Electric fan or new fan clutch/shroud for my 240z?

[Jayru]

Hey Guys,

My 72 240z began to overheat a few days ago while driving around town. So i've decided to overhall the entire cooling system (hoses, waterpump, thermostat, etc).

My question is, go with an electric fan or use a new fan clutch and radiator shroud (the one MSA sells for the 240)?

At first i thought going the clutch/shroud way would be cheaper, but after pricing it out, it's almost the same price if not more for the latter...

Any suggestions?

[moonpup]

Have you given any thought to possibly adding another core or two to your radiator? It may solve your problem and could save you money in the long run by having a professionally rebuilt radiator vs. a 30+ yr. old one.

[Arne]

My car had an electric fan on it when I got it, probably because the person who installed the ZX L28 in mine discovered at the last minute that the ZX fan and clutch wouldn't fit. I'm going to a 3 row core with the stock clutch/fan on mine, mostly because I don't like the cluttered look of all the extra wiring of the electric fan. But I live in a mild climate, so my demands aren't going to be too great.

But on the other hand, electric fans are probably more efficient, if you don't mind the extra wiring and electrical demand. But they do pull a lot of amps, and the stock 240Z charging system doesn't have a lot to spare.

[240ZX]

An electric fan will certainly work well but, there are a couple of things you may want to do additionally to eliminate the over heating. Flush out the block and radiator! Years of oxidation has built up on the walls of the block and radiator (a very thin layer/film of rust colored stuff) and it acts as an insulator....preventing good heat transfer between the block/radiator and the coolant. Also check your water pump. Upgrading to at least a three row radiator will make a significant improvement as well. I live in SoCal and have the set-up described on my 1970 240. The only time the fan kicks in is if I'm sitting a long while in traffic or shortly after I have turned the Z off. While driving, the temperature never gets high enough to activate the fan. Regarding the issue of high current draw from the fan and the low current capability of the Z wiring......to get around this you wire directly from the battery and use a relay to close the hot circuit from the battery to the fan motor. Generally, an electric fan kit will provide the temperature probe/relay to do this. Wiring for the electric fan can be neatly placed and secured to avoid a clutterd look. Hope this helps you in your quest!

Tom

[Jayru]

Thanks for the sugestions guys.

Interesting point about the radiator. I'm prety sure i have the original 2 row unit. So is the 4 row unit that much better/worth the money over the three row one MSA offers?

I used to have a 550hp supercharged mustang that had a three core rad, it always stayed nice and cool. Are Z's so bad that they need the 4 core?

[moonpup]

I'm in Houston and my 3 core had no problems and would probably be enough for your situation also.

Before you go with the MSA unit, you might check with radiator shops in your area and see what they'll charge to add a row to yours..

[240ZGL]

I picked up a 4 core at the MSA show sale on Saterday, Does anyone know if the clearnace is there to run the clutch and fan ? I remember the fan sitting very close to the old 2 core unit.

[LB260Z]

I'd go with the electric fan alone. you dont need the clutch with the electric fan and its thermostat.(removing the clutch fan will give you a slight "boost" in performance as it reduces drag on the engine too) I did this with mine and it works great.

[venom42]

Hi guys. I put an electric fan on my car a couple of days ago. However, it will not stay cool at idle. I installed a 2000 cfm 14" fan, but it is situated at the bottom of the radiator on the passenger side (just above the outlet). Is it because of where it is? Do I need a pusher on the front as well?

[ZSaint]

I have a 3.0 with 9.2 compression. I installed a 4-row rad and the larger ZX clutch fan. No shroud. I took it to Bremerton and had a 1-hour delay getting across the Narrows Bridge. (4 car accident) This came right after I pulled off the freeway. NO HEATING PROBLEMS! I did an hour of 'stop and go' driving and the new engine (600 miles) never over heated. I was shocked that the car ran so well in the heat. I vote for the 4-row rad/stock ZX clutch fan everytime.

[a7dz]

Once again what are you trying to do and where do you stop. I agree with whats been said about replacing the radiator. After thirty years they do not cool right. Has to do with metal properties. I have my radiator at our local radiator shop right now and it will be like new when I get it back. I am going to run a stock water pump, fan clutch and and upgraded plastic fan with out the shroud. Look at my signature and I will say I have never had a cooling problem with this car even in the hottest of climates. I can not advise anyone with a 240 to use an electric fan unless they upgrade the alternator also. I am going to use a ZX internally regulated alternator with the adapter that Arne supplies to us. The stock alternator is marginal at best with just the very minimal electrical draw. When I am done with this refresh all cooling parts will have been either rebuilt or replaced.

[nwcubsman]

Thanks for the sugestions guys.

Interesting point about the radiator. I'm prety sure i have the original 2 row unit. So is the 4 row unit that much better/worth the money over the three row one MSA offers?

I used to have a 550hp supercharged mustang that had a three core rad, it always stayed nice and cool. Are Z's so bad that they need the 4 core?

I replaced the radiator last year on a '73. went to the 3 row and I have never seen this car get hot. During our recent 100+ degree days, and this car in city traffic and rush hour traffic, the temp guage was right in its normal zone, just below center. So my opinion is the 3 row will take whatever you throw at it.

My other car has a 3 row as well. Drove it 12 straight hours with temps up to 104 degrees last August.

BTW, stock fan clutch on both cars.