A bit of help, please with my ERA 427

wemooz · #1 (**permalink**) 12-19-2011, 05:24 PM

I need to replace the thermo switch that controls the electric fan on my FE powered ERA 427, since the switch seems to have died. It looks to me that it might be a challenge to get hands or tools in the right position to make this replacement. If anyone has done this and figured out the best way and the correct tools, it would help me to do the job. I am also supposing that I will need to put the car on jack stands so that I can drain the cooling system.

DonC · #2 (**permalink**) 12-19-2011, 06:24 PM

Email or call Bob Putnam or call Doug at ERA. As I recall looking at mine it shouldn't be a particular problem once you get the car up and the coolant drained.
Bob may have a procedure for testing the switch to make sure that's where the problem is before you go to the trouble of pulling it.
DonC

wemooz · #3 (**permalink**) 12-19-2011, 07:01 PM

Thanks, I used the ERA recommended procedure to test the switch and it is dead, so I need to replace it. But the location seems challenging to me,and before I start I would like to get whatever advice is out there. Bill

patrickt · #4 (**permalink**) 12-19-2011, 07:27 PM

You have two choices -- pull the hoses off each end of the bung tube and pull the tube out, or pull the hoses off the other ends and pull the whole two hose one bung tube assembly as a single unit and then pull the bung tube out while it's on your work bench. If you do that, use a Sharpie to mark the orientation of the the bung tube to the two hoses before you pull them.

patrickt · #5 (**permalink**) 12-19-2011, 07:57 PM

If you choose to pull the hoses at the bung tube, come in from the front, under the car, over the steering rack. Like this...

TButtrick · #6 (**permalink**) 12-20-2011, 05:25 AM

Can't just unscrew the switch from the bung while in place? Must be less room there than the pics would indicate.

patrickt · #7 (**permalink**) 12-20-2011, 06:05 AM

Quote:

Originally Posted by TButtrick

Can't just unscrew the switch from the bung while in place? Must be less room there than the pics would indicate.

It's in a kind of tricky place, way down low above the frame but below the X-member. What you don't want to do is damage the bung tube, if you can help it. Here's a shot of when I was replacing my balancer last year -- you can see where it is (and his could be twisted at a different angle). Coming in from the front, as per my previous post, is the preferable way, IMO, and then you can just take your time getting the switch out of the tube while you sit at a table.

flaflier · #8 (**permalink**) 12-20-2011, 07:06 AM

I just redid mine on ERA154, and I agree with Patrick, drain the coolant, disconnect the wires from the switch, and take the hoses off at the water pump and the radiator. Pull the whole thing out to the front. Mark the hoses, then take the section of pipe that has the bung out, put it in a vice to hold it, then take the switch out.. my switch was VERY stuck from having been in there for a long time. If you try and take the switch out without removing, chances are you will just flex the hoses, and bust your knuckles.

Good luck!

Jim

RallySnake · #9 (**permalink**) 12-20-2011, 10:00 PM

Wemooz,

I have to give you another option because a single switch like that just cannot handle so much current very long. It's doomed from the start.

I have used about 6 different setups in 25 years. The best setup is made with one of these: Hayden Automotive 3653 - Hayden Electric Fan Controls - Overview - SummitRacing.com and two of these: (5)12V BOSCH STYLE RELAYS 40A SPDT + (5) 5-WIRE SOCKETS | eBay

Find a small plastic box and mount the thermal switch in it with the shaft sticking out of a hole. Mount the relays in there too. (I use two for redundancy and because they're cheap and light.) Then, put a knob on it and mount the box as high as you can in the engine compartment. Very carefully unroll the copper tube and slide the probe into your radiator fins near the water outlet (you only want the fan to come on when the radiator is not cooling the water). Use plastic split wire loom to protect the copper tube like this: 100' BLACK PLASTIC SPLIT WIRE CABLE LOOM - 3/8" | eBay and use cable ties to run it along safe areas.

There are several advantages with this setup: 1. You can choose the temperature for the fan to come on (I like 200) . 2. You can connect a low current (cheap) extra switch in the dash to turn the fan on. 3. You can connect switched power so the fan goes off when you turn the engine off (prevents dead batteries). 4. If you do 2, then you can easily add a light in the dash so you know when the fan is on. 5. You don't have to remove the old switch (just pull the connectors off to connect to the new system). 6. You don't have to drain the cooling system.

This setup has worked very well for me for many years. If you have any trouble with the wiring diagram, let me know.

RS

strictlypersonl · #10 (**permalink**) 12-21-2011, 05:09 AM

That switch is only used to trigger a relay. The load on the contacts is very low.

patrickt · #11 (**permalink**) 12-21-2011, 05:31 AM

Well, with that settled, let's take a moment to revisit a wonderful ERA fan/electrical circuit thread. Cool Modification - For Pusher Fans Only, Though Of course, you have to have the pusher fans, in addition to the regular fan, to appreciate it.