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Rx-2 electric fan / radiator question

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Old Mar 23, 2004 | 02:31 AM
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Rx-2 electric fan / radiator question

Hi,

I have almost finished putting an 85 12a into my Rx-2.
The engine is moved forward due to the use of a 79 S1 transmission. There were no clearance problems until now...
But now I need about 0.3 inch more space to mount the fan.
The original Rx-2 radiator is mounted to the frame with rubber mounting blocks. Is it safe to remove these blocks and bolt the rad to the frame directly ?
Has anyone ever tried to remove these blocks ? I'm afraid they will snap on the rubber part.

I have an electric fan lying around as well (it needs the same space as the original one so it doesn't solve the problem above). Can anyone recommend an adjustable switch that will allow the fan to turn off and on based on the under-hood temp ?

Thanks !
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Old Mar 23, 2004 | 12:14 PM
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I removed the rubbers and used smaller rubber washers for some vibration barrier....otherwise, everything fits fine and keeps cool. I am also using an electric fan, only about 1/2 inch from the pulley to the back of the fan, but I've never had a problem.
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Old Mar 24, 2004 | 02:02 AM
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Re: Rx-2 electric fan / radiator question

Originally posted by multirotor
Hi,

Can anyone recommend an adjustable switch that will allow the fan to turn off and on based on the under-hood temp ?

Thanks !
Not one that works. I just use a manual switch for mine. When I get stuck in traffic or gets too hot out and I see the temp start creeping up, I just turn it on, otherwise, no fan at all . . .
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Old Mar 31, 2004 | 08:12 PM
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Your best bet would be to remove the old RX-2 radiator and upgrade to the RX-7 radiator. The only problem your going to have is that the RX-7 radiator is longer and is going to hit the lower valance panel which you would then have to take off the (2) 8mm screws. You also have to open the mounting hole to make the match the RX-2 studs. The more updated radiator works a hell of a lot better than the older stuff. You can take off the rubber washers and use shorter ones found at your local hardware store. Well good luck with that.

Last edited by mannyrx2; Mar 31, 2004 at 08:14 PM.
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Old Mar 31, 2004 | 11:53 PM
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don't forget you'd have to relocate the oil cooler if you do that, which means you'll need new oil cooler lines . . . a pretty expensive proposition if you have to buy new fittings and stuff from Racing Beat . .
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Old Apr 1, 2004 | 12:20 AM
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Thanks for the replies. I always heard that the older radiators were better than the newer ones (3 core versus 2 core) ??
Is the Rx-7 radiator thinner than the Rx-2 rad ?
The series 3 radiator will require relocation of the oil cooler but a series 1 would not, right ?

Anyway, I took the Rx-2 out for a spin after over one year of being engine-less. No fan, no alt, no muffler, lots of noise and lots of smiles (my smiles, not the neighbours).

I am very happy. It's my first engine rebuild by myself and it runs, starts cold and hot, it doesn't leak and makes a nice brap brap sound.
(It was also my first porting job)
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Old Apr 1, 2004 | 12:27 AM
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the RX-7 rad is taller and thinner than the stock 2. If your oil cooler is below your radiator and you want to put in the tall RX-7 radiator, you'll definately need to move the oil cooler somewhere . . you could do the lame 84-85 oil-to-water cooler that sits under the oil filter instead, but those aren't as efficient as the oil-to-air cooler that is stock on all mazda's through 83 I believe.
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Old Apr 1, 2004 | 12:42 AM
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Right, an 85 rad is taller than the earlier rads because they had more room (due to the water-oil-cooler)
I think the 83 and earlier rads are similar in size to the Rx-2 rads so if an 83 rad would be thinner than a stock Rx-2 rad, it would be the solution to my problem.
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Old Apr 1, 2004 | 04:49 AM
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From: Elsenborn, Belgian Eifel
You can use an E-fan in front of the rad, controlled by a thermoswitch. The sensor for the switch must go into the watercircuit though. You can modify a waterpumphousing for this. Kempower has several fans and controllers (the really good ones are expensive though)
Of course if you want to use your own fan (which probable is a pull-type fan) you'll need to see how you can place that between the rad and engine.
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Old Apr 5, 2004 | 03:41 PM
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Problem solved: The rad is vertical and the engine is tilted a little so the fan only did hit the lower side of the rad. So I removed the two bottom rubbers and kept the top ones, tilting the rad in the same direction as the engine. That gives me sufficient space.

I checked one of my 1st gens and the 1st gen radiators are bolted to the frame without rubbers, so I think it is safe to remove the rubbers on the Rx-2 too.
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