Gas cap Avanti biz

[A83]

Just ordered a reproduction gas cap from Avanti biz and it does not seem to fit my 83 - am I doing something wrong? 

Edited March 1, 2019 by A83

[WayneC]

Don't have a later Avanti, but my guess is it has something to do with unleaded gas and emissions, that the fuel tanks made for unleaded fuel have a different (smaller) filler tube specifically to prevent use of the old vented caps and pump fueling nozzles. Dunno when Avanti made that change. IIRC, when unleaded gas became law in the mid-70's even the fuel pump handle & nozzle assemblies were changed out (for a smaller diameter filler nozzle) so that leaded gas could not be pumped into an unleaded-gas vehicle by mistake during the transition (the old larger-diameter nozzles would not fit into the new filler tubes). If you could put an unvented cap on a vented-cap vehicle, vacuum would build in the tank and lines (and carburetor) as the fuel is used-up, which in turn would fight the suction of fuel pumps (as opposed to in-tank electric fuel pumps in cars which then need a fuel return line... those unleaded-gas tanks vent via other methods).

Edited March 1, 2019 by WayneC

[Gunslinger]

An '83 would use a non-vented cap if I'm not mistaken...there would be a charcoal canister filter somewhere...not sure if it would be back inside the gas tank compartment or up under the hood.  The smaller gas filler and different cap would have started about 1975 or so.  I don't know the appropriate gas cap for the smaller gas fillers.  I would call either Dan Booth at Nostalgic Motors or Jon Myer at Myer's Studebaker for that information...they are probably the two most knowledgeable people out there on such matters.

If you still have your original gas cap see if there's any readable brand name and numbers on it then go to NAPAonline and use their cross reference function to find correct replacement.  They may even list it under 1983 Avanti.

[Bill Hanlon]

A Stant 10640 or 10491 available at Napa or Advance Auto works. I went through a trial and error search last June. Find a store who has it in stock and do a parking lot trial and error.  They are not expensive $6-7 compared to all other parts on our cars.  

Bill Hanlon

[A83]

Thank you all.  Avanti Parts and Restorations is issuing a refund.  They said the cap fits model years 1963-72.  Very apologetic and nice to deal with thus far and promptly responsive to emails.  I ordered a set of front floor mats with the Avanti name embroidered on them also. Being shipped today.

 

Regards 

Kevin