My 69 Malibu came w/ a radiator that has an electric fan. Previous owner must have gone thru the entire engine bay w/ a Ginsu knife and a huge roll of electric tape as just about every lead had been hacked/spliced. I replaced all the harnesses on the car, and I need to know where to splice into the new engine (or forward lamp) harness to drive the fan. Will I have to tie into the bat lead on the solenoid? It now has a 350 with warning lights (no gauges). Thanks, Brawley

Most electric fans draw too much current to drive them form the electrical system. My fan circuit consists of a temperature switch in the intake manifold, a 40 amp relay, a 30 amp fuse and it connects directly to the positive terminal of the battery. It is totally separate from the vehicle electrical system.

Tom

I have a stock water temp switch in the side of one of the cyl heads, and an Edelbrock RPM performer intake. Any suggestions on how and where to hook up the relay and fuse? Thanks, Brawley

You'll need an aftermarket thermal switch to control the fan. Mine turns on at 185 and off at 170, a stock Summit item, I think it was made by Painless. I put a tee where the heater hose exits the manifold and stuck it there. The relay was an industrial item from McMaster Carr, at 100 amps it's plenty beefy for two electric fans. I have a trunk mounted battery so there was plenty of room where the battery used to set for the relay. The fuse is a standard 60 amp blade type from the local auto supply and it's mounted on the firewall.

The fans work GREAT. I took the car to the Woodward Cruise for the first time this year and it kept my big block cool as a cucumber during six hours of gridlock on a hot summer day.

Tom

http://photos.imageevent.com/tomgriffin/woodward/large/IMG_3803.jpg
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My temp sensor is installed in the rt side head, relay and ground are mounted on the core support near the horn relay. Then all you need is battery voltage to supply the relay, and switched ignition. Summit sells the kit I used http://cgi.ebay.com/ebaymotors/FAN-CONTROL-TEMP-SENSOR-RELAY-KIT_W0QQitemZ260278642700QQihZ016QQcategoryZ33600Q QssPageNameZWDVWQQrdZ1QQcmdZViewItem

Tom and Dave,
Thanks for the awesome information. I didn;t get any further posts on this and almost gave up. I really appreciate the pictures as well. You guys are great! Brawley

I would tie it into the batt junction block on the radiator support behind the battery. Its close and would only require a ring terminal. There are several things in the car that recieve power from it. Just unscrew the nut and add your lead to the ones that are already there and retighten the nut.
Bill