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Discussion Starter #1
Last fall when I parked my elky I had just rebuilt the carb and it solved my overfueling black smoke issue but caused a new one... it doesn't want to start when it's hot. I have an Edelbrock 4bbl carb and when I took it apart to rebuild it there were 2 L shaped rods (about 3" long) that come down from the top of the carb and point into some holes in the bottom of the inside of the carb. Whoever had previously worked on it failed to get one of them into it's hole and tightened down the screws secuting the upper half of the card forving a 90 degree bend in the tapered tip of that rod. So I went to autozone and ordered another one, it came the next day but was a little bigger diameter tip than the old one... I put it in anyways, finished it up, put it on, got some help adjusting it and it runs good. So... any ideas on the had start? It's like it won't turn over hardly but if I sit there awhile sudenly it starts right up. I think it might not be carb related. I also have some "excel" ignition system that was on it when I got it... think it might be the timing or something? But if so, why would it start doing this only after repairing the overfueling issue? (before the fix the high speed barrels were always trickling fuel and the car would spew black smoke). It's coming time in the next few months to get the car back out after the winter goes away so trying to think ahead here.
 

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It sounds to me like your describing one of the metering rods on a Q-Jet, do you have a Quadra Jet Carb? If so and the little rod was attached to the rear venturies (butterflies)(comes up when the back two barrels are opened) those are suppose to be the same size left and right. Otherwise that is one problem that is still there.

The rods go into the rear "Jets" This are where the fuel comes from when you are at WOT (Wide Open Throttle) They are inside the jets, sort of preventing fuel from leaking out into the intake when you not using them. Its actually a little more complicated than that but basically that is what they do.

I would re-build the whole carb not just stop at the one metering rod. The jets are replaceable or re-drillable depending on your level of knowledge, newbie's should stick with replacing them (when necessary). The Q-Jet is one of the best overall fuel efficient carbs on the market and with the right knowledge it can be a really good performer. If that is what you have Carter Carbs also has metering rods etc...

If your problem only started when you replace the rod then I'd re-check what it was that you did to make sure you didn't get anything in wrong. Also if you do decide to rebuild the carb do not brake loose the tiny little screws that hold the butterflies to the rod. They are "Staked: to prevent them from coming loose. If one does it will go directly into the combustion chamber and cause damage to your engine. I'd get a "How To" on Carbs if you are unfamiliar.

The starter could be bad and as it cools it works that is not an uncommon problem with Chevys especially if you have headers. A heat shield on the starter is an absolute must with or with out headers. Also if you have an oil leak on that side (Passenger) it can build up on the starter which will soak it and then the oil gets hot and cakes causing a similar problem.

If the timing is too far advanced it will act about the same. So there are several things that could be a problem although my guess is just one of them you have to figure out which.

Finally on the q-jets the primary fuel bowels where the jets horns are under the carb crack. This is not uncommon and in fact is very common. That will cause your Carb to "Run out of gas" over night. It actually leaks out into the intake manifold slowly. GM and most all reputable books tell you to use an epoxy to seal up the bottom housing. It is dead center of the carb underside. You'll see what looks like two "Pipes" or the housing. Encapsulate that completely with epoxy and let dry. Clean the area really good before you do that.. That fixes that problem for ever.
 

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Discussion Starter #3
I am confident that the entire rebuild was done correctly with the exception of that wrong sized metering rod. I used a rebuild kit from edelbrock and was under the supervision of an experienced mechanic when I did it. I think you might be right on the money with the starter and or starter/heat issue. Are these starters supposed to have heat shields or are they something I need to build, or buy?

I'm thinking about just getting a brand new carb because I don't want to spend forever screwing with it. I have an 85 with a 350 motor that has an Edelbrock intake on it. What carb should I get that will bold directly on in place of the old one? Should I stick with edelbrock?

I think I can go to the local auto parts store and buy a brand new varb just like the one I have for $189 or something. Plus, I don't know how much starters are but it might be worth it to change it so I know the history on it since I plan on having this car for awhile.
 

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Determine if you have a "Spread Bore" or a Square Bore Carb. If the intake is for a Spread Bore (Rear Holes are larger than the front ones) that is a spread bore. You can get an adapter plate to go to a Square bore (all holes the same size). Then if it were me... I'd get a Holley say 650 CFM. Those are really good and easier to work on.

The Edelbrock Carbs (Carter) are good also I have two but I'd rather have two holleys.

I forgot yes.... The heat shield generally comes with the starters but if you don't have on you can get one at an auto parts store.
 

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Yes, it's possible you need a starter heat shield, but it is more likely a poor ground somewhere in the starting circuit. The hotter the starter and engine, the greater the electrical resistance. A poor ground can work perfectly well when everything is cold but balk when the temp is up.

Clean both ends of both battery cables and the surfaces they contact. If the negative battery cable attaches to the alternator mounting arm, disconnect it and use a jumper cable attached to the engine instead. If this solves the problem, reattach the cable to the engine. The starter housing must have excellent contact with the engine because the starter housing and engine is the negative side of the electrical circuit. Also, you could have a "dragging" starter. The bronze bushings in the ends of the starter wear down over time. When the starter gets hot, everything expands and the armature (part that spins) touches the winding shoes (part that does not spin) causing the starter to really struggle (drags). If you know how, the bushings can be replaced for a couple of bucks and some labor or you could replace the starter instead.

These are just some of the possibilities. Good luck.
 

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I'm with spoonplugger here--if the engine is not (or barely) turning over it's likely to be an electrical gremlin in the starter circuit.

Did you remove or disconnect the battery during the carb work just for fire insurance??
Or it could just be coincidence.
Either way start with the easy and high probability battery terminal cleaning and work your way down to the starter.
 

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Electrical bugs can be very elusive. Had one that was in a coil wire. Started great when cold, but balked badly when warm. There was a break in the wire inside the plastic covering. Good way to find the culprit is resistance test with ohmeter. :)
 

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If you go with a Holley carb install a backfire preventer prior to intallation. It might save a few bucks if it does backfire. I had one on my 283 when I bought it. This time around I bought the Edelbrock. Holley's are easier to work on. Wished I had kept the Holley as a backup carb.
 

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Carb Preference

I've used Carters, Edelbrocks, Q-Jets and Holleys. Any carb can be made to do a resonable job if correctly tuned but I think that the Holley is the most versatile and easily tuneable. In every instance where I have been involved with a Holley that wouldn't run right some ham-fisted "mechanic" had done something really stupid. For a street driven performance car a properly sized vacumn secondary Holley will bolt on and run great.
 
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