Fuel Filter - Petcock question

[Jim Clement]

I was fortunate to pick up a spare fuel petcock for a very reasonable cost - free.. but it appears to be different than the one from my car.
I have a 1957 coupe, an early 57 so a T1
The one I took out of my car - shown as the one with the larger body, has the outlet part with stripped treads, so it leaked.. I replaced it with a new one.. but now looking to make sure I have a spare one, and looking to have one of these two as my spare.

Any idea on what this smaller petcock is from ?
second question - any thoughts on how I can repair the stripped treads.. both pars appear to be soft aluminum.

[Jim Clement]

One measures 26 mm across the other is 32 mm
are they adaptable to a 356 ?

[Al Zim]

If your leak persists make sure you have plenty of insurance on the car and on your home/'shop. Zim

[Mike Wilson]

Offhand, Jim, I'd think if the threads of the petcocks fits on your gas tank, they look usable. It does look like the reserve pick up tubes are different lengths. I wonder about the length of the selector rod, however.

Mike

[Vic Skirmants]

That is for a pre-A.

[Al Zim]

You need a new petcock so you can shut the gas off into the carburetors when the 356 is resting since the carburetors will always leak. Evidently this was not a big deal at Porsche since the 912 carbureted pushrod cars did not have a petcock on the tank. Oh Well!

[Donald Zingg]

Any idea on what this smaller petcock is from ?

As Vic pointed out, it was introduced as a pre-A part, which would have occurred around May 1955 when the P-356 fuel tank got a larger diameter outlet on the bottom. That fuelcock is illustrated in the August 1956 P-356A factory workshop manual on page F 28.
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[Jim Clement]

Many thanks.
I have a friend that is restoring a Pre A to a very high standard, so may be able to use this..
Does anyone have an exploded view that would show the make up of the gaskets and washers that are holding the part number 6 in place ?

[Donald Zingg]

Here's a pic of the internal parts of the valve.
BTW - that fuelcock will fit the tank in your T-1 but will not fit your friend's pre-A tank if he has a 1954 or earlier car.
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[Jim Clement]

Donald, all
are you sre the parts that are circled area part of this petcock ?
when I am assembleing mine, it all seams to work .. without these two parts.

Thoughts ?

[Donald Zingg]

Yes, the parts you circled are required. The coil spring presses the valve disk against the cork gasket firm enough not to leak but still allows the valve to rotate. The bushing acts as a seat for the pressure spring, the bearing for the valve stem, and flange for the snap ring that holds the assembly together.

If you're trying to assemble all the parts but cannot compress it enough to install the snap ring, then you just discovered the replacement cork gasket in the rebuild kit is twice as thick as the OEM gasket. There are a couple threads discussing fuelcock repairs in the Pre-A Corner including one simple method of sanding down the replacement cork gasket to fit properly.

[Jim Clement]

Yes, the parts you circled are required. The coil spring presses the valve disk against the cork gasket firm enough not to leak but still allows the valve to rotate. The bushing acts as a seat for the pressure spring, the bearing for the valve stem, and flange for the snap ring that holds the assembly together.

If you're trying to assemble all the parts but cannot compress it enough to install the snap ring, then you just discovered the replacement cork gasket in the rebuild kit is twice as thick as the OEM gasket. There are a couple threads discussing fuelcock repairs in the Pre-A Corner including one simple method of sanding down the replacement cork gasket to fit properly.

Yes - Don, you are correct.. I cannot compress it enough..
how do you make it thinner and still be smooth enough to make the seal ??
will 100 grit sand paper do the trick ?