Yep, I do plan to post plenty of good photos starting with the parts I ordered, as they arrive.

The main reason I chose this fan was its slim 25mm thickness. I think the clearance between the oil cooler support bracket near the bottom is too close for the next-size-up fan, at least if I want to be able to position the fan near the bottom of the oil cooler. I'll try to reaffirm this during installation. The next-size-up fan is 38mm and gives about 50% more airflow, which is great but I think I don't need that much.

The thermoswitches appear to have a metal plate as its mounting base which is probably also its thermal input. If it is, it should be ideal for mounting (tie-strapping?) directly to the "skin" of the oil cooler. This should give the quickest response to an oil temp spike. Since the max temp on these thermoswitches is 170F, I suspect the fans will be running anytime the engine has been running awhile, but I may be pleasantly surprised. :D:

As far as the weather-resistant fans - it does seem a little nutty to expect an electrical device that was designed for use inside a desktop computer or in a server room to have a long and happy life just ahead of Mercury's front tire and in the airstream a few inches above the pavement. :crazy: But I am encouraged by OMCWankel's testimonial, especially since it looks like his car is operating in the tough environment of Florida, compared with mine being in AridZona. Mine will probably die from heat stroke vs. drowning! :wink2:

Yeah, I noticed the "fatter" fans with a bit more air flow. On another point, when looking at auto radiator/cooler fans, they are either pushers or pullers. Meaning that the pushers have to be located in front of the cooler and the pullers on the back side. I don't see such a classification for the computer fans and looking at the fans in my computers, I conclude that they probably are all pushers and so must be mounted on the front of the cooler. Is that your understanding?

That sounds reasonable. Will be interested in what the instructions have to say, if anything.:)

As I said, I've been looking at fans designed to work in the auto radiator/cooler environment. Be Cool has a generic 5.6" circular fan (#75012) that looks like it may fit. I'll be doing some measuring in the near future to find out. Unfortunately, that fan is $92.00 at Summit Racing, so it certainly is not competitive pricewise with the muffin fans. But, for a track car that will see high temps in the summer, it would be worth it to me to have a happy engine. If you consider a reman/rebuild would cost several thousand dollars, $250.00 would be cheap insurance. In any case, I will do something in the way of oil cooler fans before I take to the track with this car. In the meantime, I have my dependable 2nd gen RX-7 track car that is like the energizer bunny.:)

One other thing about the muffin fans. In searching through all the supplier catalogs I have on hand, as well as on line, I see that the operating environment for most of these fans includes a max temp of about 80 degrees celsius (176 F). That seems a bit low for the environment it would be operating in. But if OMC Wankel has gotten good life out of them, and since they only cost $12.00, I guess you could easily replace them if they die an early death.:lol2:

[QUOTE=Go48;2376192]On another point, when looking at auto radiator/cooler fans, they are either pushers or pullers. Meaning that the pushers have to be located in front of the cooler and the pullers on the back side. I don't see such a classification for the computer fans and looking at the fans in my computers, I conclude that they probably are all pushers and so must be mounted on the front of the cooler. Is that your understanding?QUOTE]

The Summit fan is a standard automotive type fan with one flat mounting surface and must be ordered in either a pusher or puller style. The muffin computer type
fan, has two flat mounting surfaces and can be used as either a pusher or puller.

Thanks for unfreezing my brain. I shoulda thought of that.:banghead:

Oil Cooler Fans, Stage One
 

Well, it took me just a few hours to actually do this job but a lot longer (obviously) to get it posted to the forum.

I took these photos as I was working on the install. That is why some photos show unprotected wires and others show the fiberglass sleeving over the wires. Kind of a work-in-progress and I wanted to get as many good shots of the components as possible. There are 13 photos spread across three forum postings.

In the fourth of these photos you can see the metal extender I fabricated to relocate the original oil cooler bracket. This was a simple hacksaw job on the brackets that came with my B&M transmission cooler. Worked perfectly for this, except the first one I cut a bit short. Even this thin fan needed more room.

The tie straps are Thomas & Betts nylon with a metal "tooth" so they are better than average but I would feel better if I had used metal straps. These straps withstand heat well, but they will still get brittle and eventually break.

Oil Cooler Fans, Stage One
 

Here are a few more photos as the work progressed....

The thermoswitch is mounted off to the side of the cooler, out of the airflow. I wanted to avoid blocking the path of air and that may have been a mistake because the heated air flowing over the switch may have been a more accurate method of measuring the oil temp than what I have here. At first, I had the adjustable turn-on temp at the max of 170F and the fans never came on even with oil temps well above 220F. So I adjusted the switches to 130 and they seem to kick on at about 210F oil temp.

Since installing these I have experienced quite a few freeway traffic jams (normal for rush-hour Phoenix) in which I have to drive in what I call Parade Mode. This is creeping along between 10 and 25 mph in first, second or maybe third if on a downhill. I don't want to lug the engine down to too slow an rpm and at the same time put a load on it, but I have been seeing the importance of low rpms when there is no airflow through the oil coolers. At idle, there seems to be no problem at 100 F ambient or less. Over about 30 mph, there seems to be enough airflow through the coolers to handle running along at 3 to 4k revs. This is totally unscientific testing but just my observations during the few months I have owned and commuted in this car. So the worst condition is in Parade Mode where the heat entering the oil system is unable to escape due to a lack of airflow through the coolers.

I'll probably never track this car but I can see any condition that pairs high engine rpm (even as low as 3 to 4k) with slow vehicle speed is bad news for the oil temp.

Hey Mercury I would really like to know how this works. Being in the same neck of the woods and all.
I've had Mazda Engineers over twice from MNAO trying to deal with my overheating issues. This coming summer will tell.

Oil Cooler Fans, Stage One
 

OK, here's the last one.....

I gave these posts the title of Stage One because I plan to replace the air-sensing thermoswitches with a thermoswitch mounted in the Racing Beat adapter where I am also measuring the oil temperature. I bought an AutoMeter 200 F degree switch that should react quicker and be closer to what Mazda should have designed and built. Besides, tie strapping the temperature sensing component to a heat exchanger seems just plain wrong, now that I see it.

This fan covers about one third of the oil cooler. A larger diameter fan could be used, but may not be necessary. I'll see when the ambient temps rise into the teens (like 115 or so) during an afternoon drive home in heavy traffic.