Fuel inlet nut gasket

[tucsonjwt]

I have a leaking fuel inlet nut on the Quadrajet for my 1983 Chevy C20 truck, carb number 17066558 1581.  It does not appear to be stripped, nor does the fitting on the end of the hard line entering the inlet nut.  I got a new inlet nut gasket and installed it but it leaks worse than before installation.  I think the problem is that the washer does not extend past the end of the inlet nut, so the washer does not seat against the inlet nut housing.  I can feel the end of the inlet nut threads when I run my finger over the end of the inlet nut.  This is the white nylon style washer.  Where can I buy the correct washer and shouldn't it extend past the end of the inlet nut?  Thanks.

[429bbf]

tuscon the washer should not extend past the end . look down in there and see if your sealing surface has a groove or erosion. mark the nut and screw it in with and without the washer to see if it is actually touching or the threads are your problem and you dont realize it. also check to see that there is not an old washer down in the hole. just a couple of suggestions.

[429bbf]

forgot to add  that carb no. makes no sense to me . is it possible that it takes the washer on the outside or it seals on the outside taper

[tucsonjwt]

OK.  I guess the center of the inlet nut fits into the center hole of the housing without interference. The contact surface looked ok to me, but I will check it again.  I am now suspicious of the flare nut on the end of the hard line.  Is there any special technique for tightening that nut?  I keep slight outward tension on the hard line when tightening that flare nut to keep it lined up on the inlet nut.  I see no evidence of cross threading on either component and they thread on straight and fairly easily.

I bought this truck used and don't know what the carb number means.  I looked up the number once and I think I read something about a motorhome application, and since this is a camper special pickup that might explain it. One website said GM did not always follow the number identification rules. 

[tucsonjwt]

I checked the threads on both the filter housing and the hard line fitting.  All threads had a very fine residue of previous application of teflon tape.  I cleaned all threads with a fine wire brush and carburetor cleaner and everything sealed up nicely.  'The primary problem was that the large amount of teflon tape residue on the hard line fitting prevented it from fully threading into the filter housing, causing the leak.  Thanks.

[Ethan1]

forgot to add  that carb no. makes no sense to me . is it possible that it takes the washer on the outside or it seals on the outside taper

 That carb is off a '80-'84 Chevrolet/GMC Truck/Motorhome 454cid engine.

[Ethan1]

I checked the threads on both the filter housing and the hard line fitting.  All threads had a very fine residue of previous application of teflon tape.  I cleaned all threads with a fine wire brush and carburetor cleaner and everything sealed up nicely.  'The primary problem was that the large amount of teflon tape residue on the hard line fitting prevented it from fully threading into the filter housing, causing the leak.  Thanks.

 Yep, teflon tape will do that.