Beemon

I don't think the carb you sent me had ever been in to. I found a cocoon inside the fuel inlet ports and the jet and accelerator pump were original as far as I could tell. The accelerator pump actually was broken and doesn't compress all the way and the carb must have had a fire because the primaries were deeply scored with soot. It works great now, it's just I didn't set the floats right so when I can adjust them and eliminate them as the problem, then I'll move on to the next problem. The carb was in really good shape otherwise, cleaned up extremely well but the surface was just tarnished on most of it so I painted it.

Apologies for not doing what I said I would do today. Between work and a perilous differential equations exam today, I didn't have time to exchange air horns. What I did do, however, was contact CarbKing and put together a plan of attack. Between studying, I was also doing some research on the side. Having a lower float level than the peep hole causes an atmospheric imbalance that inhibits the operation of the venturi and likewise having a higher float level causes the engine to dump too much gasoline. This pressure differential is balanced by the floats at that specific level for the purpose of proper venturi operation. So a lower float level creates an overly lean condition. As we were discussing via phone, compensating for this lean condition by adjusting the idle mixtures to be more rich causes puddling in the intake that bogs acceleration to the point of shut down. So, I can assume all floats are different despite their solder joint and will be bench testing the floats for proper fluid levels with the carb that is off and then swap floats between the two and continue bench testing. The key fluid level is the peep hole bottom threads, outlined in the shop manual as the correct float level, which is funny that their specification of 1 35/64" was too low in the bowl... also makes sense to have the primary floats sit higher due to the added volume in the bowl from the accelerator pump shaft... I must also admit right now that I have a pertronix ignition module. This question wasn't asked of me, but through my research I've obviously messed this up big time. No need to scold me, the speed shop that rebuilt my distributor almost one year ago talked me into the 'benefits' that I was naive about and didn't know any better. I'm picking up the points, condenser and coil tomorrow from NAPA. You guys must shake your head a lot at my threads. "Dumb kid, he'll learn eventually." In my defense, only two people in my family owned and maintained classics - my grandfather, whom cared for his Buick from 1956 to 1978 (when his son junked the Dynaflow) and is too old to help me or remember how to help me, and my father, whose eager to help and his earliest car was a high performance 1968 Dodge Charger with an alternator... if you get what I mean. Maybe my first carb was perfectly okay and it was the pertronix playing tricks on me? Who knows, we'll find out by the end of the week!

If that's the case, why would the shop manual specify setting the floats the same level? I'm assuming the floats are higher in the primary to accompany the added volume from the accelerator pump and power valve assembly? So if this is the case with the arms, then the float with the arm soldered higher would be for the secondaries since they would drop more? I'll be giving you a call later today when I purchase my second carb kit and a new bowl gasket.

Thanks for the write-up NTX, always appreciated! 600 RPM is high, the Neutral idle is supposed to be 450 RPM, but I was never able to get it that low and steady with the old carb. The only reason I noticed the fuel filter was because on the other carb, it would stay at least half full whenever I was looking at it. This one flows fuel but didn't fill after coming off fast idle. So this is another theory that I've come up with while I was at work. If the float is set too low and cuts off flow before it can fill fuel to the accelerator pump level, then the accelerator pump can't squirt fuel into the venturi and cause it to bog. Is this a correct assumption? I only now put it together based on what you said about the secondaries allowing too much air and killing the engine. If it was flooding, I feel like the secondaries opening would actually help it run better and not kill it. I also recall not smelling any fuel vapors. If it was flooding, I feel like gas would have poured out of the inspection holes as well, which was not the case. I'm going to run over now and pop the old top on the new carb and see what comes out of it.

Did you spend the money on those fancy roller rockers?

Also another good point. I'll pull the top tonight and swap tops and report back in the morning.

The fuel pump is working, it still pumps fuel into the filter. The filter just isn't holding fuel like it used to and the floats are different between the two carbs so I think there's a fuel metering error going on.

I'm a bit weary about adjusting the floats in the other carburetor because then I would have two floats that are the same. I'll put the ones I adjusted in the working carb and the others in the one in the car and see what I can learn. I'm thinking of maybe bench testing the floats by filling the bowl with gas and then adjusting the floats until the gas comes up to the threads on the inspection hole. Guess I should have done that in the first place...

Thats a good point. When I get off work tonight, I'll pull the air horn off the new carb and put the floats from the old carb in there and see if I can get it to run. You know if it ain't broke, don't fix it. Or so they keep telling me.

I took apart carb #2 (the one I had rebuilt by someone else) this morning and checked the float levels. The primary and secondary floats were two different sizes, to my surprise. The float on the front was about 1 1/8 to 1 1/16 for the full position and the drop was 1 3/4. The rear float had a 1 5/16 full position and a 2 inch drop. I also attached a picture of the shop manual that depicts the 1 35/64 inch max full position with the 2 1/4 inch drop. There must be some type of witchcraft going on here. Also the carb had a leather accelerator pump.

Yes I must have played with each one for a good while. I adjusted the "full" position first, squared them, checked their full position again, and then their "empty" hanging position, and then back to their full position. I had to really bend them out, though. It was a radical change compared to how they came, which leads me to believe either it was taken apart before, or at some point at the factory, the specs were changed. Or maybe I just dropped them really hard, but I don't remember doing that at any point. I even opened up the peep screw and rocked the carb back and forth to ensure they were moving up and down in the bowl. I wish I took the top of the carb off last night to see what was and wasn't wet but it was near 1 AM when I got off work last night.

By max I mean how high they float when the bowl is full. The choke is not the issue because its fully open and Jon 'Carb King' 's kit came with brand new primary jets, etc.The carb was operating as it should when it was on the fast idle cam.

I was going to post this in my other thread over in modified, but I figured this would get more hits. I also want to point out that this isn't my original carb, it works ok but has it's issues - this is the carb I received from Mr. Earl. I purchased a carb rebuild kit from Jon last week and had the carb cleaned, dipped and re-assembled by yours truly. I want to point out that this was my first carb I've ever worked on period. I grew up playing with LEGOs, so this was extremely fun for me. I kept all the different parts in separate plastic bowls per area, especially the different check balls, so not to get them confused. (Put the last of the linkage back together and checked to see it was 8:00 AM! ) The only piece of information I used the shop manual for was setting the floats. I think this is where my issue is. The car started perfectly, I set fast idle with no problem at all. Choke was set too rich, so I backed it off after it fully warmed up and set it so the choke was fully open. Got the idle down to ~600 after some linkage adjustments and started playing with the idle screws. I set each idle screw in all the way while the other was at factory level and the car did not die, so idle circuits are good (checked them with water before assembly anyways but wanted to test anyways). It was idling great, but the accelerator was bogging pretty bad and when both barrels went open the car died. When I was setting fast idle, the accelerator pump worked flawless, even better than it had before, so I know it has nothing to do with the accelerator pump and power piston. There's no vacuum leaks around the base or gaskets, checked with some spray and idle remained neutral. Even the starter switch, which was pulling vacuum on my other carb, wasn't pulling vacuum because the right check ball was in there and sealing up against the flange. I think it's the floats because when I was setting them, they were way out of factory spec. I had to bend them up to achieve max float level and then I had to bend the tang to achieve min float level. I had a feeling in the back of my head that this was wrong, but I kept moving forward (It was early in the AM, I was ecstatic I was on the last leg). I'd also like to point out that I love fuel filters where I can see what the fuel is doing. On startup and idle, the fuel filter filled with fuel like it always did and I don't recall when exactly it turned into a trickle of fuel going through the filter, but that was my first clue. When the engine went off the choke and was at warm temp, the fuel filter was almost empty and the accelerator bogged. My second clue was when I opened all four barrels during a bog, the engine died and I couldn't get it to start again. I immediately checked the float level screws and not even a slight trickle from the secondaries (both primary and secondary floats are supposed to be the same per the shop manual), that was my third clue. So my question is, what is the correct float level for a Rochester 4GC off a 1956 Buick? I'm figuring that because of the Ethanol gas, the floats don't float like they used to and the fuel is either more or less dense, causing the factory spec to be out of alignment with the carb. I haven't pulled the float cover yet to see what's wet and what isn't, but I'm going to assume either the floats aren't lifting high enough to allow fuel into the accelerator pump or the floats aren't rising high enough to shut off the fuel flow and it's flooding the engine. I'm pretty sure it's that second one because it didn't want to start after it died. Also I painted the carb bronze because the original plating was pitted and worn on a lot of the carb after it cleaned up... I figure when I'm rich and famous, I'll have it replated but for now at least it looks good and consistent. I also found the original choke stove pipe that was cut off the car way back whenever my Uncle dismantled the engine and left it for me to pick up - I crimped the end so it wouldn't cause a vacuum leak and just stuck it into the original hole haphazardly. Worked out pretty well, better than the electric choke ever did, but that's to be expected. I also attached a pic of the original carb (#1 (the one that has been rebuilt by two different people), not #2 I just rebuilt) because it has the original idle screws. Jon's kit is the only kit I know that uses a leather accelerator pump and includes brand new idle screws. Here are the pics:

Thanks for the tip! I purchased an HF sonic cleaner so I was going to try that out before dipping in anything. Read a lot of good things about sonic cleaning and the HF unit was $60 + a two year warranty. If it doesn't work out, then my mom has a decent jewelery cleaner for mothers day (jokes of course, it already broke... good thing it has a warranty...)

Thanks! The carb kit arrived today! I'm going to begin tear down of the second carb here shortly. I hear boiling in 4:1 water and lemon juice works pretty well, but I'm always skeptical about these home made concoctions being passed around on the internet. I'm also not really interested in dipping in a corrosive acid dip that can ruin internals/skin and give me lung problems, so any tips on cleaning out there? I won't be able to give Carb King a ring for another week, in hind sight I should have asked first. I was really bummed out that things were going so slow for the build at the moment, but it's really picked up some speed now. I get paid again this coming Friday, so I'll be putting in for another carb rebuild kit. I figure if I can get this carb rebuilt and on the car by Monday, and it's running great, then I'm hoping it runs better than what I have now. I've had this carb looked over by three different people in it's rebirth and it always seems to have a problem or vacuum leak. I swear the check ball in the ignition circuit is supposed to seal the vacuum from leaking out but it sucks air on mine all the time... these little things that have me wondering if it was put together correctly in the three times it was gone over.

Here's another update, got my prototype air cleaner back from the lab. Test fit it on the car, and it fit like a glove. A pretty proud moment for me. Seals up good. I also didn't go cheap like everyone else does on the market - the base is as thick as the carb air cleaner flange so the seal surface of the gasket will be there. It's also shorter than I expected. The two intake manifolds are about the same size and I'll have to end up using that half inch adapter plate, so I'll have plenty of room under the hood. I just need to make smaller cleaner mount studs now. Of course here are the pictures. I'm going to coat the parts with a resin "case hardener" and sand them before painting. The printer was good up to three decimal places, so they aren't perfectly smooth as evident from the first picture. The air cleaner cover I found was off of an old Harley. I got the idea while looking for interesting air cleaners, saw them, and they reminded me of old Mopar dual quads. I'm not one for flair under the hood, but I think they'll look good. After school tomorrow, I'm going to stop by Home Depot and look for some heim joints (their website lists them but that's not always the case). I've been thinking about where to hang the ignition coil, too. I'm not one for putting holes in the car, so I think I'm going to hang it from the ballast resistor mount. Since I went with the Pertronix, the ballast resistor is useless at this point anyways. I'm getting pretty excited now, the only hard thing I'm waiting on is the carb rebuild kit for the second carb. I think I might go with a 2" filter instead of the 3" so the cover doesn't have a bit of filter exposed below it, but I'll pass judgement after it's on the car.

Right now I run 235s from the junkyard to get the vehicle moving, they were a steal and I had them leak tested by firestone. They only rub when lock to lock and going over a curb simultaneously. As for your bumper, you can always cut the exhaust short and clamp tips that point down behind the bumper.

Just wanted to post an update. I got some distilled white vinegar late last night and some disposable plastic bowls and let all the parts sit. After 14 hours, the filter element wasn't bad, but the vinegar was a green color and heavily saturated. I dumped it out and it was some of the nastiest stuff I've ever seen. Put new vinegar in a new bowl and re-submerged the filter after wiping it down. The other bowls weren't as dirty but were oxidizing whatever the orange resin was on the inside of the pot metal or whatever these things are made from. The bubbles off the screw especially were just covered with some type of white paste looking thing as soon as I shook the bowl. Fuels must have been pretty nasty back then.

Yeah I'm curious as to where that even came from. My car came 100% complete (save throttle spring return bracket and dashpot bracket) and I've never seen anything like that. Also interesting the starter is green, mine came off black.

There isn't any type of part number, though when I was trying to find reference images, I came across both styles, the earlier one only having a drain plug. Thanks for all the tips, guys. Still a little hesitant to use it, but I think what I'll end up doing is putting a metal inline filter at the pick up tube and have this one at the carb so it looks period correct.

Thanks for the replies. I'll try the lacquer thinner and see if that helps. If they were junk, then I'll just drop it if it doesn't come clean. It just looked really interesting, both in form and function. Kind of reminded me of a catalytic converter.

Okay so before anyone grills me for not using the search bar, I did find a few threads about cleaning these old filters up. They mostly state carb cleaner. Cleaning is kind of an issue for me, however, and I want to make sure this filter is saveable. When I opened it up, there was some type of built up varnish that reminded me of bow string resin for a violin. As you can probably guess from the pictures, the varnish was as high as the "clean" part on the filter element. I've had the filter soak in PB blaster for a few days now and nothing has really changed. The two way fitting is still siezed and I can't get it loose. Both sides of the filter are rusted, but I don't think it's rust since its more of a pot metal and the exterior didn't rust at all for the years it's been sitting? Also the rubber gasket is pretty much gone. About the only thing I'm not too worried about is the tube in the center, I can get that cut locally... The filter also had thin, white strands of what I could only assume to be was nylon, which was also present in the fuel pump when I rebuilt that. Again, I've read threads on cleaning these, but would this apply? Fluid seems to seep through the filter element no issue, but it's just extremely nasty with no change after sitting in penetrating fluid. Also any tips on removing the other fitting? I don't want to put it in a vice and I don't want to put pressure on the other fitting in fear of stripping the threads. The only type of replacement stuff I could find are for glass bowl filters, has anyone had success re-using the rubber gasket? It just seems really brittle and hard to me. Also please excuse my helper...

I guess the band is there to guide the wiper down the edge of the windshield? It has a wide and slow option and then a short and fast option, so I assume the guides on the wiper blades are there to keep the wiper on the window as it wraps around during the wide and slow operation.

My dad always told me to take the blanket out so you don't get the picnic pitch all over the back seat. Haha Looking forward to seeing it complete, I want to see those custom hub caps!

I have to do my third oil change soon (1500 miles on the motor), but what I've done is jack the car slightly off the ground and loosen the bolt so it's hanging, then unscrew the bolt by hand while holding the jar. I'd gently lower the jar vertically and then tip it over slowly until the filter slides out into the pan. You have to have steady hands, my first time doing it I sloshed the jar and oil just went everywhere...