Rochestor Carb Fuel Fitting Issue

Discussion in '1947-1954' started by cmkruse, May 22, 2019.

  1. cmkruse

    cmkruse Member

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    I Have a 54 235 engine with a Rotttenchester B carb in my panel truck. I bought a replacement carb from O'reillys and it came with a larger fitting size in the air horn than the one I removed so my stock fuel line won't connect to the carb. I looked on line and can't find the correct size fitting to adapt the carb to the fuel line. I had an old brass fitting that fit the larger air horn bore and was able to determine that it is a straight and not pipe thread. I have two other carbs that have the same size fittings as my original carb but they are for 216 cu in and the bolt pattern for the mount is different size. Anyone heard of different size fuel fittings being used in Rochester B' carbs?
     
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  2. vwnate1

    vwnate1 Member

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    Pics would help here.....
     
  3. cmkruse

    cmkruse Member

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    Thanks Nate, I'm working on it:)
     
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  4. cmkruse

    cmkruse Member

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    IMG_1058[1].JPG
     
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  5. vwnate1

    vwnate1 Member

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    Looks like one was stripped and re tapped .

    I cannot imagine how this is any problem ~ just get the correct Weatherhead brass fitting and off you go....

    ? What's wrong with the old carby ? .

    They're pretty simple to overhaul .
     
  6. cmkruse

    cmkruse Member

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    The old carb was rebuilt at least three times and it never stopped leaking and on occasion the float would stick. I just got tired of taking it off and working on it so I bought a remanufactured from Oriellys and it's the one with the bigger fitting bore. I looked all over town - four parts stores and a hardware store and no luck finding a fitting that would work. As usual the counter kids didn't know the difference between NPT and UNF threads. I gave up and returned it and ordered a Carter per the listing on the store computer for my 54 235. When it arrived it was a universal carb arrangement with a sticker on it that said something like " This if a functional equivelent carburetor". Well it had enlongated mounting holes and extra vacuum port fittings/tubes and didn't look anything like the Carter depicted on their website. After a fit check I took it back and got my money refunded. So now I'm trying to find a good Carter YF per some of the recommendations on the various forums.
     
  7. vwnate1

    vwnate1 Member

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    Hoo boy .

    I feel your pain .

    The float valve sticking is likely a dirty fuel problem, do you have a clear plastic filter in there anywhere ? .

    I had endless flooding issues in my '46 3100 the Summer I bought it, (43 years ago) in time I learned to remove the fuel hose (the steel pipe had been cut my God knows who) using two nickles on the spring typ hose clamps, then I'd jamb an old #2 pencil in the open hose end, start the engine and run it until it died, then re connect everything, this way the float drops wide open and if you're lucky the initial rush of incoming fuel washes the tiny but of crud off the needle and you're good to go ~ such is how flooding was handled in the field or out on the road when these trucks were new .

    If the float isn't mis adjusted it's very easy to set the float height *perfectly* then screw it up as you re assemble the carby by barely grazing the float on the side of the bowl .

    Once you have the flooding issue fixed, often the carby still weeps because someone else long before you, tried to stop the wet air horn gasket by cranking down the four screws, this of course, warps the air horn to float bowl surface so no matter how perfectly you adjust everything, that damn gasket weeps and dribbles gasoline all over the hot manifolds....

    (? headache anyone ?) .

    This only good fix I ever discovered for that was to hand make a new air horn gasket (yes I know it has lots of angles and special small holes) and then glue it on both sides using Permatex #1H sealant, the nasty aircraft gets hard as a rock and you'll never get that thing apart again without a crowbar & sledge hammer stuff...... #eek# .

    Not much fun I know .

    I suppose you could glue two air horn gaskets together then glue them both to the carby....

    If you can find the correct c@rter YF carby and it's not worn out or ruined by ham fisting, you'll love it .

    I wish I could help you here but I'd need some old Rochester carby cores and a 235 engine that runs to make it right .
     
  8. cmkruse

    cmkruse Member

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    Ah YEs, the voice of expierence once again. I think I ran into all those issues that you mention. I also tried to level the air horn surface by sanding on a flat plate. I didn't think to try the double gaskets though. I looked at the weatherhead catalog on line and I couldn't find a UNF fitting as all the listings are for pipe thread. I believe who ever retapped the replacement Rochester used a straight thread tap. I don't know but now I guess all the fittings on the carb are original NPT. Doesn't matter now as I returned the Carb. Anyway thanks for the sympathy. I'm going to go with a YF if I can find one at a reasonable price.
     
  9. vwnate1

    vwnate1 Member

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    Well yeah, I've worked on these, once or twice you know #rolleyes# .

    Please keep us posted .
     
  10. 51 HHR

    51 HHR Member

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    Also if your use an inch pound torque wrench or driver on the air horn bolts/screws to make sure you’re not the one tightening them in evenly.
     
  11. cmkruse

    cmkruse Member

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    UPDATE- I obtained an carter YF 2100s which is the right one for the 54 engine and things are idleing great now. THANKS
     

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