Bill, you need Freon II, not ether. You will have to experiment with the
amount in the bulb but start with 1.5cc's, that will be quite close. Freon
II boils at 75 degrees fahrenheit, this provides the correct correlation
between temperature and pressure. Keep the freon in your deep freeze and put
the guage, capillary tube and bulb in the freezer, if you have a top loading
freezer this is best so that you can reach down inside and do the filling
while the whole assembly is kept cold. After you have soldered the guage,
tube and bulb together drill a small hole in the end of the bulb and solder
in a quarter inch piece of the tube. Put the assembly and the syringe in the
freezer now and let it cool for a while, the freon should already be in
there, using a syringe fill the bulb through the small piece of tube you
soldered in the end then crimp it flat close to the bulb. Now quickly solder
over the end of the tube near the crimp, if you can do this while most of
the guage is still in the freezer so much the better, while in the freezer
there will be no expansion of the freon and therefore no leakage. I've done
a few of these type of guages on old Packards and Jags, the amount of freon
to use depends on the size if the bulb and length of tube, I think I used
pretty close to 1.5 cc's on the last Jag one I did. Jim.
At 11:13 AM 12/2/99 -0600, you wrote:
>Last night, fueled by Diet Coke and a cat-killing level of curiosity, I
>ripped into the worst of my oil pressure/engine temp gauges. This unit
>had been removed by cutting the capillary tube at the gauge and at the
>sensing bulb. I figured that it couldn't be worth less than its present
>value so why not?
>
>Inside the gauge are two Bourdon tubes. These tubes have a wire stop
>soldered to the free end that buts against an "L" shaped rack. The
>toothy portion of the rack engages a pinion on the appropriate needle
>shaft. A clockwork spring holds the needle shaft/ rack assembly against
>the wire stop. Increasing pressure in. the Bourdon tube straightens it,
>moving the wire stop. The spring ensures that the needle follows this
>movement through the "L" shaped rack. The whole assembly is done in
>copper and brass and is really quite attractive. Obviously there are
>two such movements in the gauge.
>
>At the back of the gauge, the capillary tube and tube reinforcement
>spring are soldered into a brass lug. Heating the area will allow
>separation. Since the capillary was cut already and I don't own a large
>soldering iron, I used a torch with the smallest tip and the gas
>pressures turned way down. even so, when the solder let loose, heated
>gas hissed out of the head piece smelling slightly like ether. I would
>strongly recommend that you use an iron for this. The capillary tube
>goes into the brass lug a good one-half inch so it takes a while to
>melt it free. I then took a long, thin nail and, while heating the lug,
>worked out as much of the solder as I could.
>
>At the other end there is a conical shield over the reinforcement
>spring/capillary tube/sensing bulb junction. this can be opened and
>pried off with a straight slot screwdriver. After my experience at the
>other end, I cut the capillary tube clean with a Dremel to allow any
>trapped gas to escape. The original cut was made with a side cutter and
>had crimped the tube shut. I removed the reinforcement coil on this end
>but left the capillary attached since I am just going to attach this
>short stub directly to the gauge to see if it works.
>
>At the other end of the sensing bulb is a blob of solder. Melting this
>away exposes a small brass pin that has been driven into a hole to seal
>the bulb after filling. I used a Dremel and small bit to cut a small
>countersink into this pin and drilled it out. I now have the end of the
>pin rattling around in the sensing bulb but I don't think it will cause
>any trouble.
>
>Feeling quite proud of myself at this point, I went to my favorite
>hardware store. I was not surprised that they don't carry capillary
>tubing or ether. I was also looking for soldering past. This is a
>small in. of flux with solder in colloidal suspension. You just coat
>the joint with this stuff and heat. Once you see clean solder whetting
>both surfaces you are done.
>
>Tonight I hope to solder the tube into the gauge. I am going to try
>using starting fluid but I don't hold out much hope. It seems that
>modern starting fluid contains more heptane than ether. To seal the
>bulb I am going to try a screw and sealing washer for now and go to a
>more permanent seal once I get fluid that works. A second reason for
>this is that I don't have a large soldering iron and I am a little
>concerned about using the torch one the bulb is full.
>
>After this I plan to submerge the sensing bulb in boiling water and
>attach the needle pointing at 100. I will then use a candy thermometer
>to check calibration. I will also try to find a source for ether, the
>capillary tube, and the reinforcement spring. I believe that Small
>Parts sells a nickel capillary tube that will work but it includes no
>wound wire reinforcement.
>
>Then again Nancy has mentioned that she wants to go Christmas shopping
>so I may have to postpone this work. For some reason she gets nervous
>when she sees me with a torch in my hand and a weird grin on my face. I
>guess it takes all kinds ;-)
>
>Regards,
>Bill Eastman
>
>BTW- Mark- I made 40 last year and have owned my XK-in-a-box for 1
>year. I have never ridden in or driven an XK let alone my own pile of
>parts.
>
>
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