|The MGA With An Attitude
RUBBER GROMMET on the TEMPERATURE GAUGE -- DT-102C
On 9/23/2010, Bill Ham wrote:
"Do you have any suggestions as to how to get the temperature probe through the hole in the fire wall grommet? In the original parts manual there is no part number for the grommet. It is shown as part of the safety gauge assembly. I tried rubber grease. I'll try soap. Frankly I lost my nerve and quit pushing because I'm sure the grommet was made in a kitchen somewhere in China".
You have to use the right grommet, and it has to be new so it can stretch a LOT. It has a large outside diameter, small inside diameter, and a kind of conical bullet nose protruding in the center. Put a little dish washing soap on the pats and push and stretch like crazy. Sometimes they go together without splitting the grommet. Maybe original grommets were better back in the 50's. Today all bets are off on quality of rubber parts. Notice the one in the picture is split.
Good spotting in the Service Parts List. This makes it look like the grommet was originally installed on the pipe before the last end was soldered in the assembly, and a new instrument would always come with the grommet in place. That makes the grommet part of the safety gauge, so if the grommet is shot and needs replacing you have to buy a new safety gauge. Boo, hiss. Furthermore, I've paid a premium price to have a few of the gauges repaired with a new signal line and sensor bulb, but the pro shop never installed a new grommet on the line as part of the process. Also boo, hiss. I suppose when the cars were being built no one expected the cars to last longer than the rubber grommet, or maybe they expected the gauge would fail before the grommet.
That gets back to redefining the repair process to include installation of a new grommet on the pipe prior to soldering. I wonder how long it will take to convince a few instrument repair shops to do that, and to advertise the fact that they do that, so their competition has to do the same to make the sales?
At 06:12 PM 1/25/2015 -0700, Sam Earl wrote:
"I was able to successfully stretch my Moss sourced rubber grommet over the temp gauge bulb and nut by first stretching it over a series of sockets (with soapy water) until I ended up with it stretched over the nose of a 9/16" deep well. The temp bulb fit into the deep well, and I was able to slide the grommet onto the threaded portion of the nut, and then work it over the nut. I warmed the grommet and socket to room temperature, but soaking the grommet in hot water probably would have softened it a bit more".