I installed an oil cooler fan, ahead of the upcoming Houston summer. I hope it will help dissipate engine heat in rush hour traffic and at stop lights. I chose a 5” square computer fan, 1” thick. I placed it behind the oil cooler, between the cooler and the oil cooler bracket. I wired it into the ACC relay, so it always runs when the engine is on.

I had a lost power incident on a recent trip to Florida. After 1 hr on the freeway in 85 F weather, cruising at 72 mph, I had restricted power above ¼ throttle, and a CEL. This went away after the engine cooled down. I inspected the oil cooler, and found it half restricted due to bent fins. I straightened the fins, added an oil cooler guard, and added the fan. I will let the board know how it works out over the summer, and if the fan survives or dies.

 

Have any pics by on the install??
Also, did you use just a homemade screen for the oil coolers, or retail type (i.e. RB)??

 

I really doubt that a computer fan will survive even a little rain. Let us know what kills it.

 

couple of things here. 1st i have toyed with this idea as like you I suspect our oil temps are hotter than we think. Not proven but I am leaning that way. But on the fan issue --I decided not to do that. I think they may work well in stop and go traffic but not sure. 2nd i would worry about moisture anad possible damage to the fan from that.
I am in the process of measureing some oil temps to see if a 3nd cooler is justified. stay tuned results this june.
olddrager

 

You might have been better off installing the second oil cooler. It's been done by someone on the forum. As I recall, he was down under where even the MT cars are delivered with only one cooler. Of course, that would be considerbly more costly than the fan. Maybe when the fan goes you can take this route.

 

I installed the Racing Beat condenser screen and oil cooler screen. The install was easy, after the bumper and pan was off, and the components were first rate. I did not take photos of the fan install, as I don’t know if it will work.

The fan does push a lot of hot air out of the cooler at a stop, as I can feel the hot air push at the inner fender cover vent panel. The fan has survived direct spray from a hose, and a typical Houston tropical downpour so far. I placed the fan behind the cooler, with the blade to body gap facing away from the cooler. If the fan survives, I will post photos. If the fan does not survive, I will buy the waterproof type, but they are 10X cost

I just checked on the fan, it is still running, 3 weeks now. Those little fans are tougher than you might think

 

check your plug wires, make sure they are secure.

dont ask why i say this.

beers

 

"Those little fans are tougher than you might think "

Much tougher than I would have thought.

 

_I_ would ask, but then Mugatu would tell me to SEARCH! <g>

I too am surprised that the computer fan would hold up both to the automotive heat and outdoor moisture, but, good job!

It sure would be nice to have an oil temp. gauge. That's something I'm seriously thinking of adding. I'm wondering too, if in cold wx, that maybe a baffle plate should be installed on one or both coolers (MT). In the light aircraft I fly, they usually require a baffle kit to be installed over the oil cooler when the air temp is below 20 deg. F...

 

i have had the sudden power loss twice in 42k miles. first time was carboned seconday port valves.

the second time and the power loss acted the same as the first, but not near as bad. i watched the whole event on my scanalizer... the ecu was adding fuel, pulling spark..

well it was a loose trailing plug wire. car is back to running great.

beers

 

Just a quick update on the oil cooler fan - still running!
I think this is a useful mod, no lost power incidents with the fan installed.

 

maybe a link to said fan???? btw. the rules changed for me... i have a new motor now... it is amazing!

beers

 

a fan can actually restrict air flow. might be useful in low speeds though.

 

The fan is a Sunon, model kd1212ptb1-6a, 12VDC, 4.8W. Purchased at Allied Electronics.

http://www.alliedelec.com/Search/Pro...3EA9002B1D617F

Mounted at rear of cooler. Upper mounts are ty-wraps through the cooler fins. Lower mount is the oil cooler bracket. Main effect is at low speeds, which is what I was worried about (traffic jams).

 

120mm. i have an *** load of them around... hum. tie in to carputer with fanspeed..

to silly...

thx for the link.

beers

 

check summit racing they have a lot of choices on oil cooler fans. heck now that the temps have dropped--now in the 50-70 range in Ga i am having too LOW of oil temps--unless I drive her aggressively. A normal 15 mile drive oil temps dont get above 180F
olddragger

 

Is there any kind of thermostat for the oil coolers that reduces flow when cold? I think the oil cooler from my RX-7 FC has one.

 

Neither the factory workshop manualnor the parts manual for the RX-8 show a "thermostat" integrated with the oil cooler(s). I guess the FC part you are referring to is called by Mazda an "oil cooler bypass valve" which apparently controls the flow of oil through the oil cooler according to oil temperature--hence a thermostat, even though it is not identified as such. Perhaps there is a comparable device integrated within the RX-8 engine that serves the same purpose. Don't know.

 

This is a good topic.

Rotaries get nearly half their cooling from the oil.

 

Another update - almost 1 year now and the fan is still running! It must be the energizer bunny of computer fans!

 

wish you could do some temp monitoring.
OD

 

That too funny - I thought it would be toast by now. LOL

 

A one-year thread resurrection....I'm so proud!

Just this weekend I installed an oil temp gauge in my new 8 and I've already noticed that while creeping along in rush-hour traffic, the temp has reached 220 F. And that was at an ambient 82 F, which is at least 20 less than this car will see in a few months. Moving along at a constant 65 mph, the temp has stayed around 185 to 190, so I see a serious need for oil cooler fans on this vehicle.

Being a Mazda aficionado since 1972, I am a little disappointed that Mazda has been selling the RX-8 with inadequate oil cooling for our market's operating conditions. I've always considered Toyo Kogyo/Mazda to be in the top level of the automotive engineering heap and in flavors I like.

OK, rant: rant over...:

So today I ordered two of the same fans OMCWankel has had such good luck with, from Allied Electronics. 120x25 mm, 90 CFM Sunon part# KD1212PTB1-6A.GN
I also ordered a couple thermoswitches, Bud part#TS-15, because I just don't want the fans to run whenever the engine is running. That probably doesn't hurt anything, but I don't want them running when they are not needed. They are adjustable from 80 to 170 F, so finding just the right place to mount them should be an interesting exercise.

I'll post results when I have them..............

 

Take pictures please.

 

Mercury, I would also be interested in seeing some pics of your final installation. This is something I will likely do as I prepare my car for the track.

A couple of questions. I've done a bit of research on fans and Sunon has a variety of 120mm units. Is there a specific reason, other than someone else used them, to pick that particular fan? Sunon also touts a line of weather-resistant fans that would seem to be ideal for this application, but there is little else on their web site beyond a news release.

Will the switch you are installing sense the ambient temp in the engine compartment or the temp of the oil cooler "skin"? Where do you intend to mount the switch?

TIA,

Larry