While Nicolas was here (see last week), one of the things that we did was to install an electric temperature gauge so that he could have some sense of the actual temp of his coolant vs. the stock gauge that basically says "ok" or "about to boil over" with not much info in between.

There are many options as to where to put the probe in such a setup, we chose to take an easy route that may or may not stand the test of time.  I post some photos here for others who are keeping track and to open the door to "I told you so" later.  Either giving or receiving (hopefully me giving). 

Installing the probe was darn easy:  the plastic top of the radiator is a thick section of high-quality resin that drilled nicely and was stiff enough for a 1/8" NPT tap to get a good bite.  The thickness is about 1/4" in this area, and not too rounded.  In all I estimate that we had 4 or 5 threads in radiator into which the probe could get a good hold.

Because the probe relies on a ground path through the probe housing, we added a washer and a short wire to a nut on the upper radiator support, the ground wire has a blue shrink-wrap cover.  The top wire goes to the gauge.   The wiring tucked neatly into the corrugated wire sheath as seen, and in general was a clean installation.

To prevent getting plastic bits in the coolant, we detached the top hose and stuck a bent soup spoon into the radiator.  It caught a large amount of plastic from the drilling and tapping.

To help prevent future leaks, we dabbed some silicone sealant onto the threads of the probe.  Normally that's a bad idea- because the probe grounds itself through those threads, but in this case it should help seal and keep the probe from moving against the threads and potentially stripping them (brass is much harder than plastic, after all).

We were worried at the height of the probe, but the radiator sits pretty far back under the bulge of the hood, so there is no contact with the heat-insulation and no need to fret.

Labels: expedition, land cruiser, repair