I've been trying to read through all the posts regarding 235 carbs but my 73 year old eyes are getting tired. Guess I'm not as good on the old interweb as I though. I'm trying to order a rebuild kit for the Rochester that is on the 235 that's in my '40 truck. Anyone out there able to tell me how to id the type? I've posted photos of the side and what I'm guessing is a serial number. If anyone can help I'd appreciate it.
Without a tag, there's no way to identify the application of individual Rochester B's. Is the engine in your 40 an original, or has it been replaced with a more modern one? The OEM carburetor on that truck would most likely be a Carter, since I believe all the Rochester 1 barrel carbs were post WW II production. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
Hi Jerry. The 216 has been replaced with a 1953 235. I've been doing some searching and from what I've seen on Mike's Carburetor website this is a B since it has a manual choke. Looks like the BV and BC had automatic or vacuum chokes. The rebuild kits I'm seeing will work on all 3 models.
A 1940 truck with original engine would have come with a Carter carburetor.
Rochester produced their first carburetor in 1949 (a two-barrel).
Later Chevrolet 235 engines would have come with a Rochester type B (yours is a type B).
The cast (raised) number you have pictured is an internal Rochester number for a "blank" bowl, prior to the bowl being machined. The bowl could be machined a number of different ways, and used on a number of different carburetors.
A very few (my guess would be maybe 1 in 20) Rochester B carbs do have the identification number stamped in the throttle body (Gord&Fran post above). Generally the number on the throttle body is also for a casting blank. Only way to know is to find the number and look it up.
There are some basic generic (gaskets and fuel valve) kits that may fit many of the Rochester B carbs. Purchase of the better kits is going to require the tag number.
Jon.
Good carburetion is fuelish hot air The most expensive carburetor is the wrong one you attempt to modify. If you truly believe "one size fits all," try walking a mile in your spouse's shoes! The Carburetor Shop
There is a number stamped into the mounting flange. It appears to be the same number that is on the bottom of the bowl (see photos, a little difficult to read in the photos but it's the same number). At this point I'm buying a general rebuild kit for Rochester B, BC and BV models. It seems to have all the parts needed and without the tag number I think that's all I can do. So now everything is cleaned and I'm just waiting for the parts to show up tomorrow morning, so they say.
That number is a cast part number. I guess I should have been more specific. I should have said the carb number may be stamped into the machined surface of the mounting flange.
Nothing on mine Gord. As I've said it must be an early "B" model since it has a manual choke. Speaking of which, when I got it there was this wire around the 2 sections of the choke control lever. The one part is attached to the shaft via a machine screw, the other part is the part that's moved by the choke cable. I'm not sure why this would have been done. I've attached a photo, blurry but you can still see the wire. I'm thinking the part that is attached to the shaft should be allowed to move within the confines of the part so the choke can adjust itself. Any thoughts on this?
Us old folks are stubborn. We'd rather spend time than money, lol. Besides, it was working fine until the engine just stopped spinning, which wasn't fuel related. Anyway, I'm going to keep plugging away.
I've reassembled it to see what could be missing from the linkage. I've also been looking at lots of photos of Rochester single barrel carbs. I haven't come across a photo exactly like this one. But when I put it together, including the bracket that holds the manual choke and throttle cables it appears that there should be a spring between the throttle linkage and the choke linkage. If you look at the throttle linkage there's a hole in the fixed part of the linkage (if I could figure out how to put arrows in pictures I'd do that but . . . ) If you go straight up from that hold there's a lip on the choke linkage. (In the larger photo of the choke linkage it's just above the last "R" in Rochester. A return spring there would pull the choke open unless the manual cable pulled it closed. The other part of the choke linkage, the part right under the screw, seems to allow the butterfly to move slightly when the choke isn't fully closed or open.
If anyone out there has one of these carbs could you confirm that the spring is missing or any other parts that you might think should be there.
Well after a few adjustments to the floats we're back up and running. I'm still going to see if I can find a return spring for the choke linkage. All the photos I've found are of the types with a solid bar linking the throttle linkage to the choke linkage, but in those the choke linkage has a hole in it where the rod goes. Mine does not have any where to do that. We'll see how this goes.
You've got a "mixmaster" there- - - - -the throttle body and fast idle cam is from a different carburetor than the main body and top cover. Also, the fast idle cam is on upside down. When the choke cable is pulled, there should be a piece of linkage that lifts the fast idle cam to a higher step. The only thing worse than a Rochester with all the correct bits and pieces is one that's been cobbled together from several carbs from the scrap bin. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
Thank you. I've been trying to figure this our for a while now. So, if I'm understanding what you're saying, the upper part of the carb, including the choke linkage, is from one Type B, and the bottom is from another. That would explain the missing link. I've been searching for a decent photo of a B with the same type of choke linkage as on mine, with the manual cable attached, but so far no luck. I just found the one I attached which, I believe, has the piece of linkage that you are referring to. However, mine does not have the choke linkage with the hole for the upper end of that linkage to go into. So if I turn the idle cam around, so that when the choke is engaged it will pull the idle cam up and thereby cause the throttle to open up more, and in some way link the choke linkage to the properly mounted fast idle cam, I should be ok?
The pic you just attached has the correct fast idle setup. The other one seems to be missing some parts, or it's a mismatch of pieces from different carbs. The cable bracket in your first pic appears to be installed incorrectly, also. The throttle cable needs to point downward toward the foot throttle area, and it needs to go through the cotter pin hole in the linkage to pull the throttle open when the knob is pulled. It's a sliding fit, with a small brass lock device clamped to the cable Jerry .
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
I've attached a couple closer photos of the carb on the truck. I think the bracket is on the right way and the throttle cable does point downward. I can see a small hole in the foot throttle control rod in the second photo. Is that the hole you are referring to for the cable from the throttle control knob? One of these days I'm going to figure out how to put those little arrows on photos.
The major difference I'm seeing between the 2 linkage systems is that the one on my truck does not have a hole into which the rod that is in the throttle control linkage can be put. In the photo I attached in the last post there's a hole to the right of the mounting screw. On mine there is a flat head screw between the mounting screw and the attachment point for the choke cable. Do you know if that is normal for a manual choke carb?
I'm going to flip the piece that is supposed to be connected to the choke linkage around in case there is a way to connect it.
I've been going through the old interweb trying to find info on the choke lever on this carb. Mike's Carbs shows only 2 choke levers for the Rochester B carbs and neither of them look like the one on this carb. But neither of those levers have a place to connect the manual choke cable. ????
OK- - - -instead of having the spring clip on the throttle linkage, the throttle cable needs to go through the hole in the shaft and have a round piece of brass with a setscrew in it clamped onto the cable. That allows the gas pedal linkage to slide up and down on the cable freely, but a higher idle speed can be set by pulling on the throttle knob on the dash. Then all you'll need to do is sort out the fast idle cam in relation to the choke bell crank. Some parts are obviously missing, or assembled incorrectly there. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
OK, I can see what you're talking about. I can get that done.
In the photo I attached showing the choke rod where would the choke cable get attached? I don't see anything on it where the cable would go. It also doesn't show any bracket that the choke cable would be attached to.
The fast idle cam was originally attached to the carb with a lock washer behind it so it didn't move. I'm guessing that is not correct. I've flipped it over and removed the lock washer so that it now moves along the raised area of the screw that hold it into the carb.
I've got some relatively unmolested examples of Rochester B's stashed away out in the shop. There's also a bunch of "parts carbs" that will never go back into service out there. As soon as today's ice/snow storm moves on, I'll be glad to see if I can post some pictures, or maybe send you the parts you need to get yours going. Send me a PM with your snail mail address, at your convenience. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
Thank you very much. I'm going to play around with the choke lever to see if there's any configuration I can get it into where it would accept the choke rod from the fast idle cam. I'll get that PM to you.
That picture on the left side of your attachment is exactly what the top of my carb looks like. The choke is now operated via the cable that is shown in the photo. On mine the fast idle cam was secured to the body of the carb with the original screw AND a lock washer so it didn't move. There fore when you pulled out the choke lever nothing happened to the throttle mechanism. There is a separate throttle control cable in the cab but at this point it's frozen to its metal wound casing. At this point the engine is running and I can control the choke with the cable inside the cab. I have it up for sale and someone is coming to look at it tonight. If he buys it I'll let him know about what, as Jerry says, is a mixmaster (or Frankencarb).
Jerry, you seem to be pretty switched on with these Rochester carbys, so would you be able to give me or point me in the direction of the jet sizes for the carby for a '54 235 engine please? Many thanks, Bob
