[TR] Thoughts on steel vs copper gas lines

Randall TR3driver at ca.rr.com
Fri Apr 5 01:07:21 MDT 2013


> One of the things I need to do is run a gas line from the 
> fuel pump to the carbs and the short piece from the fuel pump 
> to the line going back to the tank (about a foot I guess). I 
> am thinking I should use a steel line as it will be less 

Steel was original, and what I would be inclined to stick with.

One problem with "copper" is that nothing is really made with pure copper.
And what alloy you get is important to things like resistance to work
hardening (which can lead to cracks) and so on.

>  Also, what dia. should I use for 
> the steel vacuum line from the carb to the distributor?

The size isn't critical, just whatever works easily with your connections.
IIRC the original line on a 4A was about 3/16" od and had push-on fittings.
I did use copper there (alloy 122 I think) because I couldn't easily source
steel line in the right size for my TR3A (with 1/8" compression fittings) at
the time.  Now I believe the usual suspects carry it.

> I am also considering installing a shut off valve between the 
> pipe from the tank and the fuel pump, (maybe right on the 
> pump) for the long winter nap so gas doesn't leak anywhere.

That was standard equipment on the early cars, but the valve was mounted to
the frame and had a hard connection to the line to the tank (so you could
turn the valve off to replace the soft line to the pump).  Seems like a
great idea to me; not sure if they discontinued it to reduce costs or
because the valve they used was more prone to leak than anything else <g>

Randall


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