Ritzy4Runner

iTrader: (1)

This is primarily for those who have done the Taurus or electric fan mod. I know the probe is supposed to be inserted in the radiator fins just below the out let of the radiator on its way back to the engine. I have slightly enlarged the space between the fins and inserted the probe about 1/2 way into the fins so that I have equal amount of probe sticking through both sides. Here in is my question....

What did you use to hold the probe inplace so it does not fall out? Not too sure what would be the best solution that would not damage or cause a problem to the probe or radiator. I had a couple of ideas but do not know the validity of each or the hazard of each. A few that came to mind were, silicon AVT adhesive/sealant, JB weld, plumbers putty or some sort of putty other then plumbers that can withstand heat and vibration.

The biggest issue I can see is inhibiting the transfer of heat from the fins to the probe. I need a strong adhesive that will also allow for future removal without destroying the fins in the radiator while at the same time maintaining good thermal transfer of heat to the probe to sense correct temperature. So anyone with ideas and a rationale for their choice, PLEASE feel free to suggest. Its off to do the wiring!

Ritzy4Runner

iTrader: (1)

DEcided to use JB Qwik to hold the sensor. Got the system all wired up except for one wire and that is the auto fan when the A/C is switched on. I don't know where to find the wire for the A/C compressor clutch so until I figure out where it is, I have the wire coiled up and secured.

I did a check test on the setting for the thermostat. My engine got up to operating temp, the thermostat opened, but still no fan came on. My temp gauge is still reading just under 1/2 which is the normal postion of the indicator. I took the truck for a drive and still no fan engagement, and still no temperature increase. I did get the high speed manual over ride working and I can shift over to HI with just a flick of the switch. I really didn't seen any change in the temp gauge either when I engaged the HI speed fan. Will have to keep checking and testing. May take a drive over to Toyota tomorrow and let the techs over there shoot it with their temp gun to see what the operating temp is. I'm just wanting to know if I have the thing hooked up right and the sensor is working correctly, oh well at least in an emergency I do have a fan to cool the radiator. any suggestions?

hiloracerboy84

what kinda controller are you using? my dcc probe is just stuck between my finds without anything to hold it there. the metal is soft enough that i just shoved it in and left it. ive done probably over a hundred miles offroad with it, lots of it on washboard gravel stuff at 10-15 mph, and its still sitting there fine. my dcc came stock at 195 i believe...not sure though, and it usually only kicks on when im sitting at lights for a while. if i start the truck and let it idle to little below half on the temp gauge, itll take quite a while more before the fan kicks in. assuming from the hi/low deal u have going on, im gonna say you have something other than a dcc. with the ac deal, the pump is the furthest thing to the left on the passenger side of the block (i think). theres just one wire coming out of it thats plugged into it with a connector thing. all i did was strip a little of the wire away with a blade, strip about an inch of wire from the one connecting to the controller, and wrapped it around a till the tag end ran out. no need for a really good connection. as long as it gets the input, itll kick the fan on. wrap it up w/ some electrical tape and you should be good to go. g/l

mt_goat

X2, it depends on the probe. The DCC probe is very low mass and has a special heat conforming rubber around it to help it stay in place.

So, what kind of probe you got?

I'm using another probe from a cheap controller for my trans cooler that I used heat resistant black RTV along with zip ties to hold it in place. I placed the probe on the cooler with zip ties (metal to metal contact) and then covered the probe with the RTV. Then I set the temp that the fan comes on. The RTV did seem to stop the heat from getting to the probe

mt_goat

Below the outlet of the rad? The outlet of the rad is at the bottom, its pretty hard to get below that. Do you mean below the inlet to the rad?

There are 2 schools of thought on the placement of the probe. One says put it near the inlet of the rad to get the hottest part of the rad and respond quicker to the engine temp. The other says to put it just above the outlet of the rad, that allows the fan to shut off or slow down while the truck is running at a speed that provides enough natural air flow (if natural air flow is enough the probe will detect it). Is kind of a chicken and egg thing too...hehe. The biggest concern is which spot you have enough temp adjustment range for.

I have mine (DCC controller) near the outlet of the rad (coolest part of the rad) and I have it set to come on at the lowest temp possible. Not the best combo, because the fan doesn't run as much as I think it should. I'm thinking about moving it to the inlet area and readjusting the temp setting. That or doing something to decrease the natural airflow around the probe spot.
The red circle shows where mine is now:

As you can see I have a lot of natural air flow in that area.

Ritzy4Runner

iTrader: (1)

Thanks for the input. I am using two controllers, one is adjustable the other fixed. The adjustable is for the normal low speed setting and the fixed is for the high speed over ride. Both are made by TorqFlo and were available at Auto Zone $34 varible/$24 fixed temp.

If you are interested the part numbers are:
733647 - Adjustable Thermostat
733652 Single stage Thermostat

I was concerned about the probe moving around as the install instructions cautioned that the probe must not be inserted past the thickness of the radiator. I was looking at a mid install but with that caustion, I opted to install just till it was flush with the outer side of the fins. I inserted the probe from the engine side so the shroud protects the exposed end of the probe and wiring.

My concern yesterday was that I could nto get the adjustable thermostat which is hooked up to the slow speed of the Taurus fan to come on. Even after driving around for at least 30 minutes, the temp never raised about about 40% and Iknow the htermostat opened as the hosed got hot and pressure was evident. The radiator core was hot as well. I just am concerned about the thermostat being connected correctly. Will have to study this further today.

I still can not visualize where you took your pick off for the A/C compressor. Once I find the wire I need and how to get at it, I can do what ever I need to do to ensure a solid factory install. Thanks again for your input.

Ritzy4Runner

iTrader: (1)

Thanks Dale, I have mine at the top of the radiator. That hose began to heat up near the engine side long before the lower hose. I know the thermostat is working on the engine as it opened and the hose and radiaator became quite hot, but still well within the normal operating range. Like I said, the engine temp did not climb above the normal operating zone. I'm going to take the truck to toyota this afternoon to confirm the engine/radiator temperature then maybe try to adjust the control temp to see if it kicks on. if not then I must have a wiring issue and will need to resolve that in short order.

mt_goat

I guess I missed your 2nd post in this thread.

The factory temp gauges suck, they are little more than a fancy idiot light. If you want an acturate temp reading go by the OBDII readout. Any mechanic can hook up to that and get a temp reading for you, or you can do it yourself with a laptop and the scantool (highly recommended):
http://www.urdusa.com/product_info.p...s_id=840100000

Are you saying you stuck the probe all the way through the radiator? If so that may be the problem, there is too much air flow at the edge to get the probe hot. Needs to be more in the center (thickness wise).

mt_goat

There is only one wire going to the AC compressor (can't go wrong). The compressor is grounded by bolting to the engine is the reason there is only one. You can unplug it to get better access to tap into it.



BTW you don't need or want to cut the AC wire to tap into it, just pull back the insulation without cutting the wire and wrap the tap in wire around the AC wire, then solder and wrap with tape and put a zip tie around it to hold the tape in place for a long time. Something like these taps:

Don't forget to loom all positive wires.

mastacox

The purpose of the electric fan is for it to come on only when needed, and it should be off otherwise. With that in mind, you should measure the temperature of the water going to the engine from the outlet of the radiator, because if the radiator is getting enough air flow without the fan (say like driving down the highway), it should be off. The fan should only need to come on when the temperature of the water going to the engine starts to rise, which means the radiator is not getting enough air flow.

On my 4Runner, the fan will usually come on if I stop at a stoplight after driving around some, or if the engine has been idling for a little bit. It will come on for a little bit, and then slow back down and turn off. During this whole process, the temperature gauge doesn't budge. My fan might run all of the time from 50-100% if it's a hot day in Tucson and I'm running the A/C, but on some cooler days in Los Alamos it will barely run if at all.

That is where I have mine installed too. It's the best place for the probe to be installed as long as you can adjust the activation tempertuare of the controller. If you can't adjust the activation temperature of the controller (or at least can't adjust it enough), then you have to adjust the location of the probe to find the "sweet spot" in the radiator.

mastacox

Yeah I tried to tie the "A/C Wire" on my DCC controller into a wire on my A/C condenser fan because I only want the electric fan to kick on to 50% if the condenser fan turns on, but that didn't work since the condenser fan is ground switched rather than hot switched (which meant the electric fan was always on at 50%, rather than only when needed). So I unplugged it and haven't done anything else with it since, because it turns out everything works fine as-is, and my A/C blows ice cold in the summer time (when my R-12 is full anyway...)

mt_goat

Well said Brian

Ritzy4Runner

iTrader: (1)

Good info and thanks for the pic. (LOL was hoping you would clarify did not want to have to pull my engine like in the pic!) It should be fun getting to that wire from the top of the motor

Totally understand the issue about the purpose, was the biggest reason I installed this mod. My only concern is that it is correctly installed. I tested the manual over ride and it works just like its supposed to which made me VERY happy:

I still have to connect the A/C control wire and if I get that hooked up I can test the fan ops that way too. I tied several lines together to minimize wire runs. For example I have the same power supply wire from my Aux fuse panel tied to both power inputs to the seperate relays that control the fan speeds. I used the 3 position rear heater switch (modified) so that they can not both be on at the same time, letting me use the power wire for high speed as well as for low speed. The two seperate ground wires from the relays ended up being the same grounding loop mounted to the fender well that holds one of the relays. Power for the 3 position switch to turn on the relays were two seperate wires connected together to use the same aux fuse panel location.

This is great input guys and THANKS, I guess everyone is gone on the weekends! LOL, I was needing some input and posted a few quick notes but hey better late then never!

mt_goat

It's really easy, just get a hoist and lift up the engine and the wire is right there, hehe.

Ritzy4Runner

iTrader: (1)

Ohhhhhhh well why didn't you say so! Heck I'll do that during my lunch hour!

You're killin me Dale, you're killin me!!

Ritzy4Runner

iTrader: (1)

Took the truck over to Toyota and asked if they could get one of the techs to use their infra red temp scanner. The truck was fully warmed up and when the tech took a shot of the radiator it only showed 137 degrees and then got a check of the core fins in about the middle of the radiator and it showed 142 degrees. The electric fan controller thermostat is supposed to be factory set for 165 degrees so that would explain the why it still had not come on. I guess with a clean cooling system and new radiator using that red Toyota coolant it does run a bit cooler. I had the guy check temperature drop on manual HI operation. When I flipped the switch to HI, it took about 10 seconds and the temp started dropping. I went to 136 in under 15 seconds so I am pleased so far. I may try to take a road trip to eastern Washington late May early June and see what happens. Don't need any issues in the valley in California in August! Thanks for the input guys. I have started the install thread if you care to check it out. I have been putting it up in parts. First two are posted.

mastacox

I would make sure and carry extra relays and fuses for emergency situations.

When I first installed my electric fan I installed it with a 2PDT switch and two 30 amp relays, one for hi and one for lo speed on the fan. Well running in the dunes the fan's hi setting melted the relay, causing the fan to turn off (which I didn't notice right away) and the 4runner overheated. Fortunately I was able to borrow a 40 amp relay for it and everything worked fine until I got the DCC controller.

Moral of the story, carry an complete "backup electrical system" for the fan until you consider the installed system "proven," and maybe even after. That way, if what you have fails, you will at least have a way to "hotwire" the fan to make sure it runs no matter what! I carry the old switch and relay with some wire, just in case something happens and I have to jury-rig a different electrical path to the fan.

aviator

you don't need to try to get at that wire AC from the top, just drop the front skid plate and you'll have all the access you need from down below. lol

mt_goat

Good points Brian. My fan has a complete backup system in place, all I have to do is flip a switch and the low speed side is "on" all the time via a 40 amp relay. The same switch (on off on) turns off the DCC controller on the high speed side or turns both off for a deep water crossing.

mastacox

Yeah, having some redundancy in such a critical system is a must IMO.