recent issues with my Spal dual fan with programmable fan controller

[WagonCrazy]

Have had a PRC radiator setup with dual Spal fans installed and working properly on my 57 nine passenger wagon for many years now. The programmable fan controller allows you to set the low temp-Single Fan ON and the high temp-Both fans ON at the temps you want for your engine.

Mine has been working flawlessly for about 5 years now.

All of a sudden, things changed a week or two ago.

I noticed when I start the wagon, both fans are always ON....and stay ON...regardless of what the water temp is. Also, turning on the AC doesn't affect this anonmaly....they fans are always ON both of them, full speed.

So I recently went back thru the programming procedure on the controller, setting the LOW and High temps, and cannot get it to work as before. No matter the "spread" in the Low and High temp range, the controller now doesn't work correctly, and just "blinks 3 lights all the time" (indicating the temp spreads are not wide enough). I've tried several times at reprogramming the controller, each time with wider temp spreads, and it will not work.

So I'm going for the lesser expensive part in this equation...the temp sending unit in the drivers head. This is where I've had the sender all along, and it's a 2 wire late model style, that drives the Spal controller and also the stock dash gauge. It's about a $35 part from Napa, and I'll know later today if that worked.

if not, then the controller is probably shot. (If that's the case, then this will be the 3rd Spal controller in the 10 years since I've owned this wagon. The first one died after 2 years due to water getting inside it. This one the second one, is mounted in a dry location in the engine compartment)

On top of all of this, I noticed the PRC aluminum radiator has sprung a leak. PRC welds their radiators to the cross bar, so pulling that to get it fixed will be a bigger job than it needs to be. Aargh...

[chevynut]

Paul, if the controller is telling you that the spread is not wide enough, and won't let you even program it, why would you think the problem is the sender? Sounds like your controller is bad to me.

I am using the Dakota Digital fan controller with relays to run the fans in series on the first setpoint, and in parallel on the high setpoint. It also has AC inputs. I haven't used it yet but I have heard of several guys doing this with no problems. Just in case you want to try a different solution.

[Maddog]

The controller is at fault. Did it get wet recently? It goes crazy if you get it wet.

[WagonCrazy]

Called Spal tech support today, to learn they discontinued ALL forms of fan contollers many years ago. They dont have anything to replace this with. They emailed me a schematic to wire up the fans using the relays directly, and a thermostat that triggers it when it hits a certain temp. All the way on, or all the way off.
This would have been the 3rd controller I had in 10 years, so they basically came to the conclusion that their product (all 3 generations of it) were a POS.

Ho hum...

[WagonCrazy]

Maddog. I don't believe the controller got wet at all. Not where it was mounted. Heck we don't even get rain here anymore...so it's just the 3x per year car wash with the hose and even then, I have it mounted up on top of the inner fender, away from all sources of water intrusion. I just think their product was not all that good (from a longevity standpoint) and it's showing...

[Rick_L]

A telling deal for them to tell you to wire it up with switches instead of sensors.

I've never heard anything bad about the DD product. Or better yet you can use an OEM EFI computer or an aftermarket one like the Holley. Those work quite well.

[WagonCrazy]

Or better yet you can use an OEM EFI computer or an aftermarket one like the Holley.

I don't have any aftermarket OEF EFI controller on this wagon...it's just a carbureted SBC. I've been looking at the DD and a Painless F-5 controller. The DD seems cheaper and easier to deal with, and I may be able to use my existing Spal relays and sending unit...

I hate replacing equipment a few years after I've spent good money and effort on it. Frustrating to say the least. Get over it Paul and move on. :(

[Maddog]

My controller was on the inner fender and got wet when I washed the car, went crazy got it dried out and it worked again but it was never worth it. Use the relay kit with temp sender, off or on is all ,that is needed. Trying to stage 2 fans in a warm climate is a waste of time. the engine will go from your low point to the high point in a matter of minutes so what's the point? I had mine set for first fan on at 115, second at 160 there was only a brief lapse between the two, no reason to bother. One 12" fan is not enough air flow to keep it at the low setting. I'm glad to hear they discontinued a waste of money product.

[chevynut]

IMO while the PWM fan controllers are nice, they seem to be inherently more complex and more prone to failure. I like the 2 setpoint design of the DD PA-2700. You can run the fans at 50% and if that's not enough they kick up to 100%...it doesn't need to be more complicated than that, imo. Also, the Painless F5 controller is rated for two 35A fans which is about where the Spal fans operate at full speed. If you use your own relays you can use the 70A ones for better reliability.

[WagonCrazy]

Spent the afternoon yesterday under the hood. Unwrapped all the wiring cover to find 2 issues. The thermostat connector to the PWM controller was unplugged. The tab on the weatherpak connector had broken allowing the 2 ends to seperate just enough. Second issue was one of the Spal fan connector plugs was failing, allowing arcing of current intermittently. Fan on intermittantly.

So it rewired both with new connectors, hooked it all up, installed the new thermostat and fired it up and it seems to be working now. So the controller is no longer suspect. But when i turn the AC on, its not firing up the fans (regardless of the temp). So theres a little more troubleshooting to do still.

Wiring gremlins...operator error too. :(