So my '32 has an electric fan ,puller in a shroud ,it's the only fan I have on the flatty. It's been working great,it comes on when the ignition is on. It's run through an ez 12 circuit mini fuse panel with a 30 amp relay. The other day while at the gg wcn in Pleasanton the car jumped from its normal 170 to 195-200 ,I jumped out shut the car down and figured out the fan wasn't running. No big deal,I checked fuses which where fine,pulled the relay and went and found another one from a vendor.put new relay in and fan ran fine,cycled it a few times all was well,drove back to the hotel w/o any probs. then I loaded it on the trailer ( don't get mad,we had our three month with us so needed the space of my quad cab, I did over 1000 miles during the week of tours) got home and started car,no fan. I initially thought broken wire somewhere but would that be frying relays,fuse was good. I **** at electrical.
Check the wiring at the relay. There may be a bad connection on either the power wires for the fan or the circuit to the relay coil. When you replaced the relay you could have "fixed" the bad connection for a short time.
A broken wire will cause the fan to quit running, but not fry a fuse unless it is bare and grounding. It is possible the fan motor bearings are dry or shot, causing it to pull more current, blowing the fuse. Try spinning the fan by hand. Does it spin freely? If not replace it.
One of two things. Fan is beginning to drag as suggested and is over loading the relay or junk replacement relay. Click on this and see how to test a relay http://www.youtube.com/watch?v=3JB63ebFfgU
If you run an electric fan, I'm a huge fan of the Centech fan controller sold outta Speedway. Adjustable on/off temp, manual toggle, LED, AC trinary support, and if you already run an electric temp gauge it just takes the signal off that wire so the whole install is under-dash except the one hot wire to the fan... no relays, etc to mess with. Not bad for $80.
Make sure you havent lost your ground. I have found a rusty ground to be be the culprit a number of times on electric fans.
Johnygee- tested the relay and it is good,thanks for that video btw it was a big help.b-blue the fan spins freely so I don't think it's that,ffr- I am gonna start at the back of the fuse panel and start looking for lose/broken wire but at the moment I can't f#+ing get the mini fuse panel off it's base,fml .pretty sure I'm just being retarded,better get more beer! Crash - thanks for the awesome advice,like I said the fan was on the car and besides I like and it's my car so I'll stick with it thanks,Blake- I'm gonna look into that controller ,thank you
I would add alot of electrical problems turn out to be a bad ground. I have had a handfull of cars come in the shop for a new fan and it ends up being a bad ground. Alot of people run a self taping screw into a fender panel for this critical connection. Screws will loosen over time.
Start at the fan itself. Unplug it right where it goes into your harness and put 12 volts and a ground to the two wires coming out of the fan. If it runs the fan is good and you can start working back from there. Plug the fan back in and trace the wires from it to your relay. Find the one that feeds power directly to the wire running forward to the fan and put 12 volts to it. If it runs your wiring going forward is ok and so is your ground. If it doesn't run first find out where the fan grounds and make sure that it is a good ground. Next, disconnect the hot wire that comes from your switch to the relay and put 12 volts to it. If the fan runs the relay is ok. The only thing left is your dash switch so just use a test light to make sure juice is going to it and out of it. IMO a 30 amp relay might be too light, depending on your fan brand. I run a big SPAL fan and use a 40 amp relay. I had my electric fuel pump stop working one time and it was one of those little flag terminals on the relay not making contact. If I pulled the terminal to on side the pump would work, but if I moved it the other way it stopped. Fixing electrical issues is a matter of process of elimination. Just find out where you are losing power or your ground and that will be what it takes to fix it. Don
I do concur! Also check continuity at ur fuse. I had a fuse 1 time barely blown and the bumpy ride kept it going off and on.
Just a thought once you fix it, most electric fans are set up to run off a thermostatic switch, is your fan and relay rated to run continuously? My electric fans never come on unless I am sitting in traffic, seems like a lot of wear and tear to run them continuously.
Check the fan motor to see if it is dragging. Use an amp clamp on a meter to see how many amps it is pulling. I had one that was pulling 28 amps, still ran but after a short while it would pop fuses and burn relays. I replaced the motor and have not had a problem since.
So this morning I tracked down the ground from the fan motor to the frame and the ground from the switch, cleaned both grounds put it back together and it appears to be working, the weird part is that I had what's labeled as the horn relay out of the panel cuse I only have one good relay and it wasn't working,switches spots and it works so obviously the fan is wired to the horn relay. Now I'm confused :-/
The Jalopy Journal
