How do you wire up an Electric Temp gauge to a C4? Where do you put the sender? I don't know were to begin so pics will help also if you have some. Thanks
The best way is to pull the pan and get a pipe fitting the size of your sender, drill a hole in the side of the pan and weld the fitting in the hole. Screw your sender into the fitting and then wire it to your guage. while you have the pan off drill a hole in the bottom corner of the pan. Cut a fitting off so that you only have a small amount sticking through and a small amount sticking out and weld this into the hole. Find a plug and screw it into the fitting. Then the next time you change the trans. oil and filter you can drain the oil before you take the pan off.
Thanks Ronald, I guess I'm headed back to the welding shop. Welding is another one of those things I have got to learn how to do.
The pan is not the best place to install the temp sender. Consider the correct 'tee' block and install it in the hot output line (close to the trans) going to the radiator. This point measures the hottest temp the converter fluid shearing generates. In a c4, the converter shears the fluid full time even above the min converter slip point, unlike an overdrive with full lockup. Looking at the temp level after the fact does not tell you what is coming out of the trans. Depending on how much cooling is in the return line, you can cool the fluid below the pan temp, but the actual pan temp can be higher and you have not accomplished all the cooling that you think. There is a min. point you can cool the pan too unless the pan is replaced with an alum higher capacity unit. It is subject to the operating heat radiation, conduction and even engine heat back thu the bell housing. With consideration to the break-down temp of F type fluid, you don't want to see more than about 260* coming out of the convertor on any regular basis without changing the fluid more often. In cases where there is either a blend or full synthetic fluid used, the max break-down temp is higher for a greater margin of safety. There is more to this than most think. All the charts and info say this and that but never tell where or how they measured temps they give. My experience for the above comments stems from doing aux cooling installation, measuring temps with an infa-red heat gun at various points in the cooling circuit, using syn-blend fluid and pulling combined weights over 12,000 lbs thru an 4r70w automatic. Having the sensor in the cooling output line shows near instant temp changes vs load changes but the temps are much higher (than in the pan) so you would have to get use to seeing those higher heat levels once it is all understood because those operateing temps are there whether you measure them at that point or not.. With the sensor in the pan, the 'average' pan temp is all you see with slow changes and remains slow to cool after the engine is shut down. Depending on the car's application, for high heat loads, consider that the cooling radiator runs at just below engine thermostat temp levels and keeps the fluid at that temp before either going to the aux cooler or going directly back to the pan. In my application using an electric gauge and sensor in the output line, no radiator cooling in the loop, two aux coolers and blend fluid, I see temps in the 250 range during out of lock running pulling hills and in lock temp below 150 in lock. Temps in non pulling application and in lockup are in the 110 range depending on the outside temp and in the 130 range depending on how much street running is below converter lockup. So there you have some info the consider about a subject that is little understood.
That helps also Bluegrass considering I can't weld. That drain plug sound good too. I guess I will have to do part of both answers.
I'm a believer in Bluegrass. Not even the BETS bullshotters can come up with some of the stuff BG does. <---N awe So, really, having a temp probe is a moot point. The best you can do is add a tranny cooler (or two) and synthetic oil?????? If so, which brand would you recommend? Thanks for the info, btw! ----------- On another note: A buddy bracket-racer of mine will not run a tranny cooler. He uses the stock cooler on the radiator. 'Claims it helps him to be more consistant.
Bluegrass is correct about putting the sender in the line. That is the best place for it. I only stated that it could be put in the pan. I don't know what you are doing with your car. I think for a street driven car with a good transmission if you put the sender in the pan and know what the temperature normaly runs and if you start to see a rise in the temp. you could determine if your tranny had a problem. Also it would be a good time to put in the drain plug. But you should really do as he says if you want an accurate reading. Also as stated you need to run a good after market cooler.
Basic street driving but not everyday use. Weekend track every so often & road courses some times. Just enjoying the car. But I do drive hard from time to time. I will be putting a cooler on it. I'm in the process of replaceing all my gauges & warning lights with real gauges. Plus adding a few other gauges like the Trans Temp.
