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I recently got a set of carbs (disassembled) but pretty well bagged and labeled (bags for cylinder one, cylinder two, cylinder three, etc). After getting everything assembled, there was a left over piece in the cylinder 3 bag and I just can't figure out where it goes. It looks sort of like the delivery valve that holds down the pump jet, but it isn't. I looks sort of like the jet holder on the side, but it isn't. I know I need to clean the parts better, but I wanted to make sure I knew how it went together first.
Before I go nuts, can anyone identify it? I don't see anywhere that it can go, and there was only the one piece.
Before I go nuts, can anyone identify it? I don't see anywhere that it can go.
Here is the piece in question with the ACTUAL main jet holder. As stated, it is not the main jet holder and main jet but I still appreciate your response even though it seemed a little belittling. However, if I am wrong, please let me know.
It is hard to tell from the photos/views you posted and nothing to provide scale. The item in the center is indeed the main jet holder. The item on the left appears to be one of the accelerator pump demand valves (Weber part number 64290.005), though it's hard to be certain; you should have six of them. The item to the right might be a main jet, but it's tough to tell from that photo. You may benefit from reading any of the Pierce Manifolds Tuning Manual, Braden's "Weber Carburetors", Tomlinson's "Weber Tech Manual", or the Haynes "Weber Carburetor Manual", all of which are excellent resources.
It is hard to tell from the photos/views you posted and nothing to provide scale. The item in the center is indeed the main jet holder. The item on the left appears to be one of the accelerator pump demand valves (Weber part number 64290.005), though it's hard to be certain; you should have six of them. The item to the right might be a main jet, but it's tough to tell from that photo. You may benefit from reading any of the Pierce Manifolds Tuning Manual, Braden's "Weber Carburetors", Tomlinson's "Weber Tech Manual", or the Haynes "Weber Carburetor Manual", all of which are excellent resources.
Thank you sir! I will certainly look into those manuals. My initial thought was that it is the accelerator pump demand valve, but I have all of them and am including pics of the mystery part alongside the demand valve. My thoughts are that it is a demand valve (possibly by a different manufacturer) but it doesn't make sense why it would be with these carbs. The carbs are from my father's 71 T and he bought them brand new. The car sat for a long time and they got clogged. He tore the one side down and bagged it all up. He didn't buy any extra rebuild parts outside of the standard rebuild gasket/washer set. My one saving grace so far is the right side carb is still on the car, so I may find the answer once I get back to the car (160 miles away) and get that carb. I can't ask him because since that time, he has had an injury and currently doesn't currently have the same capabilities he once had.
All the demand valves match the one on the left of these pics. The piece on the right is the part in question. mystery part is on the right mystery part on the right mystery part on the right
Here is the accelerator pump demand valve carried by Partsklassick. It looks very much like the part you illustrate on the left. Regarding your mystery part, I have found that parts for a given Weber carb are very similar regardless of manufacturer (Weber or PMO). Maybe it is from a different carburetor altogether? Best wishes!
Here is the accelerator pump demand valve carried by Partsklassick. It looks very much like the part you illustrate on the left. Regarding your mystery part, I have found that parts for a given Weber carb are very similar regardless of manufacturer (Weber or PMO). Maybe it is from a different carburetor altogether? Best wishes!
Yes, that definitely matches the ones in the carb. I keep thinking I'm nuts because I can't find a spot for the mystery piece. I've been wrenching for 38 years and I truly appreciate your help and effort. I think the part being in the bag is what makes me wonder why it was there. Based on all the diagrams, pictures and things I've seen online, it certainly does appear to be just a random part - not to this set. I've examined the carb and diagrams endlessly and just feel it is assembled with all the pieces it should have. The "T" originally had the Zenith carbs and I'm wondering if maybe that is a piece from one of those. I'm going to look into that.
EDIT - Just looked. The zenith set up is nothing like that. it's more of a one piece design, so the mystery continues.
08-27-2021, 01:31 PM
Weber 40ida-3c Mystery Part
