Electric Fan Swap Questions

[ratdude747]

I have a simple thermal switch on mine directly to the battery. It's big enough to handle the load of the fan directly. So if the engine is hot, it comes whether the key is on or not. Mine cycles several times on a hot summer day after I shut the vehicle down, and I have never had any problems with the battery. A lot of the older vehicles were this way, that's why they had the warning embossed in the fan shroud "Fan can start at anytime"

Duh. I remember my mom's old 1997 Nissan quest having that warning. I may make a tag with such at work; we have a 2" yellow label printer that would be perfect (I removed the red sticker from the new shroud). Thinking ahead in case for some reason somebody else is working on it... last thing I need is an insurance mess due to some twit getting his fingers nailed in the fan.

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More pics:

Prepping the fan shroud for JB weld:

Fan dropped in:

Had to do a lot of trimming to the Journey housing. The extra side cuts are to account for the "lip radius" on the sides of the ranger shroud:

After cleaning it up, I set it up and JB welded it:

Shroud top:

Shroud bottom:

(I put some in the gap before dropping in the fan, why it's so thin)

Shroud side:

(and one more side bead like above, wasn't able to shoot without disturbing the setup)

It's curing up right now... I'll add the cutout to allow fan replacement later. Used one pair of JB weld tubes.

I also swapped the water pump pulley bolts for button head screws (M8x1.25, 16mm long, available at the local Fastenal):

Progress?

 

[ratdude747]

Did a test fit this morning, fits fine. Spent the rest of the day working on a different repair .

Noticed a bulge and some cracking on the cold tank of the radiator... Looks like I better replace that! While looking up a replacement radiator, discovered that apparently they make both a 2.25" and a 1" thick version... I have the 2.25". Might explain why the taurus fan didn't fit. I assume I better replace my 2.25" with another 2.25", right?

 

[RonD]

There were single core and dual core radiators, singles were for manual transmission models in most cases, dual core for automatics or Rangers with AC

The shrouds for each were different, different tab placement at bottom and single core were deeper shrouds
I swapped in a dual core to my manual single core Ranger and had to get a dual core shroud to get it to fit right

 

[ratdude747]

There were single core and dual core radiators, singles were for manual transmission models in most cases, dual core for automatics or Rangers with AC

The shrouds for each were different, different tab placement at bottom and single core were deeper shrouds
I swapped in a dual core to my manual single core Ranger and had to get a dual core shroud to get it to fit right

Ah.

Any suggestions on replacement radiator brands? Leaning towards a Murray unit from O'rielly due to a good cost/convenience balance. But I'm open to other suggestions.

 

[fastpakr]

There were single core and dual core radiators, singles were for manual transmission models in most cases, dual core for automatics or Rangers with AC

The shrouds for each were different, different tab placement at bottom and single core were deeper shrouds
I swapped in a dual core to my manual single core Ranger and had to get a dual core shroud to get it to fit right

Interesting. It's been years since I did a swap, bit on my 86 the shroud didn't need to be swapped. Would be nice to know what years it was and wasn't required.

 

[RonD]

I wanted the single core with no trans cooler but it was a 7-10 days away, dual core was "in stock" so got that one
Thats when I found out about the shroud and lower rad hose, its different as well but mine did work.
1994 4.0l 4x4, manual

 

[ratdude747]

Ended up ordering an all-aluminum 3 core unit for cheap (same thickness as my 2 core)

Pardon Our Interruption...

I'll move the sensor over... from what I saw, it looks like Derale is using 3M VHB tape (which is tough stuff!), but I can cut and remove (and will re-adhere, probably using something more thermally conductive like JB kwik). Or I'll spend $20 on a new sensor. The controller comes in tomorrow, and I won't have the new radiator for a week; the existing radiator seeps but hasn't leaked yet, and I'll want to have the ranger back running before then.

Edit- JB weld isn't particulary good as a thermal adhesive. Sure, better than the stock 3M tape, but, there is a better product made just for this:

Arctic Silver Thermal Adhesive

www.arcticsilver.com

As much electronic and computer stuff I do as my other big hobby (besides my Ford trucks), I probably should have some on hand anyway.

Edit #2: Scratch the Arctic Silver Thermal Adhesive... pretty pricey, even by arctic silver standards (due to the silver content, no doubt). JB Kwik is the way to go...

 

[ratdude747]

Got the fan controller in yesterday.

All installed in final position other than the temp sensor. I just threw it on the top of the cold side tank for now; I'll remount it in the proper bottom side of the cold tank (and better route the cable) when I have the new radiator. I bled the cooling system with some lightly used coolant I had sitting (not going to waste my new coolant/water on a junk radiator) to ensure the top of the tank doesn't run dry. See attached pics (too lazy to post and comment them, sorry).

I was lucky in that when I opened the radiator support harness, the purple A/C wire was right on top. Made soldering a tap wire in a lot easier and cleaner (I liquid taped it after, and retaped the harness as needed).

The A/C override works great (60% fan when A/C on). Haven't gotten the fans to spin under temp control... but in last night's test drive, it didn't overheat either. Will take for another drive tonight... I'm thinking either I need to re-adjust/calibrate the controller, or the bad sensor placement is indeed my downfall.

 

[ratdude747]

New radiator came in yesterday. Installed up without issues, other than some of the brackets/clips being bent. They straightened out easily though. I didn't like the look of the radiator cap, so I swapped it for a new lever-type one. The drain cock is a plastic threaded plug with an O-ring... we'll see how well it holds, I didn't like the look of it either. But it only has to hold a handful of PSI at least.

I re-attached the fan sensor to the new radiator with super glue.... after first potting the inside of plastic sensor housing in JB plastic weld (which didn't fully cure after several days; seems I didn't get enough hardener?) Derale just had a bare board in a plastic cover with the original VHB tape providing the electrical insulation. Since I don't have more VHB tape and don't have time to wait on a new sensor, I figured this would be the best option to ensure the aluminum tank doesn't short it out.

Still not getting automatic fan control (at least as far as I know, had temp spikes as high as 217 degrees this morning). I'll be going to get a temp gun while I'm fetching Xmas gifts this afternoon and see... and re-calibrate the controller if needed. Worst case, I buy another sensor... or get one of the in-stream threaded ones they used to use with these and somehow add it to the system. Edit- It does indeed work... just too cold last night and this morning for it function. Will reply with pics.

 

[ratdude747]

All right, picture time.

Radiator installed:

Yeah, the zip tied air dam is a bit ghetto... I didn't have fresh clips that size and the old ones self-destructed upon removal.

Fan wiring re-routed:

Routing the cable above the trans cooler lines this time so I can cut two zip ties and have enough harness slop to allow me to lift the fan/shroud out with the fan plugged in. As it is, the connector is a PITA to access and the Chrysler lock is nearly impossible to release with the fan installed. Edit from 4.5 years later: the trans cooler line that I zip-tied the cable to melted the said cable's jacketing. I ended up wrapping the cable/jacket in that area with HVAC aluminum tape which seemed to have fixed it after 4 years and counting. In hindsight, I'd find or fabricate something that would keep the cable off said line.

Still have the same clearance with the new radiator:

Drove it a bunch today... fan controller does work. Only needed in drive-thrus and sometimes when I stop warm. Highest temp I saw (OBDII block sensor) was 217F... which I can live with since it's only a brief spike in certain occasions. Usually it runs 190-208 or so.

 

[DILLARD000]

Excellent writeup & pics.

 

[sgtsandman]

Good work and the temp range isn't bad. If it starts to get a bit of a concern when the air temperatures warm up for spring and summer, an oil cooler might be enough to get it under control. There are sandwich plates out there that have a thermostat in them. I kind of like the idea of not over cooling things if I don't have to.

 

[ratdude747]

Good work and the temp range isn't bad. If it starts to get a bit of a concern when the air temperatures warm up for spring and summer, an oil cooler might be enough to get it under control. There are sandwich plates out there that have a thermostat in them. I kind of like the idea of not over cooling things if I don't have to.

The controller is adjustable... 180 Degrees is the stock setting. We'll see in the spring. Although I use my A/C a lot, which may help due to the fan being forced to 60% minimum.

 

[ratdude747]

Have a few updates:

• Had zero issues with it this year up until yesterday. Including some pretty hot days, a trip to Branson, MO, and a trip to Tulsa, OK. Not even close to overheating!
• Had a controller (or sensor/wiring) failure yesterday. My ranger has been sitting for the most part since late September (driven a few times to ensure it doesn't sit too long) and yesterday my wife commented that the ranger was making noise... yep, something shorted out and is keeping the fan running at part speed all the time until the battery was ran most of the way down and I discovered the issue and pulled the negative battery cable. I haven't pulled it apart to see what went wrong (shorted sensor, shorted A/C input, faulty controller). I'm still within my 1 year warranty, thankfully

 

[RonD]

Assuming its a key on setup then only thing that could cause fan to run with key off is a bad fan relay, it may be under rated for the amps the fan draws so heated up and fused in the closed position
Or the fan motor is going bad and was drawing too many amps, causing relay to fuse closed

AC is a key on circuit so would be off and couldn't trigger the relay