Guest tony78_280z Posted March 29, 2005 Share Posted March 29, 2005 there are no Haynes/Chilton manuals for hybrid Z's...No, but you get one for the motor, one for the car, and one for each special component in the car. And you then have a first source of info to turn to. Quote Link to comment Share on other sites More sharing options...
awd92gsx Posted March 29, 2005 Share Posted March 29, 2005 Believe it or not, but, I've found that http://www.autozone.com is actually quite an invaluable resource. I found all of the vaccum wiring diagrams for my engine ('77 El Camino 350) there along with quite a bit of other "book" only info. Quote Link to comment Share on other sites More sharing options...
Guest tony78_280z Posted March 29, 2005 Share Posted March 29, 2005 ...Cool, now download all that info and back itup on CD...... Quote Link to comment Share on other sites More sharing options...
Pop N Wood Posted March 29, 2005 Share Posted March 29, 2005 Man don't start out so complicated. Chances are your float is stuck or you have some dirt on the needle valve. The fuel is coming out of the overflow tube because the needle valve is not shutting it off. Try a little "mechanical agitation" to knock the dirt loose. Worse case pull the top of the carb, clean out the bowl and inspect the needle valve/float assembly for damage. Make sure everything moves without restriction. Fuel pressure regulator....sheesh. Quote Link to comment Share on other sites More sharing options...
Guest indy Posted March 30, 2005 Share Posted March 30, 2005 2 pages of posts, and no one has told him how to work a carb's choke. It is afterall, his first carb'd car. Since the delivery guy started and ran it with no problem, there's probably a good chance that this is more user error than real problem with the carb. Pumping the gas repeatedly will just keep flooding it, and you'll get no-where. If you just push a little, it probably won't set the choke. Quick and easy fix for a flooded carb, pop the hood and fully open the choke. Slowly open the throttle by hand to prevent the accelerator pump from shooting more in, and blow hard into the throttle bodies. You'll get a bunch of gas vapor shooting right back out and should clear the intake, tastes yummy. Hop into the car, again slowly push the throttle to the floor and hold it, crank a few seconds, should clear the chambers. Reset choke and start over again. When you get in the car push the throttle slowly to the floor once. This should reset the choke to its cold position (closed as you found when it actually started) and squirt a little gas. Then turn it over. If needed, use light throttle as it cranks. Did the car come from a cold climate? I've seen several cars in cold weather that would completely close the choke on startup, not letting any air in what-so-ever. Interstingly enough, the cars will run for 2-3 minutes before closing completely. The common lazy approach is to block the choke open slightly instead of correctly setting it. The choke *should* open over time, but depending on engine heat, outside weather... it can take quite a while, well over 5 minutes. It would probably be a good idea regardless to have the carb rebuilt and tuned by a mechanic. Even when carbs are running right, there's usually plenty of room to make them run better. HTh Quote Link to comment Share on other sites More sharing options...
Guest indy Posted March 30, 2005 Share Posted March 30, 2005 Double post. Quote Link to comment Share on other sites More sharing options...
Corzette Posted March 30, 2005 Share Posted March 30, 2005 I got a better idea...save up and get a holley and be done with it. Id say a 750 Vac sec for street or a 750DP for all out power etc....You mount the carb turn the airbleeds out 3/4 to 1 full turn each and ur in business. The 3310 model is affordable and a good carb as well as the 4779C DP. CorZette Quote Link to comment Share on other sites More sharing options...
Guest tony78_280z Posted March 30, 2005 Share Posted March 30, 2005 Man don't start out so complicated. Chances are your float is stuck or you have some dirt on the needle valve. The fuel is coming out of the overflow tube because the needle valve is not shutting it off. Try a little "mechanical agitation" to knock the dirt loose. Worse case pull the top of the carb' date=' clean out the bowl and inspect the needle valve/float assembly for damage. Make sure everything moves without restriction. Fuel pressure regulator....sheesh.[/quote'] Don't gimme no sh!t. I tried everything before I found my carb's problem. The dummy electric fuel pump didn't stop pushing and would flood the bowls and gas would pour out of every place! (Didn't jet spray out though) The pump said plainly on the box the PSI it was rated, but it didn't have a built in regulator or shut off. I put a pressure regulator on there and it quit doing it. True it could be a stuck float. Although, I would definatly advise checking fuel pressure before dismatling a carb. Easy check to avoid alot of possibly unnecessary work. Another situation with electric fuel pumps, I had a battery going bad. Somedays it held more charge than others. It seemed like every other day I had to retune my carb because the damn things fuel pressure fluctuated. This is why I got a mechanical pump now. Quote Link to comment Share on other sites More sharing options...
awd92gsx Posted March 30, 2005 Share Posted March 30, 2005 I plan on installing a fuel pressure guage anyway. They're cheap and might tell me if I am running too much fuel. I finally got the exhaust on and drove it. I havent' really mashed it, but, it didn't give me the "oh my Gawd!!" type of accelleration I was hoping for...but, I've only been driving around on the primaries and haven't really opened it up. Something is definitely up with the carb, though. Even though it was just rebuilt it doesn't idle quite right...seems to have kind of a rough idle. Hell...maybe it has a hot cam in it and I just don't know it. (I doubt it). I used my old muffler...but, I'm thinking it's not quite loud enough...so I'll replace it in the future. Quote Link to comment Share on other sites More sharing options...
awd92gsx Posted March 30, 2005 Share Posted March 30, 2005 Oh man... I think I figured out why my carb is spitting fuel back out... The number 3 cylinder isn't firing...I'm afraid it might have a burnt (or at least non sealing) intake valve. Quote Link to comment Share on other sites More sharing options...
Pop N Wood Posted March 30, 2005 Share Posted March 30, 2005 Doubtful a stuck intake valve will make a carb overflow. Quote Link to comment Share on other sites More sharing options...
awd92gsx Posted March 30, 2005 Share Posted March 30, 2005 No, it wouldn't cause it to overflow...but, it would cause fuel to spit out of the top of the carburetor when compression fired back through the intake. The head is almost off, so, I'll find out in a few minutes. Quote Link to comment Share on other sites More sharing options...
awd92gsx Posted April 1, 2005 Share Posted April 1, 2005 OK.... Well, it turns out I was wrong. The valves were sealing just fine. I pulled the head off, took it to a machine shop and had them check it out. The cylinder head was ok. However...the machine shop said it looks like #5 and #7 cylinders were crossing over compression by the headgasket...so...I took a chance and put it back together when a new headgasket. Just got finished. Doing the cylinder head wasn't too hard at all...what caused me grief, though, was getting the distributor right. I marked it, but, for some reason that mark didn't seem to matter...maybe I moved it and didn't remember it. Oh well... The GOOD NEWS, though, is that #5 cylinder seems to be working now (it drops RPM if I pull the #5 plug) AND I no longer spit fuel back out of the carb. Whether or not everything else is fine is still to be seen. I havent' really run it yet. Quote Link to comment Share on other sites More sharing options...
TheNeedForZ Posted April 1, 2005 Author Share Posted April 1, 2005 awd92gsx, I am assuming that you don't already know these : You might want to check the power piston system. If the manifold backpressure was enough to squirt fuel/air back out, there's a chance that the power piston can be popped out and remain stuck. Then what you get is a constant enrichment because the primary metering needles are raised at all time. Also, to really tune the idle mixture, not only do you need to tune the idle mixture screw, you also need to tune the throttle stop screw. Throttle stop screw adjusts the throttle blade position on the transition slot. opening the throttle a bit enrich the mixture(less air pass thru the slot), this also speeds up idle a bit; Closing the throttle a bit leans the mixture(more air to pass thru the slot), this slow down the idle a bit. An old carb usually have worn butterfly shaft bores that create vacuum leak : air enters the manifold thru the bore gaps. This is a main cause of rough idle. When you have a worn butterfly shaft bore, you either have to find a tighter throttle body or have a specialty shop install bushings on the old throttle body. Where exactly of the carb was the fuel shooting from when you had the problem? Hope this helps, keep us posted Quote Link to comment Share on other sites More sharing options...
Pop N Wood Posted April 1, 2005 Share Posted April 1, 2005 This thread is so aggrevating. Quote Link to comment Share on other sites More sharing options...
awd92gsx Posted April 1, 2005 Share Posted April 1, 2005 Unfortunately I can't tell *exactly* where it's coming from. Maybe I can get my wife to crank it while I watch it. I think the starter I bought is defective, though. About 2/3 times of trying to start it just cranks a couple of revolutions and then starts to whir (gm gear reduction type specified per JTR manual...unfortunately I bought it online so, I'll have to see what their return policy is.) Quote Link to comment Share on other sites More sharing options...
COZY Z COLE Posted April 1, 2005 Share Posted April 1, 2005 I must say the latest threads on carburetor's in this forum have made for some amazing reading......... LARRY Quote Link to comment Share on other sites More sharing options...
awd92gsx Posted April 2, 2005 Share Posted April 2, 2005 Still spitting out fuel a little bit from the carb. I did try something, though. I disconnected the power from the starter solenoid wire for the fuel pump system...and it still seemed to spit it out. So...maybe it i s the bowl levels...I dunno. I really know very little about carburetors, other than their theoretical operation. Right now I have a bigger issue, though...my starter has gone out on me (reman unit - maybe it died from me trying to start it so much - I dunno). So, I'll get to replace that this weekend. I've only gotten to drive the car about 4 times around the block - seems like I keep running into these little issues. Quote Link to comment Share on other sites More sharing options...
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