Gas petcock normal and reserve tank line replacement

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Alex Parmenter
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Gas petcock normal and reserve tank line replacement

#1 Post by Alex Parmenter »

In the process of getting my 54 project back on the road, pulled the gas tank and cleaning out 40 year old gas etc. I’m rebuilding the petcock, but the two short lines inside the filter sock inside the tank have pretty much completely dissolved to leave two short stumps. Sure a few years ago that I read an article or post on replacing the lines, but have searched and can’t find it. Pic for reference and is a VW one from Samba, my petcock now full disassembled and soaking in carb cleaner. Any tips on replacing the long and short lines, just a press fit?

Thanks!
B53023C0-FE74-4F9C-90E3-F0F01CB64AE1.jpeg
Always searching for parts for my Oct 54 Pre A coupe including these:
2 piece engine case to #336XX
Gear knob
Front bumper
Passenger sun visor
Bosch SH/ZS4/1 Ignition switch
Vigot jack (late 54)

 

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John Brooks
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Re: Gas petcock normal and reserve tank line replacement

#2 Post by John Brooks »

After its clean remove the nut, then you can solder new tubes to the old ones, last time I got the brass tube from the model or hobby store, get some Good quality flux and a micro torch. I ground off the old tube down to good round material, cleaned the inside with a drill bit and slid the new tube inside the old one and soldered then together. It will sweat together like a water pipe. Clean and bright brass on both then the flux. The old pipe was pressed in but will be frozen in the alloy body by corrosion, so easy on the heat on the original pipes. Heat the new ones and hold the solder at the joint, it will flow all the way around.

Not too hard to repair you can buy the rest of the repair kit and new screen from most larger venders.
John Brooks

62 Roadster
66 912
84 Cab
getting pushed around in porsches since 1965

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James Davies
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Re: Gas petcock normal and reserve tank line replacement

#3 Post by James Davies »

Alex, make sure your Petcock is original to the car before spending too much time repairing it. What '54 chassis number do you have?

I ask because in spring of 1954, Porsche stopped using the 1952 VW-type petcock as in your photo above (for 8mm fuel lines) and replaced it with a bespoke Porsche one that had the same 8mm lines, same threading to the fuel tank, but a longer internal filter element and bowl clamped via a wingnut at the bottom. These were at least in use by coupe 51942.

Eventually, from coupe 53527 and cab 60816 onward (early 1955), they changed the petcock again, keeping the long filter bowl, but using a larger diameter threaded screw to attach it to the fuel tank, which means the later fuel tanks are matched to the later petcocks, and the early tanks, like yours, will only work with the early petcocks - either the VW one or the Porsche one which was only used from early 1954 to early 1955. All 1954 model year cars have the 1-year-old petcock.

So if yours looks like the short one pictured above, it might be a replacement from a VW. If your car is an early 1954 calendar year car, it probably had this type originally, and you can find these pretty easily because they were used on VWs until late 1952. Look for ones designed for 8mm fuel lines. VW switched to 6mm fuel lines in late 1952, so the Porsche and VW ones diverged at that point.

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Alex Parmenter
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Re: Gas petcock normal and reserve tank line replacement

#4 Post by Alex Parmenter »

John and James, many thanks for the replies and tips. Will get the new pipes soldered in this weekend and should be good to go as i have the rebuild kit ready also.

James sorry pic was misleading as thats not my petcock, just used a pic of vw one to illustrate the pipes. Pic of my one attached below, my car is Oct 54 build, gas tank appears original and has Beck fuel sender etc. heres pic of mine and has vw marking, so assuming its a replacement as per your info, but also has longer fuel bowl?????
E0ECD6AA-D8B4-4069-8892-1F15A58CB8F1.jpeg
ACDD8664-AEA1-4BE9-93CD-5FF666822BDA.jpeg
Attachments
0F860B51-2A00-4ED0-923D-CA21FF1C2273.jpeg
Always searching for parts for my Oct 54 Pre A coupe including these:
2 piece engine case to #336XX
Gear knob
Front bumper
Passenger sun visor
Bosch SH/ZS4/1 Ignition switch
Vigot jack (late 54)

 

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James Davies
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Joined: Thu Aug 15, 2013 9:15 am
Location: Heidelberg, DE

Re: Gas petcock normal and reserve tank line replacement

#5 Post by James Davies »

Yup, yours looks original to your car. 1 year only they used this long version with the VW threads. By mid-1955, the threads attaching it to the fuel tank changed.

So yeah, you'll definitely want to repair this one. More than you ever wanted to know about fuel petcock rebuilding for pre-A here

viewtopic.php?p=274849

If you want to buy a replacement, this is probably the same one:

https://www.thesamba.com/vw/classifieds ... id=1473559

Verify the threads though if you try to purchase.

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Alex Parmenter
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Re: Gas petcock normal and reserve tank line replacement

#6 Post by Alex Parmenter »

James, many thanks for all the info and the confirmation that I’ve got the correct 1 year petcock! Rebuilding this weekend, and thanks for the link to the thread, very useful!
Always searching for parts for my Oct 54 Pre A coupe including these:
2 piece engine case to #336XX
Gear knob
Front bumper
Passenger sun visor
Bosch SH/ZS4/1 Ignition switch
Vigot jack (late 54)

 

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Al Zim
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Re: Gas petcock normal and reserve tank line replacement

#7 Post by Al Zim »

WHAT A GOOD IDEA! making a petcock out of aluminum and have parts that will clog because that is not the way to have a filter nor to have a valve that controls the fuel to be made out of cork and rubber? al zim Do you need a reserve when you have a fuel gauge (that works) in the car? Evidently Porsche thought that some people did!
Last edited by Al Zim on Fri Feb 03, 2023 2:30 pm, edited 1 time in total.
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Greg Bryan
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Re: Gas petcock normal and reserve tank line replacement

#8 Post by Greg Bryan »

I had a VW bus where the long pipe rotted off but the reserve was still in place, far above the other outlet - that caused me some problems before I figured it out as the bus didn't have a gas gauge.
Greg Bryan

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