Last fall, towards the end of the New England driving season, I was noticing that the car seemed to be running around 160. During the hotter weather it always seemed to run around 180-190. That 160 seemed a bit cool to me, so over the winter I decided to check my thermostat. I was wondering if there was even one in there. What I found installed was a Windsor style 160 thermostat.
I got a Robertshaw 180 installed, refinished my rusty cooling pipes and put in a full set of new hoses. I installed the revised fan relay set up along with supplemental grounds for the Kysor brand fan motors. I also figured out why the previous owner said the manually switched sucker third fan never seemed to help much. It was wired backwards and it pushed back against the first fan. They all spin like turbines now. Noticeably faster than with the diodes in there before.
I first filled it up with plain water to test it and check for leaks. After it warmed up only one fan came on. It ran that way long enough for me to seriously wonder if I'd mucked something up. Just as I'm pulling out the meter to start doing some checking, the second fan came on, ran for a few minutes, then shut off. After a little longer it settled into a regular cycle, which tells me that one fan is almost all it needs. If I run the manually switched third fan the second fan just doesn't come on. All the while my temp needle is right on the "0" of 180. I'm pretty happy with all this.
Now that I'm back on the road I'm noticing that the first fan evidently comes on while I'm moving because it's running when I come to a stop whereas it used to take a few moments at a stop before it called for fan. I guess the fan probably isn't drawing much current if the car is moving since the fan blades are being driven by the wind but do they like running constantly?
I'm wondering if my radiator fan thermostats are too low, ie; calling for fan before it's really needed. I've got a brass six (?) core two pass radiator with threaded in thermostats. I'm going to check to see what they're rated at, but what should they be? Are there different values available?
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