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The dash on the MGA was still in the original red paint. When the car was new, the exterior was black with it had a red interior. The dash was red to match that. The paint was faded and chipped, there were some extra holes etc. The dash had to come out and be repaired and sprayed the same red as the exterior. I also wanted to clean the instruments, rewire etc. Getting the dash out is not bad job on an MGA. One place to start is the water temperature/oil pressure gauge.

Original state of the MGA dash when the car was purchased.

The water temperature gauge and oil pressure gauge are both provided in one instrument on the MGA. The water gauge works through the expansion of ether when the engine warms. There is an ether filled bulb that screws into the head towards the front of the engine, and a capillary tube that carries the expanding ether up to the mechanical gauge. What this means is that under no circumstances should you cut or rupture the delicate tube leading from the engine to the gauge. If you do, your will either need a pro to repair the line and add new ether, or you will need to buy a new gauge with intact line and bulb.

You remove the temperature sensing bulb by unscrewing it from the head. Be careful that the fitting that you are unscrewing has not become stuck to the capillary line by crud. If it has and you start twisting, you will break the line and will need either a costly repair or a new gauge. There were various ways that MG ran the capillary line from the front of the engine to the bulkhead and then to the gauge. Many are run along the engine, attached to the bottom of the heater valve at the back of the engine, up to p clamp on the heater shelf and then through a rubber grommet on the bulkhead. You will notice corkscrew twists in the line between the engine and when it attaches to the body. This is to allow the line to flex and accommodate movement of the engine relative to the body. In the case of my car the line ran to the inner fender, was held by a p clamp there, and then ran back along the inner fender to the bulkhead. WHen you remove the instrument you can either push the rubber grommet on the bulkhead back into the interior of the car, or cut it away if it is too stiff. Careful not to nick the capillary tube.

Removing the water temperature bulb and line from the MGA
Attachment of water temperature capillary line to inner fender of MGA. Note coiling of line between engine and body.

Now, once the capillary line is feee of the engine, the body fasteners and the grommet, you want to detach the water temperature gauge/oil pressure gauge and draw it through the dash and towards the rear of the car. The capillary line and the bulb comes through the instrument hole and out towards you from the front of the dash. You can crawl under the dash and unscrew two hand nuts from the bracket at the back of the gauge. Take the bracket away and disengage the oil pressure line from the back of the gauge. You can then pull the gauge off the dash and towards you as you sit in the passenger seat. Take it slow and feed the capillary line through and remove the line and bulb carefully. Once the gauge is out you can loosely coil the capillary line so you can store the unit.

Fixing bracket and light removed from back of water temperature and oil pressure gauge. The two lines are attached to the gauge. You unscrew the oil line, but the water temperature line must remain attached.

Withdrawing the water temperature/oil pressure gauge from the MGA dash. Note that the water capillary line must remain attached and intact.

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