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Prestolite torch is acting strangely

my prestolite torch is acting strangely when I light iti have to keep
adjusting the valve or the flame gets smaller all by itself.I got a
new tip and that didn’t help I can’t figure it out.

Chris Makin


my prestolite torch is acting strangely when I light iti have to
keep adjusting the valve or the flame gets smaller all by itself.I
got a new tip and that didn't help I can't figure it out.

Almost empty tank ??? :slight_smile:

Easy first, when is the last time the tank was refilled, the first
thing is the pressure is getting low in the tank. and due to the
temp of the tank and the acetylene gas out gassing from the acetone
it is dissolved in the tank over night. Causes the flame to do funny
things. If the tank was purchased used, and the owner said it was
full most likely it wasn’t. Acetylene tanks contain gas @ 225psig at
a temp of 70"f is considered a full tank. It is a low pressure tank
compared to oxygen, hydrogen, argon, tri-mix, helium etc which are
considered high pressure.

The diaphragm in the regulator and the spring that controls the
setting for the flow is getting old and tired. Or there is another
problem with the regulator internals. Take it in to get serviced.

Prest-o-lite torch part are pretty much inter changeable with the
other brand parts of air acetylene torches, Goss, Uniweld etc. since
they let the patent lapse years ago for a short while. everybody
duplicated their torch rigs.


Finally got some about the Prestolite regulator.

ESAB is still making the Prestolite regulators for the Acetylene B

They took over from Linde, who first made the Prestolite torch. In
fact, my regulator still bears the name “Linde,” as well as
Prestolite, which shows how old it is.

I just spoke to the technical people at ESAB. They are still making
them, but do not sell them directly, but gave me the name of a local
distributor. The number of the regulator for an acetylene B Tank is
R411B. They said one could order them from any welding supply place.

My old regulator was obviously in need of retirement after over 30
years of faithful work. I ordered a new one, which should arrive next
week. The cost is around $70. It varies from dealer to dealer.

I was having problems with the gas seeping through even though I had
shut the tank down after working with it. As the knob on the torch
was closed, there was no leakage of gas, but the dial indicated that
it was flowing.

First I thought it was a defective tank. Then when the same thing
occurred with a newer tank, I figured it has to be the regulator.
Poor old thing was just tired.

I did get some interesting on the Prestolite regulators.
Unlike other regulators,I was told by the technician not to back it
out when shutting down for the day, but to leave it on the "B"
setting. This does fly in the face of what I was told by others, as
well as how one shuts down other regulators—such as the one on my
Silversmith torch. However, as ESAB manufactures the Prestolite torch
and regulators, they should know how to use them.–or at least I hope

Alma Rands


30 years is a long time for a regulator, and I suspected that was
the problem. For the Acetylene B tanks, or any tanks, I strongly
suggest that you acquire a dual regulator; one that reads the
pressure in the tank and the other in the line. A line regulator will
tell you need to change your hose, and if you have had that regulator
for 30 years, I bet your hose needs changing too.

Old rubber will crack and degrade over time. You might not do
anything to it, and it’s not like a car, hose, but humidity, with
changes in dryness and humidity, while you might not feel the subtle
changes, over time can crack and damage a hose, just slowly.

Last week, the safety expert from Airgas, the company that bought
out Linde, was at my studio looking over my tank, hoses, etc. I’ve
been working with this person for a long time, and he is THE expert
for safety for this company. I will inquire about the Prestolite
regulator and its position when the tank is bled and idle. Regulators
with a T bar ABSOLUTELY must be backed out when the line is bled out
after use.

When you run a school like I ran Metalwerx, our number one issue was
safety, for our students, our instructors, our community of
metalsmiths, staff and visitors.

I cannot stress safety enough when working with gas. That doesn’t
mean you have to be scared, but be vigilant and informed. Actually
I’m more scared crossing the streets in Boston then having a full
tank of Acetylene in my studio!


Karen Christians

Karen thanks for all the valuable My hose is new. I
change hoses regularly just to be on the safe side. It has only been
recently that the regulator has been having a problem. I have already
ordered the Prestolite regulator for the B tank, and it is due to
arrive next week… Hopefully, I will no longer have any seepage of
acetylene. If I do, then I will follow your recommendation and get a
dual regulator. I was unaware that they could be used with the
Prestolite torch, as I thought the fittings might be different.

I have a dual regulator with a T Bar for my Smith Silversmith torch,
and I do back that one out when I am finished working. The Smith is a
great torch but the Prestolite torch handle seems to be more
comfortable in my hand, so I tend to favor it…

I will appreciate hearing what the safety expert from Airgas says
about the Prestolite regulator. Thanks again Karen,for taking time to
send me this