DC Control 3018 kit problems

[Marty G Cars]

Being a novice, I thought that buying the DCC 3018 Mark VIII fan/controller kit for my 68 Camaro would be the simple route to go. Well I have everything installed and the fan works, but it doesn't seem to be pushing anywhere near 4300 cfm and no matter where I turn the variable temperature setting knob, the fan comes on when I turn the ignition key on.

I followed the directions except I could not see why it would matter on the battery positive connection, so I DID connect it to my starter where my battery cable attaches. The yellow ignition wire was connected to a 12v ignition switched source from my AAW harness. The blue AC wire was connected to my AC compressor input wire. The battery negative wire was run to a chassis ground. The probe was placed on the outlet side of the radiator as specified in the instructions. I am running a 180 thermostat.

The problems are -
1) Always on when ignition is on no matter if engine is warmed up or not
2) Doesn't seem to blow 4300 cfm
3) Temp guage reads 180-200, but I haven't even run the motor hard yet (under 4000 rpm) and I think it will run much hotter when the summer heat builds and I start running the AC

I hope this is enough info to enable someone to figure out what is going on.

Thanks!
Marty

[baskin]

This is a pretty easy one, if you have the yellow ignition wire connected, it's suppose to run at 10% when the ignition is on. The filter needs to be run for a couple of reasons, but one of them is that a run that far to the battery http://www.dccontrol.com/componentsR1.htm http://www.dccontrol.com/faq.htm#batt causes the controller short circuit protection to kick in and limit the controller output. (I'm assuming that the fan speed does increase when the knob is turned ccw)

[Marty G Cars]

The fan speed never changes no matter where the temp control knob is positioned. I have had other elec fans that had a speed control knob, but it seems as though this knob is just for setting the temp point where the fan starts coming on, not to adjust the speed of the fan (I think).

Do you mean that with the yellow wire connected to a switched ignition source, the fan will always be limited to run at 10% maximum power? I'm new to this wiring stuff, but why would that be the design? Should I just disconnect the yellow ignition wire altogether?

[andrewb70]

Disconnect the yellow wire. Its for the AC. So when the AC kicks on the fan will stay on as long as the AC is on and run at 10%.

Andrew

[Marty G Cars]

Let me see if I understand this - when the blue wire that is connected to my AC compressor senses that the compressor has kicked on, then the yellow switched wire signals the fan to come on and run @ 10% power to cool the system that now has added heat to be removed? Obviously I'm not the smartest car guy but that seems to be a wierd design.

Later today I will be driving the car and I'll keep it set up as is, when I get to my destination (about 30 min drive), I'll leave the car running, pop the hood, disconnect the yellow wire and see what happens. I have disconnected the yellow wire before with the car cold and just sitting in my garage to see what happens and with it disconnected, when I turn the ignition on the fan does not come on. I am a little nervous about pulling the yellow wire and just taking the car for a spin to see if my new motor over heats.

Please excuse my inexperience.

[baskin]

No, The AC input sets the minimum speed to 50%, if the car gets hotter, the speed will raise, The yellow wire sets the minimum speed to 10% , if the car gets hotter, the speed will raise, if both are high, the fan will run at 100%.

Did you read the links that I posted?

[Marty G Cars]

baskin - thanks, I did read the links and had seen the filter option with my paperwork but wasn't quite sure if it was needed.

So bear with me in my understanding - Get the filter and connect between my positive battery cable at the starter and where I ran the positive wire from the fan.

When my ignition is on (with the yellow wire hooked up) the fan will always run at a minimum of 10% power and increase (power, thus speed) when the input probe senses an increase in temperature.

When the AC compressor kicks on the fan will run at a minimum of 50% power and increase (power, thus speed) when the input probe senses an increase in temperature.

Did I pass?

[baskin]

Yes, except the input filter drops right across the input terminals of the controller on the fan

[Marty G Cars]

Ok, I am going to order the filter (part # 1.5KS) and attach it between the ground and positive terminals on my 3018 model, correct?