- Joined
- Mar 3, 2015
- Threads
- 68
- Messages
- 380
- Location
- Lonely Nevada
- Website
- www.willenosphotography.com
As some of you might remember I purchased and installed a Ron Davis radiator in the fall of last year. Absolutely no complaints as it has provided a substantial coolant temperature drop. I love the radiator.. the quality.. the incredible welds.. the fit.. and the function. I still believe it is an "exquisite work of art". At 85º ambient.. I can drive for about 20 minutes before the thermostat opens. The A/C is not on tho. However I have not been a fanboy of the wiring harness for the SPAL fans that go along with that spec'd part of whole radiator package. In my humble opinion.. I think Ron Davis needs stick with what he is best at.. beautiful radiators.. shrouds and support hardware. Leave the electrics to someone else!
Initially I had to upgrade the mini fuses that are internal to the potentially waterproof GEP housing (relays, fuses, diode and wire connections). As a refresher to the thread that I posted about the failed mini fuses.. I created an external harness with 40amp ATC fuses to replace the suspect mini 40's which are unobtanium and don't last. I believed that the mini 40 amp fuses were incapable of handling the load from the fans.. especially at start up. After I eliminated them and replaced the circuit with 40amp ATC's.. the blown fuse problem went away and has stayed away for 6 months.
Now for the other part of the harness and hardware that I am not enthralled with. The SPAL Thermostatic Switch. Turned on at 185º and off at 165º. Well with type of temp range.. no matter how cold the ambient air.. the fans will always turn on and not shut off until you shut the ignition key off. Fan cooling this past winter was way more than needed. In fact I removed one of the 40amp fuses as I felt that oil temp stayed way too cool.. evidenced by my oil usage between 5k oil changes. Lots of overly high pressure oil due to temperature being pushed past sealing surfaces at normal RPM levels.
With a little bit of research I found that Painless Performance had a nice range of Thermostatic switches. Only problem they are spec'd to switch a ground. In the Ron Davis harness configuration.. the switch would be turning the relay positive coil wire off and on. Obviously a low amperage draw across the switch. Called Painless tech support and asked if the switch would work in that configuration. A solid definitely! Ordered up the #30113.. on at 205 / off at 190º. Perfect. The fitting for the SPAL is 3/8" NPT.. this switch is 12mm x 1.5. Located a 3/8" to 12mm adapter bushing and installed away. The bad news.. the switch only lasted about 3 weeks. Crap! Called Painless and they offered no help with a replacement.
I do believe I might have solved this Thermostatic switch conundrum.. finally! First off more research to hopefully find an even higher quality switch that could handle the low amperage 12vdc across "T-Switch". Absolutely no luck. So while taking a nice hot shower a couple of days later (great time to solve problems) I landed on what might be the solution.. short of going back to an OEM setup for fan duties. What if I got another Painless switch as they are of a high quality.. at least Painless has always had that type of reputation. Except this time not running 12vdc thru the switch.. but change it over to handle the other side of the relay coil.. aka the ground.
Had to strip down part of the harness and reconfigure it. Well.. how did it turn out? Works very well and now actually operates closer to spec'd temperatures. Before it worked good.. but not at temps that were more akin to the labeling. The great "lemonade" part of this whole procedure.. I had to drain the coolant in order to remove the SPAL switch. Was very easy with 4Runner style block drain that @NLXTACY at Wit's End sells. Bucket under the drain hose that runs down from the block drain. With a 10mm socket from the wheel well.. open the drain.. no muss.. no fuss. Put new coolant back in as I ran it all winter and spring and I wanted to make sure any contaminants flushed out. When I had to drain again to install the second switch.. sure was a SUPER easy drain / refill with the almost brand new coolant.
Would buy another Ron Davis radiator tomorrow.. just not the electric fan harness!
Initially I had to upgrade the mini fuses that are internal to the potentially waterproof GEP housing (relays, fuses, diode and wire connections). As a refresher to the thread that I posted about the failed mini fuses.. I created an external harness with 40amp ATC fuses to replace the suspect mini 40's which are unobtanium and don't last. I believed that the mini 40 amp fuses were incapable of handling the load from the fans.. especially at start up. After I eliminated them and replaced the circuit with 40amp ATC's.. the blown fuse problem went away and has stayed away for 6 months.
Now for the other part of the harness and hardware that I am not enthralled with. The SPAL Thermostatic Switch. Turned on at 185º and off at 165º. Well with type of temp range.. no matter how cold the ambient air.. the fans will always turn on and not shut off until you shut the ignition key off. Fan cooling this past winter was way more than needed. In fact I removed one of the 40amp fuses as I felt that oil temp stayed way too cool.. evidenced by my oil usage between 5k oil changes. Lots of overly high pressure oil due to temperature being pushed past sealing surfaces at normal RPM levels.
With a little bit of research I found that Painless Performance had a nice range of Thermostatic switches. Only problem they are spec'd to switch a ground. In the Ron Davis harness configuration.. the switch would be turning the relay positive coil wire off and on. Obviously a low amperage draw across the switch. Called Painless tech support and asked if the switch would work in that configuration. A solid definitely! Ordered up the #30113.. on at 205 / off at 190º. Perfect. The fitting for the SPAL is 3/8" NPT.. this switch is 12mm x 1.5. Located a 3/8" to 12mm adapter bushing and installed away. The bad news.. the switch only lasted about 3 weeks. Crap! Called Painless and they offered no help with a replacement.
I do believe I might have solved this Thermostatic switch conundrum.. finally! First off more research to hopefully find an even higher quality switch that could handle the low amperage 12vdc across "T-Switch". Absolutely no luck. So while taking a nice hot shower a couple of days later (great time to solve problems) I landed on what might be the solution.. short of going back to an OEM setup for fan duties. What if I got another Painless switch as they are of a high quality.. at least Painless has always had that type of reputation. Except this time not running 12vdc thru the switch.. but change it over to handle the other side of the relay coil.. aka the ground.
Had to strip down part of the harness and reconfigure it. Well.. how did it turn out? Works very well and now actually operates closer to spec'd temperatures. Before it worked good.. but not at temps that were more akin to the labeling. The great "lemonade" part of this whole procedure.. I had to drain the coolant in order to remove the SPAL switch. Was very easy with 4Runner style block drain that @NLXTACY at Wit's End sells. Bucket under the drain hose that runs down from the block drain. With a 10mm socket from the wheel well.. open the drain.. no muss.. no fuss. Put new coolant back in as I ran it all winter and spring and I wanted to make sure any contaminants flushed out. When I had to drain again to install the second switch.. sure was a SUPER easy drain / refill with the almost brand new coolant.
Would buy another Ron Davis radiator tomorrow.. just not the electric fan harness!
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