Blog Entry #28 October 1, 2013 – Overheating Challenge & Jacob Lake

Woke up at dawn Tuesday, October 1st at our cabin in Springdale, Utah on the southern edge of Zion National Park.  Our plan was to head out toward Grand Canyon National Park, the 11th National Park on our Trek.  We had stayed up until midnight the previous evening to hear if they would be closing the National Parks.  Sure enough, they did close the Parks.

We were undeterred in our quest to at least reach the entrance to Grand Canyon National Park as a requirement for our Trek.  Two things did affect the route to the Canyon however.

We had learned the previous day while in Zion National Park that if they did close the Parks, the main east/west highway across Zion National Park would remain open.  However, there was concern by a fellow traveler that National Park personnel might not be immediately stationed at the highway entrance to screen large vehicles for their ability to navigate the tunnel along the route.  If this were the case there could potentially be a major traffic jam at the tunnel, as there is really no place for unsuitable vehicles to turn around in that vicinity.

Also, the reason I had gotten up so early the morning of the 1st was my concern over the erratic engine cooling system behavior the previous few days.  I wanted to see if my tinkering had solved or at least mitigated the overheating problem.  Unfortunately, a short drive down Springdale’s main street at 7am demonstrated the problem of overheating during warm-up was worse than ever.  So I waited on the side of the street until the engine temperature settled down and then drove back to the cabin to set a plan of action with Jean’s help.  The night before, I had put out a request for suggestions for a solution to our overheating problem on an on-line Jeep owners forum that I recently joined – great folks.  By morning a number of members had come through with possible causes and suggested fixes.  The most plausible cause was a sticking coolant thermostat.  This thermostat senses the coolant temperature in the engine and allows (or is supposed to allow) cooler coolant from the radiator to enter the engine’s coolant passages when the engine temperature exceeds the opening temperature prescribed by the selected thermostat – in my case 160F.  If the thermostat fails to open as prescribed, insufficient cooler water moves from the radiator to the engine and the engine temperature will continue to rise past the boiling point of the coolant (~240F) eventually to the point of causing catastrophic damage.

Second Guessing:  A decision that I had to make for each of the critical components on the Jeep (e.g.: carburetor, distributor, water pump, generator, etc), was whether to make the 10,000 mile Trek using components that had performed well on previous shorter trips, or replace them with new or rebuilt parts.  In the case of the thermostat, I figured that since I had the old one out during the engine rebuild, why not put in a nice new one.  There is no knowing if the old one would have lasted the Trek, but the new one apparently did not.

Assuming that a sticking thermostat was the primary cause of the overheating, I made some calls and found an auto repair shop in La Verkin which lay along our alternative route to the Grand Canyon.  Thankfully, they said that they would be able to obtain and install a new thermostat.  When we arrived at their location at around noon they took us right in and a gentleman familiar with older cars took great care in installing the new thermostat.  After an excellent lunch of handmade tacos at a local restaurant we were happily back on our way.  (Unfortunately, we were to find out a few days later that engine damage – albeit reparable, had indeed occurred during the high temperature excursions.)

Auto repair shop in La Verkin that changed the thermostat

On the way to Jacob Lake, Arizona we spotted an early jeep station wagon in the employee parking lot of a local electrical utility company.  The owner was out working in the field, so we did not get to compare notes.  Mostly to break the boredom of long stretches of 55mph driving, I am constantly on the lookout or Jeeps of our vintage – either on the road or rusting in someone’s back yard.

Jeep Sighting on the way to Jacob Lake, Arizona

Arrived at our Jacob Lake, Arizona lodging around 5pm I think.  I was never quite sure what time it was in the central west.  Some regions honor daylight savings time, while others do not.  It is not uncommon to see clocks behind hotel registration desks labeled “correct local time”.  Our iphones and GPS try to keep up with the local time, but only do a reasonable job of it.  Running clocks cannot always be relied upon, but at least stopped clocks show the correct time twice a day.

We had selected Jacob Lake (never did see a lake) for the evening because it was strategically located as a launching point to either the north rim, or at considerably greater distance, the south rim of the Grand Canyon.  We were aware that Grand Canyon National Park was closed by the Government shutdown, but felt compelled to “touch bases” as a token of our adherence to the route of the original 1920 Park-to-Park Tour route.  We would decide how to achieve this the next morning.

10-1-13 On the way from Zion National Park to Jacob Lake, Arizona

10-1-13 Vermillion Cliffs on the way to the south rim of the Grand Canyon

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