Anybody Make the Ramchargers Fans Adapter?

mgmshar

Active Member
Joined
Feb 20, 2002
Does anybody still make the plug-and-play adapter that connects the stock 3-wire fan connector from the engine harness to the Ramchargers fans? These adapters were very popular when the Ramchargers fans first became popular, but now it seems like nobody has them.

Yes, I know the Casper's style harness with new relays is better. However, I want to old-style adapter to do something a little different.

Also, does anybody know for sure what the connector on the Ramchargers fans is? 4-pin "Weatherpak", or something else?

Thanks,
 
Caspers used to make them for Ramchargers. They used the Intrepid fan (incorrectly called the Ramchargers fan) which used a four way proprietary Dodge style connector. The simple tree adapter where one relay ran both fans was not a good choice; factory relays and wiring routinely burned up. Those dual fans have two speeds, so you would need to address that.

Eventually Ramchargers saw the light and took Caspers advice on using a relay harness instead of the adapter. The "Y" adapter is long gone.
 
Thanks John.

Here is what I'm thinking. Each fan motor has a yellow wire, a green wire, and a black wire going to it. The green wires from both motors appear to go to one terminal on the connector. The yellow wires from both motors appear to go to one terminal on the connector. And, the black wries from each motor go to the final two terminals on the connector. I am assuming that if only the green wires are energized, the fans will only run at low speed. If both the green and yellow wires are energized, then the fans will run at high speed. The black wires would of course need to be grounded.

I am thinking that if I make-up a harness that connects the output of the low-speed relay to the green wires only, the fans will turn-on at low speed. If I then connect the output of the high-speed relay to the yellow wires only, then the fans will go to high-speed (assuming the green wires are still energized). The idea is when my ECU is commanding low-fan, the fans will actually only run at low speed. If any additional thing triggers the high-speed relay (be it the A/C high pressure switch or the coolant temp. switch), the fans will go to high speed (since, presumably, the low-speed relay will already be energized).

So, I want to make an adapter that connects the low-speed relay output to the green wires on the fan, the high-speed relay output to the yellow wires on the fan, and the ground wires to the black wires on the fan. I think I could do this by modifying an old "Ramchargers fan adapter", if I can find one.

Is my thinking correct?

Thanks,
 
Sort of. The factory relays and wiring were designed to run the single OE fan, not dual fans. If you do not isolate the load from the original wiring with another set of relays, it could melt. It happened to several people who were running the basic Y adapter that used to be available (which is why it's no longer available). You will need to do the same thing that I plan to do, use the original low speed fan wire off the car to trigger a new relay fed with thicker wire and run the low speed fan wires off that relay. Then do the same thing with the high speed fans. When you are done with that you should put a different temp. switch in the intake to trigger the high speed fans at a lower temp., otherwise they won't run on high speed unless a/c is on or it's well over 200 degrees. Caspers makes great stuff but their kit just runs them on high all the time :( .

I wouldn't trust the factory ground anymore either.

EDIT: Upon re-reading the thread, I noticed that the old ramchargers adapter probably ran them on high off of the low speed relay only. The original wiring MIGHT handle both fans if both OE relays are used, but I won't be the first to test it.
 
Thanks John.

Here is what I'm thinking. Each fan motor has a yellow wire, a green wire, and a black wire going to it. The green wires from both motors appear to go to one terminal on the connector. The yellow wires from both motors appear to go to one terminal on the connector. And, the black wries from each motor go to the final two terminals on the connector. I am assuming that if only the green wires are energized, the fans will only run at low speed. If both the green and yellow wires are energized, then the fans will run at high speed. The black wires would of course need to be grounded.

I am thinking that if I make-up a harness that connects the output of the low-speed relay to the green wires only, the fans will turn-on at low speed. If I then connect the output of the high-speed relay to the yellow wires only, then the fans will go to high-speed (assuming the green wires are still energized). The idea is when my ECU is commanding low-fan, the fans will actually only run at low speed. If any additional thing triggers the high-speed relay (be it the A/C high pressure switch or the coolant temp. switch), the fans will go to high speed (since, presumably, the low-speed relay will already be energized).

So, I want to make an adapter that connects the low-speed relay output to the green wires on the fan, the high-speed relay output to the yellow wires on the fan, and the ground wires to the black wires on the fan. I think I could do this by modifying an old "Ramchargers fan adapter", if I can find one.

Is my thinking correct?

Thanks,

Problem is, the two fans on low don't exhibit enough flow CFM to equal the OEM fan on low. But on high, they exceed the OEM CFM on high speed. That's why we chose to run both fans on high. You need relays to power each fan. One relay (factory relay) can't drive two fans on high - that's where the Ramchargers design goes wrong.
 
Actually, I've been running the old adapter since about 2003. Haven't melted anything yet, although it's obviously not ideal. I wanted to get a second one to modify. And yes, with the old adapter, the fans run on High whenever either relay (high speed or low speed) is energized. I've been wanting to modify this setup to do one of the following...

1. Run only one of the fans at high speed when the low relay is energized, then run both fans at high speed when the high relay is energized.

2. Run both fans at low speed when the low relay is energized, and run both fans at high speed when the high relay is energized.

Actually, isn't Option 2 above exactly what was done in the 1999 Dodge Intrepid, where these fans originally came from? Did that car have super-duper relays and wiring or something?

If I wanted to take the time, how hard would it be to re-configure the modern Caspers harness to do either of the above?

With my FMIC, my fans cycle on and off even on a 50 degree day. However, there is no need for them to come on full blast - low speed or one fan would be enough to cycle the temp. back down on a cool day.

Thoughts?
 
What I CAN tell you is that option 2 is what dodge did on the 98-newer intrepids. And they didnt use super duper wiring, though it WAS designed specifically for 2 fans. I don't know the exact config of the harness so I can't help you with modifying one, though I plan to keep high/low operation just like stock. I need to start digging for a temp switch that kicks on well under 200 degrees for the high fan. It's interesting to hear that the dual fans on low pull less cfm than the single fan on low. I think high speed all the time is unnecessary regardless.
 
I believe that some of the premature failures with RC fans has to do with running them on high speed all the time. I could be wrong, but it sure seems odd to see so many bearing failures on those dual fans.

They do move some air on high though.
 
John what would it cost to have you build a fan harness that retains stock hi/low operation? I plan to do my own ('cause I gots mad skillz yo!) but would be interested to hear what you'd charge to do it.
 
John what would it cost to have you build a fan harness that retains stock hi/low operation? I plan to do my own ('cause I gots mad skillz yo!) but would be interested to hear what you'd charge to do it.

X2. And, if I order it on Cyber-Monday, do I still get the discount? (Gosh, we can be so greedy sometimes...).
 
I need to start digging for a temp switch that kicks on well under 200 degrees for the high fan.

If you do find such a swtich, please post back! Like you, I would like my coolant temperature switch to turn the high fans on at a low value, like in the 185 to 190 range. If I find one, I will do the same.
 
If you do find such a swtich, please post back! Like you, I would like my coolant temperature switch to turn the high fans on at a low value, like in the 185 to 190 range. If I find one, I will do the same.
What is wrong with the factory sensor/switch? My thermostat opens at 212, then the fans/thermostat maintain the temp at 185 (I have a 185 thermostat). Seems like you are trying to fix a problem that doesn't exist.
 
What is wrong with the factory sensor/switch? My thermostat opens at 212, then the fans/thermostat maintain the temp at 185 (I have a 185 thermostat). Seems like you are trying to fix a problem that doesn't exist.

I think you mistyped something. Your temp switch opens at 212?

I run a 160 degeree thermostat, I'd like the high fans to start doing their job before it runs away to 210 on hot days. On cool days, however, there's no need to bog the electrical system with both fans kicking on high instantly.
 
I think you mistyped something. Your temp switch opens at 212?

I run a 160 degeree thermostat, I'd like the high fans to start doing their job before it runs away to 210 on hot days. On cool days, however, there's no need to bog the electrical system with both fans kicking on high instantly.
I'm not sure if the fan was on at 212 (it probably was) but the temp on my scan tool got to 212, then I guess the thermostat opened and everything stayed at 185. This was idling in my garage. Stock fan and wiring harness.
 
I'm not sure if the fan was on at 212 (it probably was) but the temp on my scan tool got to 212, then I guess the thermostat opened and everything stayed at 185. This was idling in my garage. Stock fan and wiring harness.

Ummm, even the factory thermostat opened at 195 (Fahrenheit). If your temp is getting up to 212 before the thermostat opens, something else is wrong. Maybe your thermostat is sticking, or your temperature sensor is off.

Not sure if you run a front-mount, but those of us who do have a unique set of cooling problems.

I have a 160 degree thermostat, and I have my chip set to turn the fans on "low" at 176 and off again at 171. Even on a 50 degree day, while I'm driving, my coolant temp will cycle between 176 and 171 as the fans turn on-and-off. Read: There is not enough air flow going through my radiator to keep the coolant temperature down, so the fans must run to do the job, even when I'm just cruising down the highway at 60 mph. Since my "Ramcharger" fans are wired the same way everyone else does, they go to "high" speed when the ECU energizes the low-speed solenoid. This means the wear-and-tear on the fans and electrical system is full-blast whenever the fans are running.

I'm pretty convinced that on that same 50-degree day, the fans could come on "low" and still keep the coolant temp below my 176 set-point. So, the fans would only have to run on "low" on cool days, and the temp would probably still cycle between 176 and 171. On a hot day, I would like the fans to come on "high" when the temp gets well above 176 (say 185 or so). If I had a coolant temperature switch that was set at 185 along with the correct wiring, I can easily do all of the above - low-speed fans when the coolant temp reaches 176, and high speed fans when the temp reaches 185. This is the same as what the factory did, except my turn-on temperature for low and high speed would be lower.

Note: There is nothing necessarily wrong with running this engine at 212 or even higher. However, I believe that the factory coolant tempeature swtich is set for something like 228. That's a lot higher than I want to be. Higher coolant temps mean higher cylinder head and intake manifold temps, which contribute to knock on hot days. This is no good when running higher than stock boost levels on gasoline only.
 
My gm service manual lists the high speed fan temp switch at 225 and the switch for the idiot light on the dash to come on at 250 if I recall correctly. I MIGHT disconnect the idiot light wire at the manifold and tap it into the high fan temp switch to remind me to watch the temp gauge when the fans kick on high. In order to do this, however, I will need to wire in a diode so that the idiot light does not come on everytime the a/c is on (fans come on high when a/c is requested and it will back feed.) If I put the diode in AFTER the temp switch but BEFORE the a/c switch wiring taps into the circuit, I believe it will work. :) Jegs and summit sell universal temp switches at about any temp you can imagine, but they're kinda pricey, $30-40 IIRC. Wish I could find a $10 factory style switch from some other application. I'm cheap and I know it...
 
Top