put fuel to the tri power set up and I have fuel leaking out of the throttle shafts on the outer two carbs. What is causing this? How do I fix it? The carbs are rochester 2gs. Thanks,Mel
If they're assembled right and they're both doing it, the only thing that comes mind would be float level. A place to start, anyway.
We lowered the floats and they are still doing it. Where should we set the floats? Dont know alot about these carbs and bought a intake set up complete ready to run but as of right now not so promising. the end carbs have a regular base with the adj screw holes removed and the holes filled, Is this alright? I read that the outer carbs should have thicker butterflies to seal better and the bases for them dont have the screw holes. The center carb just has a vacum port off of the base but the end carbs have a vacum port on the front side on the top a real eye sore beings there blocked off with a cap ,Thanks,Mel
Sounds like they are flooding, probably dumping gas in your oil, too. Replace the needle & seat? Carb kits should be easy to find, come with a float gauge & specs. If they are small base, probably a 60 Chev or so would be the kit to ask for.
These things have been freshened up recently with the above mentioned carb kits, right? If not, it's probably to much to hope the little triangular shaped ID tags with the carb numbers are still attached under a bowl cover screw (carb top) inabling you to get the specific kits (not generic) for these carbs. OK, pull the top off the carb and look in the bottom of the fuel bowl. Centered between the main jets on the floor you should find a power valve (NOT the spring loaded actuating rod for it, even the TriPower carbs can come with the rod and they don't use power valves). If the power valve is gone, check the well it would screw into to see if it's passages have been plugged off. My next best guess would be it isn't and somehow is siphoning fuel into the venturi. You did make sure the float level was below the seam with the carb top, and not dumping fuel into a vent of some kind. These carbs are about as simple as it gets, best bet is to find yourself a factory mid fifties or so GM something service manual (which usually cover these carbs in great detail), turn to the 2 bbl carb section and study it. I think all the GM car lines used these things in one application or another. Just make sure it's the 2G Rochester type. A "C" suffix in the nomenclature (as in 2GC) refers to a carb mounted choke mechanism (connected to the manifold with a tube). If there is a manifold mounted choke stove connected to the carb with a rod it's a 2GV (common on 60's apps). If there's no choke mechanism at all, no provision for a choke blade (mounting bosses or holes on the air horn to mount one) or threaded mounting bosses on the body or the base to mount a choke housing or linkage, you've found a TriPower carb (obviously not true in this case with the cobbled up bases). I've never had trouble with modifying regular carbs, but I've always made sure I modified the bases to completely seal off idle circuits, vacuum bleeds, and transfer slots and checked the register of the throttle blades to make sure they seat well. As long as you use the factory throttle linkage as your model when making it up, I can't see you having a problem with vacuum leaks if you follow the above mentioned steps. I see nothing to be gained by eliminating the power valves from a carb so equipped. Just remember to also retain something close to the factory jetting for that carb. TriPower carbs used somewhat larger jetting to compensate for their lack of power valves. I think the setup on my 65 2+2 convertible came with 61's in it's center carb (the primary, which I changed to 57's to increase my fuel economy) which uses one of course and used 64's or 66's in the end carbs (secondaries) to compensate for the lack of one. If your carb bowl cover has what appears to be a little overturned thimble on it with it's lower edge spaced slightly off the carb, don't be alarmed, it's just a bowl vent and quite commonly found on some of these carbs. If all this sounds like so much Greek to you, try to find an old head locally who likes to tinker with this stuff and I'm sure they can get you squared away in short order. I'm pretty good diagnosing my Daughter's car over the phone from over 1100 miles away, but trying to get my brain to think well enough to be understood writing this stuff is a different kettle of fish, anyway I hoped I helped a little.
Just an added word of warning. You can get so hung up on the carbs and forget what can happen to the engine. I fought a flooding carb (1 carb) that was caused by dirt from the gas tank. By the time I got the carb problem sorted out I had ruined the brand new$$$ engine. If fuel is coming out the throttle shafts, then it's pouring down into the intake and into the crank case diluting the oil. Keep that oil changed while you sort out your problem. I added another fuel filter thinking my troubles were over. I never thought about the oil. It had just been changed. About a month later I had to rebuild my new engine. I was not pleased.
You didn't mention if all 3 were leaking. You didn't mention if you were using stock or electric pump. You didn't mention if you added a pressure regulater in line. If you are using an electric pump that is pumping 6+ lbs you may be blowing fuel light by the needle a seats. How about the vents are they seeping fuel also? Most times simple fuel pressure is overlooked and can cause the issues you are having. That's a start. 3-4 lbs max.
As said in the first post it is just the outer two. stock man fuel pump No p/r. Like I said I no nothing about these carbs so what do I look for to see if the vents are seeping fuel? Thanks,Mel
Ok Mel, here is another assumption on my part, since you are running a stock fuel pump you must either be running the carbs or cranking it over enough to pump fuel to the bowls. If so, after you do this stop and look down in the carb air horn. The first thing you will see is a piece that looks like a y with b no leg. That's a fuel discharge cluster. Do you see any fuel dripping or seeping from any part of it...top.middle or bottom?
The 2G has no choke. Usually doesn't have pwer valve or idle cicuits. 2GC has a choke, power valve and idle circuits. jerry
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