1969 GT500 Gas Tank Vent Tube / Fuel Vapor Line

[stangs-R-me 120]

My custom exterior vent tube line is done that connects to the pre-bent Classic Tube GT500 Vent Line in the trunk.  

Parts:

1) 168-05-04 Brass 5/16" Hose Stem to 1/4" Male Pipe

1) 207S-04-04 Brass Bulkhead 1/4" FM Pipe Coupling

1) 402-05-04 Brass 5/16" Inverted Flare to 1/4" Male Pipe 90Deg EL

1) 40" Long piece of 5/16" Tubing with inverted Flare Ends (cut about 11" off and beaded the end for hose)

1) 1x1"x1/2" Corner Brace & Small Cushion Loop Clamp.   A 1/4-20 bolt replaces the one gas tank bolt, along with a 1/4" USS Flat washer, thin jam nut & nylon insert lock nut on the corner brace.   Added a 10-24 threaded insert to the one leg of the corner brace and a 10-24x5/8" Hex Bolt, washer & lockwasher holds the clamp to the corner brace. 

3) 5/16" x 2.5" Long Fuel Line and 5 Spring type hose clamps (both ends of pre-bent classic tube line in trunk and the section that hangs down below the valiance). 

1) 168-05-02 5/16" Hose Stem to 1/8" Male Pipe, custom 5/8" OD x 13/32" ID Washer & Gasket, and McMaster 5530K14 Teflon Insert 1/8" Pipe Locknut (at filler neck).

With the passenger exhaust tip off, I had no problem getting this all in there.

 

[Vicfreg 771]

Really nice work and attention to detail, well done!

[Vicfreg 771]

What kind of 5/16" tubing did you use?

[stangs-R-me 120]

Thanks for the kind words, I'm real pleased with the results.

The in the trunk tube is the pre-bent line from CJP / Classic Tube mentioned in the first post.

The outside inverted flare tube I got from Autozone ... part # PA-540, guessing PA stands for "Poly Armor" which is the outer bronze coating 5 = 5/16" and 40 is 40".   Never seen tubing like this before and I even asked if they had regular galvanized tubing and the counter guy said no, but maybe it could be special ordered.    I don't normally shop there, but was running late and my regular store (Carquest, know the owner real well) had already closed.

Doug

[stangs-R-me 120]

Part of this GT500 recall / modification is that you need to change of the "vented" type gas cap for a "non-vented" one.   GT500's had the "vent-dent" in the neck just like all other '69-70 Mustangs (instructions even state to flatten the dent out), so theoretically it should have already came with a non-vented cap.   

With the "vent-dent" in the neck, the O.E.M. standard '69-70 Screw-On Mustang gas caps were all non-vented as are the repro's.   Mach 1 & GT POP-OPEN caps were all non-vented as would be the repro versions if you install the now "show-car only" plunger assembly instead of using the screw on cap they also supply with the kit.    I have a Scott Drake repro GT pop-open on my car and I assumed the screw-on cap supplied was non-vented, but it is NOT so the search was on for a non-vented version.  

I would assume '67-70 Cougars had the vent dent neck too, so I went on WCCC site and found pics of used necks ... '67-68 does not appear to have the vent dent, but the 1969 and 1970 ones did.   So you would think there would be vented caps for '67-68 & non-vented for '69-70, but instead WCCC (and Stant) just list the same vented / anti-surge one for all '67-70.   Which I suppose vent dent or not a vented cap will work ... just don't try and use a non-vented cap without a vent dent filler neck.   Searching e-bay and Stant's site, I was not having much luck finding a non-vented cap that would fit.   The common "non-vented" one that does have some Ford applications including 1970 Cougar with CA Emissions (Stant 10632) is a smaller diameter, so it will not work.

The '71-73 Cougar cap (Stant 10810, actually for '71-82 Cougar as well as other Fords) is considered an "emissions cap" and has some sort of valve in it.   This cap fits, and the "valve" allows air in but not out (makes sense as these cars have a charcoal canister to trap fumes), so it is suitable for this non-vented application since the vent tube will do all the breathing.

The cap that came with my Scott Drake repro pop-open is on the left.   As you can see, it is different than the Stant vented cap so obviously made by a different mfr.   Also has no stamping on front stating it is "vented" like the Stant cap even though it has a similar spring loaded valve in the center that definitely vents.

[Vicfreg 771]

 Nice job documenting these subtle but important differences on these darn gas caps.  

 I have two flip down gas caps in both are vented.    I have at least one friend with the California emissions car that has a non-vented gas cap and an elaborate  factory  vapor capture system 

 I do recall there being a lot of discussion about this back in the day, when the Ford Pinto fires were happening.    

Good job!