Jimvette; The vacuum hose is pulled from the dist. and timming set at 10* with an idle of 1100 rpm with idle screws backed out all the way. Dual return springs on both carburators helps a little but gives a very stiff pedal. Still, has a sticking throttle at 2000+ rpm and unsticks once the ignition is turned off.
My "barn find" '56 Cadillac is now running. After installing new gas tank, fuel pump, inline filter and flushing fuel line it started and ran multiple times for ± 30 minutes. Then engine started loading up, smoking and rear carb leaking fuel. Can I pull the top of the carb off while mounted and check the floats along with the needle and seat? I just want to do the minimum with the carbs for now and get back to the details later. Any suggestions on how to do this most easily?
The float assys, power piston assy and accelerator pump all come off with the top. There is a hidden screw under the metering rod cover. CAUTION this is not an easy carb to go through on the bench and much harder on the car. If you don't have considerable carb. experience it would be better to have them professionally gone through. Those are fairly rare carbs and would be worth the investment.
As far as I know , no one reproduces WCFB floats. If you need one you might try Gary Hodges Ramjet, in Salem Or. 503-588-3883. Be prepared though, the last time I had to outsource one it was$50 for a good used one. Hope this helps, Gary...
If floats are not available I hope that means that the demand is not their for anyone to reproduce them. Then that means mine should be ok. (-: If I need a rebuild kit where would I go for that?
It is unlikely that your floats are bad, most likely a stuck needle valve. If you have had success in restoring other carburetors you should be able to handle these. You can find a manual on line if you look around. Pay attention to what you are doing and be careful not to bend the metering rods. I found a kit at NAPA for my WCFB’s from a 55 caddy, part number 2-5039A. These kits are for a range of carburetors and most likely good for yours. Good luck
WCFB's had two patterns . The square pattern used on the early ones and a more rectangular one used on the later ones like the 55 and up Chevies. The AFB's have a bigger pattern yet but are easily drilled to fit the early manifolds using the rectangular pattern. It has been a while, but I think only two holes would be drilled to fit. I hope this is right.
Andy is correct for the later wcfb's and the afb's. The wcfb I am referring to is the small base carb. like for a 53 Olds. To answer you question Drill the Carb. I had a afb running on my 59 corvette for many years until I put the correct wcfb on. I think I had to put a plate on to except the wider secondaries on the afb (c) series.
I had a 53 Cad small base carb. It did not have the secondary flapper. It was terrible as it was hard not to bog it at slow speed. Your Olds may do the same.
Yes they have mechanical secondaries . I have this carb. on a 53 ford flathead intake and it is a pain to setup the secondaries .
ive got 2 stock 55 pontiac 287 wcfb on my 57 pont 347 punched to 354,10-1 compression, and a thumper cam.allin my29 ford roadster with a 3 speed manual and 411 gear.runs well all around.wondering what the cfm would be
I real do not know but I would guess about 450 cfm. I am pretty sure the ventorys are 15/16 "The carbman would know for sure .
is that 450 together or each? just wondering.and also what would be a good guess for cfm(carb size) for this setup.thanks
Hi Jon, you got us through the metering rod/vacuum spring troubleshooting, any additional tips that you can share? Any areas that can be improved? I don't have any specific questions, just looking for more words of wisdom from someone who has been through a few of these. I do have a nice 'Vette 2x4 manifold and four similar WCFB carbs (Chev throttle arms) to work with to hopefully make a working set-up. I have both a 283 and 327 core motors - don't know which will get built yet, but the carb set-up is for that project. Street engine, mild solid cam, 2600-2800 lb car, 4 spd.
New throttle shafts are available if needed. WCFB'S are not hard on throttle shafts so replacing is not usually necessary. The correct jets and metering rods for the dual 4bbl application are reproduced, RamJet in Salem Or. has them.
I just picked up a dual quad setup from a 1957 corvette I'm going to be scouring for parts to rebuild this setup . Great thread so far.
If the carbs are complete you shouldn't need anything more than a rebuild kit. Make sure you get kits with the leather pump. They are not affected by the alcohol in the gasoline. I run 2 58 348 carbs on my racecar. They sat for 15 years and in July I opened them up and nothing was screwed up and they worked fine when I took the car to the York Muscle Car Reunion, and made 3 passes at Beaver Springs after the show. I just spread the leather a little before I reinstalled the top covers. Same with a pair of carbs my buddy brought over. They are on his car now and he loves the way they perform on his '61 Corvette.
These 2 have matching numbers. I courious as to why WCFB's were built with both aluminum and cast iron bases. These are aluminum painted black. Then I ran a single 1953 Cadillac ( iron base) on the stock y-block intake it was necessary to restrict the exhaust gas fron under the carb and run an insulator. I assume this was because the original Holley 4000 had the fuel bowl high up and the WCFB's were near the manifold. The fuel did boil. These both have 3/8" insulators.
I need some advice here guys, I have a WCFB on my 53 Olds, its been rebuilt by the PO but when I got the car it was flooding so I opted to do my own rebuild, I got a kit from www.carburetor-parts.com I replaced everything even the check ball and retainer which hadn't been replaced in the previous rebuild. The issue I am having involves two springs, both are missing from the carb and both are not included in the rebuild kit, but both these springs are listed in the exploded diagram supplied with the kit and also listed in the shop manual....they are the pump return spring and the vacuum piston spring. I spoke with the guy at Mikes Carbs and although knowledgeable he was a little vague, he said if it was running without them then it should be OK. I need to know one way or another, should they be in there or not? in the bag of bits that came with the car was the old parts from the previous rebuild plus one spring which is the missing pump spring...did the PO forget to put it in? or was he told not bother as it wasn't needed? and just to confuse me even more the third pic below taken from the shop manual shows the pump without the return spring underneath it (see pictures)
I'm assuming the vacuum piston spring you're referring to is the one located under the power piston. It needs to be there to work against manifold vacuum for the power enrichment circuit to work properly. Without it the engine will go lean under heavy throttle and high load driving conditions. The power piston won't be able to raise the metering rods in the jets to richen the mixture when needed. There may or may not need to be a spring needed UNDER the accelerator pump, depending on the pump's linkage. If the linkage is such that it positively pulls the pump plunger back up in the pump bore when the throttle is closed it may me OK without the spring. Some linkage setups may require the spring to push the plunger back up in the bore to allow it refill with fuel for the next time the throttle is depressed. A specific shop manual for the car will probably tell you if it requires the pump return spring or not.
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