Recommendation for new radiator and elctrical fan for 280Z

[Zed Head]

I've looked for a good switch for a fan in the past (it was for an injector cooling fan, not radiator).  Difficult to find.  The ZX switch is set to a high temperature, it's more of an extreme heat switch, to battle the heat-soak problem.  Probably wouldn't work well for radiator cooling fans, it turns on at 210 F or around there.  I think that many people who use the electric cooling fans use programmable systems, with a thermocouple.

 

Here's a general article.  http://www.hotrod.com/how-to/engine/ccrp-1111-electric-radiator-fans/

 

Good luck on matching the thermostat housing threads.  Most people just run a tap through the hole and repurpose it.  Once they find a sensor that they like.

[rossiz]

yes, freeze plugs are a press fit. they are either brass or steel and must be destroyed to remove. most of the time you can use a drift pin punch or large screwdriver and hammer one edge until it pushes in, pivoting the plug until you can grab the edge that popped out with some pliers and pull it out. it's a pita to get them out when they stick - i drilled a 1/4" hole in the stubborn ones and hammered the tip of a cats paw in and pried them out (always exciting to bring carpentry tools into the engine bay). 

 

there is a drain plug on the drivers side of the block, back by the fire wall down about halfway - it has a square fitting. you can get it out and peek in to see the condition of the water jackets and if you're satisfied all is ok leave the freeze plugs alone. i would use a good light and a piece of coat hanger to dig around and be sure. the crud/sludge i found was primarily in and around the freeze plug area, as this is towards the bottom of the block where things settle. if a PO ran with just water (no coolant, which has rust inhibitors) and ever used some stop-leak stuff (designed to coagulate and seal off small leaks) the mixture can become a poopy stew that can block the cooling system. 

[Marios280Z]

Thanks rossiz.

[Marios280Z]

What would be a good place to pick up 12V ignition signal to drive my electric fans?

[Mike W]

I've been meaning to post about this topic and just haven't had the time to get to it until now.  Hopefully this is not too late to help you out.

 

First, I have been down this path multiple times with Champion radiators and electric fans.  My first implementation used an adjustable temp control module that required a probe to be inserted into the fins of the radiator.  Although this setup was fully functional and provided the ability to select the temp at which the fans turned on, I never particularly like the idea of the probe going through the fins of the radiator itself, so I searched for a more elegant solution.

 

I found a really neat product from a company called Dakota Digital, which is essentially a digital fan controller that is highly programmable.  You can set fan on temp, fan off temp, have the fans run for X minutes after the car has been shut off, etc.  They also provide a temp sensor specifically made for this unit which I also used.  I ended up removing the coolant drain plug on the drivers side of the engine block and replaced it with the sensor, although I did need a thread adapter to make this work.  The setup works flawlessly and I have had no issues with it what so ever.  You can find more about it here:

 

http://www.dakotadigital.com/index.cfm/page/ptype=product/product_id=852/category_id=403/mode=prod/prd852.htm

 

I ended up mounting it in the glove box so the controls and display are easily accessible from the interior of the car. 

 

I also found that the generic type fans that came with the Champion radiators were marginal at best.  In the hot summer weather here in Texas I found that the combination of the Champion radiator and the generic fans could not keep up with a high heat situation in traffic.  I would find in this situation that my temp would continue to go up while sitting at a stop light and this was not an acceptable solution to me.

 

So I ended up changing out both the radiator as well as the fans.  Went with a radiator from a company in New York called Wizard Cooling.  These guys were unbelievable in the service they provided to me and their product (all made in the good old USA) was far superior to the Champion both in terms of build quality as well as cooling performance.   They even designed and made a custom fan mount for me which was a significant upgrade to the "tie wrap" approach that the generic fans used. 

 

For the fans I went with two 12 inch Spal fans.  Although a lot more expensive than the generic type, these things are unbelievable.  They sound like a turbine engine when they start up and their cooling capability, along with the Wizard radiator is nothing short of spectacular.  I can be sitting in traffic in 110 degree weather in Austin and my temp will begin dropping as soon as the fans kick in.  Never had any sort of overheating problem since I made this change.  You can find more about Wizard cooling here:

 

http://www.wizardcooling.com/Datsun-s/1826.htm

 

I don't have access to my picture files now, but if anyone would like pictures of my setup I'll be happy to post those when I get home this evening.  Just let me know.

 

Hope this helps and is not too late.

 

Mike.

[Zed Head]

One thing that's not often mentioned with the electric fans is the extra draw on an already weak electrical system.  The 60 amp stock alternator typically can barely handle the lights on at idle.  Those fans can draw some amps.

[Marios280Z]

Mike W,  I went similar way you did the fist time around. I got Champion 3 core radiator. I also got their dual fan shroud  that they just recently started to offer(which I had to modify in order to really fit tightly, it was  a missed opportunity on Champion's side and I let them know about that). I got two SAPL 11" fans that draw 9.5 AMPs each (I got the 12" first but hey were just a pinch to large and they were sticking about 1/4 " outside the radiator on each side). I used inline radiator hose adapter to mount a thermo switch. I found one that had 1/8 NPT threads that matched my wiring harness that I got from Derale: http://derale.com/products/electric-fans/fan-controllers/single-stage/standard-transmission-cooler-mount-kit-11-32-detail  I have seen the Dakota fan controller, but that was just a bit too expensive for me at this time. I'm still putting all this together. Here are few pictures of the shroud modification and the sensor adapter.

 

This is the shroud on the radiator. It has long sides that wrap the radiator and use radiator mounting holes

 

As a matter of fact the sides were a little to long and created gaps on top and the bottom of the radiator as shown here

 

So I decided to shorten it a bit

 

 

 

And here is the sensor adapter on my new silicon hose

[Marios280Z]

Guys, I am still looking for recommendations for where to pick up 12V ignition signal to run the fans.

[Captain Obvious]

I'm not exactly sure what you would be using the 12V ignition signal for.

 

Are you planning to use this connection as a high current source to actually power the fans? Because if so, then my answer is.. "There isn't one. Connect right to the battery and use a relay to switch the high current source." You would control the relay with a low current source that goes hot in ON and there are plenty of places to pick the up.

 

On the other hand, if you're looking for that low current source that goes hot in ON to control a relay or a control module of some sort, there are several ways to do that. But I want to figure out if that's what you're looking for first.

[Marios280Z]

On the other hand, if you're looking for that low current source that goes hot in ON to control a relay or a control module of some sort, there are several ways to do that. But I want to figure out if that's what you're looking for first.

 CO, yes this is what I'm looking for, a low current to activate the relay. Take a look at the wiring diagram of my harness (attached). The connection in question is circled in red on page two.

 

16720 (1).pdf

[Captain Obvious]

Gotcha. So you're looking for a low current source that goes hot when in ON.

 

There's lots of ways to do that, but one of the simplest would be to tap into the white/black that goes to your ignition module and your ignition coil. That wire goes hot in ON and START

[Captain Obvious]

And this talk about fans reminds me.... If you're looking for something under the dash instead of the engine compartment, there are two curious signals up above the fuseblock that show up on the upper middlish of the wiring diagram labeled as "To Cooling Fan Motor Sub-Harness".

 

One of those wires is hot at all times and the other is hot in ON and START. You could use one or both of them to connect to your module, especially if you're locating it in the glove compartment. There was some discussion about these wires in the past in this thread:

 

http://www.classiczcars.com/topic/46256-always-hot-connection-for-radio-install/