Using a Flex Fan instead of the orginal Fan and clutch

Discuss (and cuss) the Nissan LD-series OHC Six diesel engine, popularly available in the US in 1981-83 Datsun/Nissan Maxima Sedans & Wagons.

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Using a Flex Fan instead of the orginal Fan and clutch


Post by theminotaur »

(Moderator, feel free to move this post else where if it is in the wrong catagory)

I have a 1983 Diesel Nissan Maxiam, and since I purchased the car I done several modifications including:

(1) Install a stainless steel exhaust pipe and perforated stainless steel mesh, similar to the semi trucks that allows the exhaust smoke and soot from not covering the trunk. (How do you remove the soot from the paint?)

(2) Install the orginal rack accessory on the trunk (more cargo space).

(3) Add a coolant filter system, that uses a spin-on filter similar to an oil filter.

(4) Add a cold air intake using a plastic airfilter housing to direct the cool air into the engine. Also replaced the orginal air filter with a cone type.

(5) Replaced the orginal rear cooling/heating (under the seats) duct with a electric cooling unit, for increase air floor.

(6) Refurbish the center console (a night mare process because the cheap plastic hard to work with and cracks so easly), and replace the orginal radio and tape player with a CD player.

(7) Wrap the entire exhaust pipe with thermal insulation (looks like first aid bandages) to keep under the car body cool.

(8) Added a cooling system that uses the condensation water from A/C coil to cool the A/C condensor coil in front of the radiator.

(9) Added (2) electric fans for the A/C condensor coil (I was told that 134A is less efficent then R12 and to remove heat better electric fans would help. I am unsure if this better or not?)

>--->>>(10) My final project is can I replace my car's orginal Fan and clutch, with a Flex Fan (I read that a Flex Fan flattens out at higher engine speeds and increases engine horsepower) is this possible? I would need some sort of adapter plate from the water pump to the flex fan..any suggestions?

By the way any suggestions on how to obtain electric versions of the following items to reduce horsepower losses: Waterpump, Powersteering Pump, and A/C compressor (The Toyota Pirus uses an electric A/C compressor).

Note any of the modifications listed above I more then happy to explain how to install and or create it. Some items can't be purchased, and have to be bulit from scratch.

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Post by kassim503 »

Honestly, im gonna advise against it. I personally swapped to a flex fan a while ago but went back to a clutch, you lose a significant amount of power, even when it flattens out. Also the puller has a overdrive ratio thatll put the flex fan way past its designed redline. A few more things that didnt work is that there was no premade adapter that was available to fit the fan properly, so machining is required to fit the WP hub, also after I lost a radiator to a fan it became apparant that the WP is not designed to handle the stresses of a metal fan (see '69 240z steel fan's). I also halfway lost another radiator to the flex fan flexing into the radiator. Finally, its hard to find a full size flex fan that will actually fit into the space provided. I had about 3/4 inch to the rad and less than a hair's gap to the PS idler bolt. If you are looking for power try to jam a 90's ford taurus electric fan in.

The plusses was it always kept the car cool, but the same could be achieved with the OEM clutch fan after a little adjusting. Also when it gets to howling itll scare people away for miles :lol:

Personally, I believe the losses from the pumps and compressor is so small you wont lose horsepower from wide open. The A/C compressor automatically turns off at wide open operation, and the PS pump dosent create real drain until you turn the wheel, and the water pump, well, its on a overdrive pulley for a reason I guess. But if you must, there are definitely some underdrive pulley kits for the Z cars out there that you can jam in.
'83 maxima sedan, l24e, a/t, black

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Post by davehoos »

I bought an 1978 810 recently and are upgrading the cooling system.
Its auto with no a/c so it only has a simple 4 blade fan and the colw long gone.i was looking at a 720 L18 4 blade-large triangle blades.but the 2 i have show signs of decomposing.

I have several clutch fan pumps but these have been sitting around.
its got a new NPW pump fitted.its got a very small dia pump bearing.

what i decided is to fit an electric fan natra L20B 910 radiator V's the tokyo copy radiator.i have seen a 810 electric fan rad for some time in working order.the holes lined up if I swap the side bands over.[fit rad upside down].

I then looked at a late 80's mitubishi magna radiator.its made here by the same company.has 2 denso fans bolted to it in one version,the main one has a water temp switch and A/C version comes factory with a large pusher 2 speed fan out in front.older version had a small fan that was good to cool the alternator.totals about 400+ watts.

its heavier than the datsun rad and the same size with as the hole in the support pannel.both outlets are on the right side and trans coooler is decent size with an extra denso oil cooler in series.

it sits on 2 pins,and top has a vibration mouting bolted to it. is very basic.these cars are sold in USA but the narrow body gallant would be more common.

this week a Volvo 945 turbo came in to work and looks a good size with a half decent fan cowl setup.and simple surge tank.
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