Kalidor

Hello all. New owner of an 1990 RX7 (GXL) that, so far, runs great. I got a lot of documentation that I think made the price a good buy.

I have found a questionable part in there, that while it doesn't seem to affect much of anything when in operation looks out of place (to the point of ugly) and I wanted to confirm it was after market.

I found an electric fan sitting under the fan shroud bolted to the radiator (this is in addition the what the Haynes calls the "Mechanical fan with Viscous clutch). Based on the direction of the clutch fan when the motor is running, and the direction it turns when the electric fan is on (no motor); I concluded that they are pushing air in opposite directions. Finally this is all wired together to a relay, the battery and a switch in the cabin.


My suspicion is that this is a fan that was installed by the previous owner as a way to cool down the engine after driving it. Going back to the Haynes manual the optional fan is bolted on the front of the radiator, not the back under the shroud. Also I wouldn't want to run it with the stock clutch fan because if they are blowing in opposite directions won't they just be fighting each other and failing to cool anything?


My plan is to take the car into my local Mazda Dealer (which being Toronto, I hope has at least one Rotary tech) and ask them to checkout the cooling system. I am definitely going to get the radiator flushed cause its running a little hot, have them check the thermostat and have them check out that aftermarket deal.

I would like opinions on if it is in fact an aftermarket attachment. Ideally I'd like to see the coolant system relatively stock to see how it performs. If I do end up wanting an electric fan, I would want to have the electrical completely redone so it doesn't look like the installer is learning how to wire using one of those 1001 lab kits from Radio Shack.

Thanks in advance.

Aaron Cake

iTrader: (1)

Sounds like someone stuck a fan on there for some unknown reason. If the car cools fine with the extra fan turned off, then just remove it and clean up the wiring mess.

Don't bother with the Mazda dealer to check the cooling system. Any competent shop can do it for you and the dealer will probably just overcharge and get it wrong. They don't like working on RX-7s.

Kalidor

Thanks!

I know you aren't exactly close but you have any recommendations as far as a mechanic or shop in Toronto it would be good form a relationship with?

Aaron Cake

iTrader: (1)

No idea. I hate mechanics.

Rx-7fetish

Ha Ha Ha, me too, and to the op, it sounds like someone was trying to increase the cooling efficiency but didnt have a clue what they were doing. Like the previous suggestion, take the electric fan out and see if it cools any better. If t does i dont see the need to take it anywhere

Kalidor

Eh-heh! I am not too hot on mechanics either. But there's only so much a computer engineer can do on car. I can do the basics, but I am worried if I need something I will eventually need an engineer and best to build relationship before "stuff happens"(TM).

Plan right now is :

1) Flush the Rad, see how she responds. (just to get an idea)

2) Afterwards remove the fan and clean up the electrical, then take a look at the heat again.

I suspect I'll see an improvement in both steps. Simply for airflow reasons if nothing else on step 2.


Thanks for the suggestions!

Aaron Cake

iTrader: (1)

I'm a computer engineer. Well, not really. I'm a computer tech. I have to live with all the bonehead decisions computer engineers make and actually have the job of making it work.

Joking...

What I failed to mention previously is that the Canadian Forum is a good place to check for shop recommendations. There are a lot of Toronto area people there...

If that little fan is required to keep the car cool, then something is wrong.

arghx

iTrader: (3)

this isn't the factory electric fan on turbo and automatic n/a cars?

Kalidor

Aaron Cake: Far as I am concerned tech and engineer are roughly the same thing. In the end the best techs think like engineers. The boneheads that write half the software out there .. I dunno what they are .. but I refuse to give them a title like engineer.

arghx: I hope not .. it's an NA Standard. Plus, if I am reading the Hanyes Manual (and FSM) correctly, the fan you mentioned should be on the front of the radiator, not the back.




I've certainly been driving it around. About 6 hours worth since I finally took possession of it Saturday and heating isn't a problem as long as I have a half decent pace. It's only during stop and go it seems to spike up a little which I think could easily be a combination of the rad needing flushed, and bad airflow since there is this silly little fan sitting in between the clutch fan and the radiator.

Either way I'll take a picture tonight before driving it out and see about learning to post pictures here.

Kalidor

Wow a year later. I should put closure to this thread. A week after the above I asked Downtown Mazda to pitch the e-fan, and flush the rad. Didn't help.

Then went to the next option, and had the clutch on the clutch-fan replaced. According to them it was fine, and to the best of my diagnostic ability (following the Haynes manual) I thought the it was fine too. We were wrong. Fixed the problem immediately. Not bad for 3 days and 275 bucks of work. (Yeah I know I could have done it for cheaper myself but not in a basement apartment garage and definitely still working on getting both my ability and confidence in mechanical aspect up.)

Thx to all the suggestions, and I already thanks Aaron in person.