I just installed 2 electric fans. I used 2 of the the spal fan relay harnesses with the thermostat. I installed the thermostat in the water pump housing and the fans are always on, I know its not hot enough to activate them, the van was sitting 2 hours. If i take the thermostat out of the water pump housing and connect the wire the fan wont come on. Has anyone else had this problem? I have 2 of the thermostats and they both do the same thing, so I can rule out a bad thermostat.

 

what temp is the tstat supposed to turn the fans on? usually thoose electric fans are meant for gas motors and need to come on at a cooler temp. our trucks have a 195 in it and unless you have a 94-95 which has a 203 in it. and they always flow just a bit of coolant so there could be a small stream of warmer fluid coming through.

 

I tried the 195 on 175 off and the 185 on 165 off. After letting the van sit all night I turned the key forward and the fans still come on, argh!!!

 

hmmmm can you only wire the tstats one way? is it a premade harness?

 

It is a SPAL fan relay harness kit,and the directions say to hook up the grey wire to the end of the thermostat. It sems that the fact I can hold it in my hand,and they dont come on,like it should, has me wondering if it has something to do with being groounded. The directions show an optional switch that can be spliced into this grey wire and then to the negative of the battery. I dont need the switch so I didnt splice this in. I wonder if i should try a wire from the grey to the negative of the battery,omitting the switch?

 

I tried the grey to negative and nothing changed. I noticed that if i touch the grey to any part of the water pump it turns on the fans. I also put the grey to the factory temp sensor in the water pump and it seemed to work. The fans didnt come on until about 160 or so which is fine but then I went to look at the temp gage and it wasnt working anymore. I unhooked the grey from the gage and the gage works again, so I am back at square 1.

 

I found out that the thermostat sensor in the water pump is grounding out on the water pump housing, the sensor is too long for my airtek water pump. I bought a radiator mount adjustable thermostat.Everythings working fine. The hottest the coolant got was 210 doing 70 mph at 80 degrees. Stopped at a light it cools down to 195-200 degrees. Are these temps acceptable?

 

yeah temps sound good right round 200 is where it needs to be. good to hear ya got it all worked out!!

 

Thanks Jake