPI.

Is there any way I can find out if it is a vacuum leak?

Thank you for the fast reply by the way.

[ridge_runner]

put a vacume gauge on it or look for any disconnected air lines

[4onFloor]

ya do what ridge said, put a vacuum guage on it. you should have 14-22 inches of vacuum at idle, unless you've changed cam

[68chevelle]

does it only smoke at first and then stop? if it stops it kinda makes me think that the carb is leaking and fluding the engine while it is off and then takes a while to burn it off. what kind of car is it? a quadrajet? im betting it is. if so it probably needs to be rebuilt by someone who knows quardrajets, or get a new carb. if it is there are some plugs in the carb that need to have JB weld(the greatest stuff in the world) put on to stop them from leaking and letting un-meatered gas into the engine.

[burnM]

It could just be that the float is cracked from age. But, if you suspect a vacuum leak, use a spare piece of vacuum line, run your engine, stick one end of the hose to your ear, and the other to wherever you think there's a leak. You should hear a slight hissing sound through the hose when (if) you find a leak.

By the way, carb rebuild kits aren't really all that expensive - 40 or 50 bucks for a complete kit in my area..... my first rebuild was a q-jet, and it wasn't too hard. Ya don't know 'till ya try!

Good luck, keep us posted.

[68chevelle]

It could just be that the float is cracked from age. But, if you suspect a vacuum leak, use a spare piece of vacuum line, run your engine, stick one end of the hose to your ear, and the other to wherever you think there's a leak. You should hear a slight hissing sound through the hose when (if) you find a leak.

By the way, carb rebuild kits aren't really all that expensive - 40 or 50 bucks for a complete kit in my area..... my first rebuild was a q-jet, and it wasn't too hard. Ya don't know 'till ya try!

Good luck, keep us posted.

WTF are you talking about. first of all if the float was cracked,(asuming that it is a metal one and not a foam one like most), it would only flud causing it to run poorly, after it has been ran for a few seconds letting the float bowls fill up. and second do you know what vacume is? i hope you were joking about your vacume leak test. when something is on vacume it is sucking in air, thats what causes the hiss. so it hisses if it is not leaking/if there is vacume. and just cuz im curiouse, how would you hook up, to be able to listen to, a vacume line to see if the intake manifold gasket was leaking? how would you do it to see if your carb to intake gasket was leaking? you can't. the only thing that you said that is acurate, IMO, is about the quadrajets not being to hard to rebuild. as far as them being 40-50 bucks your getting riped. it bothers me when people say things that are in no way true and when they say something about something they dont know about. its like telling someone to light the gasoline in the gas tank to make the car move. its could cause some seriouse damange under the right conditions.

[tealrabbit]

Yes it onmly smokes right when I start it. In fact the longer I drive, the better it runs. And if I don't give it a lot of gas at first it will run really bad or even stop running, so the leaking carb sounds likely.

Is it a lot harder to rebuild a carb than to replace it? I can buy a carb for 270$ or so but 40-50$ is a lot more tempting. Problem is I'm a lousy mechanic.

[68chevelle]

it is probably easier for you to replace it than rebuilding it. but it is not hard to rebuild a carb. you just need to pay atention when you take it apart so you know what goes where when you put it back together.

[4onFloor]

68chevelle, i think what burnM was talking about with the hose was a stethescope idea, cant say i've ever done it that way, but i'm sure it'd work.

is your car hard to get started, as in do you have to pump it a lot to get it started? i'd make sure that the carb is ok first, but you may have a burnt or poorly seated valves.

[burnM]

Originally Posted by 68chevelle

WTF are you talking about. first of all if the float was cracked,(asuming that it is a metal one and not a foam one like most), it would only flud causing it to run poorly, after it has been ran for a few seconds letting the float bowls fill up. and second do you know what vacume is? i hope you were joking about your vacume leak test. when something is on vacume it is sucking in air, thats what causes the hiss. so it hisses if it is not leaking/if there is vacume. and just cuz im curiouse, how would you hook up, to be able to listen to, a vacume line to see if the intake manifold gasket was leaking? how would you do it to see if your carb to intake gasket was leaking? you can't. the only thing that you said that is acurate, IMO, is about the quadrajets not being to hard to rebuild. as far as them being 40-50 bucks your getting riped. it bothers me when people say things that are in no way true and when they say something about something they dont know about. its like telling someone to light the gasoline in the gas tank to make the car move. its could cause some seriouse damange under the right conditions.

Wtf I'm talking about, is using the vacuum line as a cheap alternative to a mechanics stethoscope (like 4onfloor said). You can use this method to hear things that you otherwise couldn't with the surrounding noise. Ever hear of using a broken broom stick handle to check for a bad bearing in an alternator? Same idea... cheap, and effective.

If the float is taking on fuel, it will sink to the bottom of the bowl, resulting in the carb constantly taking in more fuel than it can properly meter, resulting in flooding and the engine puffing out gobs of black smoke, and running like crap. He had stated that the car had been progressively getting worse and worse, and it seemed to match a symptom that I had with a previous car.

I may have read his post poorly... I did not however, bash someone else's input, and not offer anything constructive to help with his situation. If he was going to go out and buy another carb for his car, it may be worth it to take the existing carb apart and see if there is a problem that would otherwise be easily fixed.

I'm not the one who is "ripe". If I am getting "ripped" by paying 40-50 bucks, so be it. It is still cheaper than paying attention to a burn from you.

[68chevelle]

ok yeah, my bad. i read your post incorectly as far as the vacume line. so i apologize. i didnt mean to come off as a jerk either, but i see that i did now. but as for the float thing, it will not constently take in more fuel, it will take a few seconds, usualy atleast 15-30 seconds, before it begins to overflow out of the carb and cause it to run poorly. it take the few seconds because the carb will not stay totaly full. some fuel will disapate.