well I finally added electric fans today and wired it through a new relay, plan to use the relay ground to switch on/ off


did it all temporary everything worked, got it all run permanent and plug in the temp sensor and hmmm the friggin thing is ground until it reaches 185* then goes open so it is backwards ugh now I got a rover I could drive and made it so I can't




ideas before parts stores close for the night?

 

Normally closed relay? Do they make such a thing?

*Electrical is NOT my thing, just FYI.

 

no the temp sensor is normaly closed, reaches temp and opens so it is backwards to how I need it to work, it is a 1 wire coolant fan temp switch, this is how I have it wired








I know there is someone here that knows wiring and can point out something I am doing wrong

 

gonna try this might just be a matter of using the other output

 

eureka !! switched the fan feed from 87 to 87a works perfect now, tired and wiring do not mix well lol


probly need a higher temp switch though, fans come on 185* shut off 170*


thoughts on this temp range? iirc my thermostat is 185*

 

well just answered my own question, the temp switch needs to be higher, with a 185 stat and 185 switch mounted to the intake the switch never gets cold enough to shut off the stat closes first, rad cools down but engine stays hot till stat reopens never letting the switch cool off


seems I cooked this switch, I will try a higher temp switch but starting to think that aux port is not a good location may need to go back to drill/tap the blank on the thermostat housing

 

Got this all straight, ended up buying a GM fan switch fits almost all 1987-1995 GM engines with electric fans like fuel injected Camero/firebirds

3/8" x18 npt fits in the adapter I bought/ modified for the port in front of the intake

Seems to be 195-215*?

Works fine single wire uses special plug

This is open, goes to ground when it reaches temp.

I do not like the high temp so I am sure there is some smart Chevy guy here that knows a part # for the same sensor that rune 185-195* so I can store buy it

 

Sensor I used

 

This will work if you have a gauge style sending unit. But not cheap.
Electronic Fan Controller 70 Amp


You should be able to get a sending unit from newer vehicle at the salvage yard.

 

All thats nice but looking for the sender in pic but lower temp that I can store buy, that way if it dies I cnstore buy. Replacement not wait a week for it to show up