Fan Quiz

[ensys]

 

So I am wondering about the aux. electric cooling fan for the ('77) 280Z.

- Most references call the fan "optional"; any opinions about how frequently 280s went out the Factory door with this fan mounted on the radiator?

- Or was the fan more often an after-purchase, dealer installed kind of thing.

- And now, the $64 question: exactly where are the two connectors for the fan to be found on the stock harness?

Thanks for looking.

 

[dmorales-bello]

I've had two 280s (a '77 and a' 78) and had no idea an auxiliary electric fan was ever offered as optional equipment. 

[S30Driver]

If there was an "optional" electric fan, it worked in conjunction with the factory AC system, to move more air thru the condenser.

My 77 has one, it is aftermarket, installed by the original owner.

[Dave WM]

2 hours ago, S30Driver said:

If there was an "optional" electric fan, it worked in conjunction with the factory AC system, to move more air thru the condenser.

My 77 has one, it is aftermarket, installed by the original owner.

I was thinking AC also, perhaps as added if a 134a conversion was done.

[wal280z]

10 hours ago, ensys said:

 

So I am wondering about the aux. electric cooling fan for the ('77) 280Z.

- Most references call the fan "optional"; any opinions about how frequently 280s went out the Factory door with this fan mounted on the radiator?

- Or was the fan more often an after-purchase, dealer installed kind of thing.

- And now, the $64 question: exactly where are the two connectors for the fan to be found on the stock harness?

Thanks for looking.

 

Well, I looked at the harness I removed from my first '77 (splices and cuts everywhere), but could not find any EXIT point of the harness of the WHITE/RED STRIPE and the BLUE wire, noted as "FOR U.S.A." on the wiring diagram.

What's even more confusing, and I double checked the original black and white from the FSM, is that both aforementioned wires are fused from opposite sides of the fuse box. Didn't realize that until just now.

@Captain Obvious, @EuroDat, does that make any sense to you? I poured through the FSM and could not find any written documentation regarding this, even in the AC supplement (I had thought it may have been part of the AC sub-harness, but the FSM does not explain it, it only shows it on the fold-out diagram in the back.....

Edited December 23, 2018 by wal280z
forgot to attach diagram snip

[Captain Obvious]

There has been some discussion about that cooling fan motor sub-harness in the past. Unfortunately the pics are dead because photobucket sucks, but here's some threads:

https://www.classiczcars.com/forums/topic/46256-always-hot-connection-for-radio-install/?tab=comments#comment-420468

https://www.classiczcars.com/forums/topic/52262-recommendation-for-new-radiator-and-elctrical-fan-for-280z/?page=2&tab=comments#comment-478260

I reattached a couple of my previous pics here... The two connections for that sub-harness are under the dash above the passengers right knee. Tucked up to the right of the glove box:

[wal280z]

38 minutes ago, wal280z said:

Well, I looked at the harness I removed from my first '77 (splices and cuts everywhere), but could not find any EXIT point of the harness of the WHITE/RED STRIPE and the BLUE wire, noted as "FOR U.S.A." on the wiring diagram.

Dang, I just realized my goof - I was looking at the ENGINE BAY harness, not the body harness INSIDE the cabin (as the diagram does show)

6 minutes ago, Captain Obvious said:

Thanks @Captain Obvious for clearing up my confusion.....

[EuroDat]

I have wondered about this sub harness option as well. Those same wires are in my harness too. I thought it might be for the AC, but my Californian car has AC and no optional cooling fan.

Could it have been an option for the cars sold with the tow bar? Or maybe the developers thought the N47 heads would have heat problems in certain areas with lead free fuel and exhaust liners generating more heat? I am yet to see one or even a photo of one.

A while back, I toyed with the idea of running a 280ZX fuel injector cooling fan from this circuit and using a delayed shutoff relay. I have the fan, but it's way down on my to do list.

 

[Captain Obvious]

7 hours ago, wal280z said:

Thanks @Captain Obvious for clearing up my confusion.....

My pleasure. I can tell you where to find those connections, but I still can't tell you why they're there.  Haha!

If I had to guess, I would dovetail off something that Chas mentioned... I suspect those connections are some sort of precursor to the valve cover mounted injector cooling fan assy.

[ensys]

 

All:

 

This has been very informative, indeed.

I too, am surprised by the location of the stub outs; I also was looking in the engine room for them, since the parts manual image of the fan didn't show a very long harness. Very curious.

On the plus side, it promises to simplify my re-tasking wiring quite a bit.

Tho my Calif. car w/A.C. had no such fan, I still think it was intended to address heat issues, particularly in urban situations (tho admittedly, it would be useless to combat heat soak). Still, it was offered; perhaps the key is "optional", and was born as a potential remedy for disgruntled customers in particularly hot climes.

So, would it be correct to assume that no one has ever seen one installed?

 

 

 

 

 

 

[EuroDat]

3 hours ago, ensys said:

 

So, would it be correct to assume that no one has ever seen one installed?

 

I have never seen one or heard of anyone seeing one. It seems to coinside with the change to the N47 head.

My guess, it's probably prep werk, but never made it further than that. The developers probably thought, "if it becomes a problem, we can offer it as an option or do a recall, and the harness will be ready."

I think trying to find one would be like trying to find a woolly mammoth;)

[zspert]

While the cooling fan can be seen on the microfiche parts film I have yet to see one in almost 50 years as a Datsun/Nissan mechanic.