ok heres the deal, truck ran great for several years.. started having trouble with carb boiling over and leaking gas everywhere (rochestor b)... I rebuilt carb same problem.. then reading post i figure out rochestor b carbs have a body warping problem... so I bought a professinally rebuilt carb (rochestor b) at swap meet.. talked to the guy when i bought it, he assured me he had done many of this type carbs and had straightend the bodies etc... ok I though we are good to go, handed over the $ and walked off with the carby. put the carb on the truck this weekend..can't get the thing to run right.. rough idle(actually can't keep it running at idle) seams to run way to rich black smoke,, seems to load up... so I tune up the truck to be sure.. new plugs, new points, new condensor, new rotor, adjusted the valves, timed truck (best i can with very poor idle).. set dwell, replaced vacumm hose just to be sure no vacuum leak. checked heat riser it is functioning correctly. Still same problem.. can't get this thing to run right no matter how much i fuss with carb... seems to be running way to rich. Carb does seep gas at gasket seem... not to happy about that.. but I see the same seeping on the trucks at car shows also seems to common with the rochestor B. What now? only thing i can think of is pull new carb apart and lower float level... or what go for a third carb crazy... these things are so simple should be easy. any Ideas?
carb I have had this problem a couple of times. Both times, the float had a hole in it and filled (or filled a little) with gas. I either replaced the float or removed the gas and soldered the hole. One other time, I found that the threaded shaft (to fasten an aftermarket carb top to the carb), was screwed in too far and either held the butterfly open or closed (or somewhere in between). Had to readjust the shaft outward so it would not interfere with the flapper. Good luck. Penniwinkle
I Know ! Since it's both leaking at the joint _and_ blowing black smoke it s clearly running to rich ~ often as the air hod is assembled to the float bowl , the float touches the edge and is pressed up wards a tiny bit , this bends the float tab , causing to much fuel to enter the float bowl before the float valve can close . Fix : ever so carefully remove the air horn (top of carby) , take your tiniest flat blade screwdriver and bend the tab touching the float valve , open a bit , then re-assemble paying attention to not let the float touch , if it does , stop and do it again . I find it *much* easier to leave the carby bolted to the intake and simply disconnect the cables and four screws , lift the air horn up and away.... There's a brass power valve inside that's held into place by a spring , it must *easily* move up and down by gentle finger pressure , rotate it and if it's bent even a tiny bit , you need to take that part all apart and bend it back then ensure the BB in the bottom is the correct size , re-assemble and it'll be good to go . the brass plunger thing aften has longitudal gouges on it , use BRASSO or other brass polish to make it shine again so it's slipping up and down easily . I hope this helps ! I also hope you still have your old carby...
ok took the rebuilt carb appart to day, before I saw nates reply. The float had a leak as penniwinkle suggested, fluid inside.. so I swapped the float out from another carb.. ran better but still did not run well. opened the carb back up and lowered the float just a little, ran worse. opened it up a third time moved float back up to specs, and made sure the second was dry. again runs better but still not not well, rough idle. but at least it keeps running. so now that engine is hot I recheck valve adjust since valve cover is still off, recheck timing right on the bb at 500 rpm, dwell is at 34. spray starting fliud on intake top and bottom no leaks. points new, plugs new, rotor new condesor new, cap new. Now I am totally stuck.... so I go rummage around my shop and locate a carter w-1 carb that looks in good shape.. put it on the truck just to see.... starts right up and idles fine... the carter is not the stock carb, and has some throttle linkage problems.. but it proves the idle issue is the rochestor B carb. tomorrow I'll pull it apart again and see if I can determine what Nate is refuring to.. thanks all.. more to come. looks like a carter YF 964s might be a stock carb?, I will have to see if I can find one of those.
Carby Fun (or not) O.K. , you have a 216 , right ? the Carter W-1 is indeed the original carby , they're fine although I vastly prefer the YF Carters and so will you (said the man who only runs Rottenchester B's on his truck's 235) Look at the tip of the mixture needle , often some DPO has run it in too far/hard and bent the tip or dented it , or worse yet , screwed up the metering orfice in the carby . if the tip isn't perfect , find another , never try to fix them . TOMCO still makes brandy new brass floats for Rochester B's , available through NAPA stores and thier onLine catalog too , plus other important parts for it . Keep us posted , glad to see you've narrowed it down to the carby , might be time to drain and return it , ask for your $ back and start over with anopther core .
ok located another carb today.. rochestor b.. not rebuilt.. but it has the 235 base 2-15/16 " the uppper body looks the same.. I am thinking I may be able to swap the bases out with the 216 base 2-11/16? anybody done this before? Nate I don't think the carter W1 where stock on a 1953 3100 pu, 216 were they.. everthing i have indicates rochestor B or carter YF? trying to stick pretty much to stock on this rig, Yep can't take the rebuilt carb back, cash deal at swap meet. I will have to eat it. bummer
No Worries Just sawp the good B base to the new smaller 216 carby and give it a go . I forget what year they swapped from Carter W-1 to Rochester leaks alot Series 'V' but Carter YF was NEVER from GM... Take your time anf ind one , get it into decent shape and install it , you'll be amazed at the increase in power and easier starting , idle on and on.... Don't sweat it but do lesarn your lesson about swap meet junk ~ I buy lots of it but only at scrap value so if it's junk I can still break it for parts or properly fix it my ownself . besides , if you ask the sales guy " will this fit my old XX ? " , he'll ALWAYS say ' YES ! ' just go get rid of it.... Beware , we'll help you out right here , good guys all , they teach me lots . Don't forget : " Carby " is a Fench word that means : LEAVE IT ALONE !
