Mechanical Guages and the LS1

[Aussie Mike]

Oil temp next.

The temp guages use a capilary tube. There is a bulb on the end of the tub filled with alcohol or some similar liguad that when heated expands. This creates pressure in the capillary tube which is read by the guage.

The problem is that the bulb is quite large and the adaptor supplied has about a 7/8" NPT thread on it, it's huge. However The threaded ferule that holds the bulb into the adaptor is only a 5/8" UNF thread. This gives a few options for making my own adaptor to fit a smaller hole.

The US LS1 motors are equiped with a sump heater. This basically keeps the oil warm on freezing cold nights when the car is parked. Turn the key in the morning and the car starts easily with the warm oil being a bit thinner. The sump heater screws into boss in the side of the sump with a 20mm thread. We don't need no stinking sump heater in sunny Australia (although you have to wonder in Melbourne sometimes) So this turned out to be an ideal spot.

I machined up an aluminium do-hicky to take the 5/8" capillary bulb fitting and adapt it to the 20mm thread. A copper washer seals it against the boss and a coating of loctite liquid thread sealer adds some insurance.