ok, here is the switching circuit...... The starter switch originally had all of the current running trough it for the whole system so I re-circuited the RUN and ACC main feeds through a separate relay box which feeds the fuse panel directly. That way the switch is just turning on the 70A contact rated relays... which will let the switch last and again.... easier trouble shooting if needed since the battery is now in the back I used a 4/0 welding lead to bring the positive power to the front. I built a landing termainal and added a master disconnect switch.
here's the last of the electrical.... it's the relays that control the electic windows, door locks and LEDs. The feed for these relays come from the fuse panel to this separate relay panel. I have two relays per window (up and down) and two for the door locks (lock and unlock) which flop the polarity so I need only a switch inside to activate the appropriate relay. I also installed a toggle shut-off switch for the feed to the inside switches because there are times my dog is in the truck without me and I don't want him rolling down the windows or unlocking the doors by accident. This may sound confusing, so I have it in Autocad where I can turn on and off any circuit for easy trouble shooting. I will try to get Autocad to output a JPG of the wiring schematic so I can post a picture of it.
I have the original radiator, it was serviced and a temperature switch port hole put in the lowest section of the top tank. I installed a temp switch with a range of 160 off and 185 on. The thermostat in the engine is 180 degrees so the temperature reaches about 185 degrees then the electric fan comes on and drops to 180 where it seems to hover. I have put about 300 miles so far on the truck and this has been consistently the case.
I'm going to suggest that you change those settings -- if you have a 180 thermostat then the running motor is never likely to fall much below 180, however once on, your fan will never turn off because the running motor never falls to 165. I'd set the turn off at around 185, and the turn on at maybe 195.
He is operating the fan using radiator temp, not engine temp. Radiator temp is (well it had better be) lower than engine temp.
I don't want the running motor below 180, that's why I put a 180 thermostat in it. The fan does turn off and on, I've watched it cycle for over 300 miles now. It turns on at 185, runs the temp in the radiator down to 165 and shuts off, then the radiator temp rises to about 185, fan turns on again and runs the temp down..... and around and around we go..... all while the engine temp is running at 180 degrees.
All of the relays, brackets, fuses, housing and wires came from a salvage yard. I have found in doing auto looms, I am looking for as many different colored wires that I can get my hands on that are around 20' in length..... which is really easy to come by at a salvage yard and a whole lot cheaper than the parts store
He says the sensor is in the top tank, and that obviously means the '60 radiator is a vertical tube model. So, water in the top tank has not yet been cooled, it's straight out of the thermostat -- which presumably did not open until the water behind it got up to 180. The whole point of the engine thermostat is to hold back that coolant until the motor is up to 180. Let me see if I can explain this with an example: say you have a house with an a/c that you have set to 68F, and the house also has a furnace with a separate thermostat which is set to 72F. Both are enabled when you turn the key to enter your house on some cool morning. The a/c immediately senses that the house is below it's set point and does not turn on. The furnace sees the house is only at 60F and turns on. As the house warms past 68 degrees the a/c turns on, but the furnace has much greater btu than the a/c, so it eventually gets the house up to 72. What does the a/c do in this situation? How does it ever turn off while the furnace is keeping the house at 72? (if you don't get the analogy, the motor is the furnace, with it's thermo set to 180, and the fan is the a/c which is set to turn off at 165)
I don't have a clue as to what you are talking about, and suspect you don't either. As was explained, it works. Actually it is a common set up for electric fans. If you don't understand something, just ask. There is no need to make up wildly implausible scenarios that only serve to obfuscate.
I tried asking it simple and got stupid replies. How does the water in the top tank get down to 165, when it must be 15 above that to pass through the thermostat? Does it lose 15 degrees just from passing through the radiator hose? I suspect his thermostat is stuck open or not installed. That's the only way this could work.
Actually it loses more than 15 degrees mixing with the much cooler water in the radiator. That is why he positioned the sensor near the bottom of the upper tank. The fans on My Ranchero are set up exactly the same way, and they cycle on and off, just like his do. The thermostat regulates the engine temp, the fan controller regulates the radiator temp. I can set the radiator temp all the way down to 165 or 170 degrees, and the fans still cycle off and on, they just run longer when on. Controlling the fans with engine water jacket temp is a bad idea, as it only rises when the radiator is heat saturated. At that point one is at great risk of overheating if the engine is under severe load or on a hot day.
Right, and that's why all modern cars work from sensors in the radiator. Oh, wait, no they don't, they all use sensors in the water jacket. Enough said. Water in the upper tank of the radiator is sensibly the same temp as the water coming out of the thermostat. All of the water already in that tank also came directly from the thermostat. It only gets cooler as it passes down through those tubes with the fins toward the bottom tank. That's how radiators work.
See? You don't want to learn, you want to argue in order to defend your ignorance of why this set up works. It is true that there is more than one solution to controlling the electric fan, the one that is right, or wrong, depends on the application. Have you never encountered that idea before? I am trying to get you to understand why and how the system works. You are trying to argue that a system that works in thousands of vehicles does not. After all, the vast majority of the after market electric fan set ups use a sensor located just under the bottom of the upper tank, or near the top on a side flow. That's OK, everyone (except you) is a moron and uses the fact that the system works as evidence that it does. You, being smarter, view that the fact that the system works is irrelevant to your higher state of consciousness. Please have pity upon we poor ignorant fools trapped in reality.
I have a new thermostat in the motor and it works. With the cap off you can see the water flow increase when it opens and after the car sits and cools down below 180, you can see the water flow increase again when the temperature goes back up to 180. I just used my digital laser temp meter on everything and everything is showing the temps that are indicated.... so I don't know what else I can say. If you don't believe it works, you're welcome to come over to see it..... maybe that will work.
Caper, I want to apologize to you for taking part in running your thread off into the weeds. My original intent was to be helpful. I would say, the fact that you can see the motor thermostat opening and closing is evidence of a problem; it should never close on a warmed-up motor. Essentially you are using fuel to heat up water that was cooled too much. And it's unnecessary; with a pressure cap and coolant you wouldn't likely see boiling below maybe 250F. Can you tell me why you set the turn-off lower than the thermostat temp? What was your thinking? You have two systems fighting each other there, the motor thermo trying to keep the motor at 180 minimum, while your fan system is trying to keep the coolant at 165 maximum. Congrats on getting it to work.
BB Buy or borrow a non contact thermometer (infra red). Take it out to your car that has a standard (non electric) fan, and check out what is going on at the radiator. Once your preconceived notions are replaced by facts I suspect your mental block will disappear.
Sorry, I don't have a car with a non-electric fan. Have gone well past that 1900's design, as has the car that is the subject of this thread. How is your experiment relevant? My Chero has an electric fan with a controller of my own design, uses a standard Ford temp sensor in that extra hole in the water outlet. And it works rationally, I do not compete with the engine thermostat. I use no hysteresis other than the innate slowness of the sensor. With the car parked and idling it eventually cycles the fan on/off at about 2 - 3 minute intervals. Fan never comes on while driving the car at any speed above 20mph or so. Did you see his last note that he can see the motor thermostat opening / closing on a warmed-up motor? Think that's correct behavior?
burningbush.... What I was saying was when the motor is cold and I start it up the first time, I can see when the thermostat opens up for the first time.... which is at 180. I then turn off the motor and let it cool down for a few hours and start it up again.... I can again see the when stat open, which is at the right temp so I know the stat is working correctly. Look, the motor stays at 180, the fan turns off and on and I am in Florida where it is hot. I joined this group in hopes that what I have done might help or give someone an idea. I not here to defend my actions or to agree hypercritically when I see that it works....
