Aug 6th

Wow, what a difference!  Steve had suggested that I change both the thermostat – to a 180 degree one – and the fan clutch.  I don’t really have the time or place to change the thermostat since campgrounds don’t want you doing that and, while we could do it in a parking lot I figured why not just change one thing at a time anyway and change the clutch.  The Hayden fan clutch was so quiet that Carol didn’t think it was on.  When I say “quiet” I mean when compared to the Delco.  The trip can continue in peace – it was so bad that it it was making the trip less than enjoyable.

My observations are that the Hayden seems to come on at a lower temperature but turn at a much reduced rate from the engine RPM.  I would have to guess, based on the noise and the engine temperature readings (more on that later) that the Hayden’s rate of rotation percentage goes up with the temperature. The Delco on the other hand seems to be either on or off – a close match to the engine RPM even at 60mph.  The result is noise – lots of noise with the Delco – and relative quiet; you can hear it but it is hard to distinguish from the engine noise.

The engine temperatures were much better and steadier with the Hayden.  With the Delco, the engine temperature would oscillate between about 190 to 210 and, occasionally, it would get to 215 if it was really hot and we were climbing even an average hill in New Mexico, Texas, Oklahoma and Kansas.  With the Delco the temperature virtually never stayed the same for any time at all – it was always moving either up or down.  With the Hayden the engine temperature was very steady – at just under 200 – and would only move a little if I was climbing a hill.  It never got above 205.

The difference in the weather was pretty notable.  With the Delco we drove through ambient air temperatures from low 70’s to 105.  When the temperature would get to 80 the cycling would begin and the only thing that changed was the rate of temperature climb – when it was hotter the engine got hotter quicker.  Today, we left Kansas City with the temperature at about 80 and spent most of the day with it at around 85 and it got to 91 for a little while.  The engine temperature would stayed steady throughout the day.