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I began tinkering with electric primary cooling fan conversions in Volvo 240s back around 1997 after having less than a successful time keeping my '84 245 Turbo from running too hot during warm 100+ degree Southern California summers using the stock pulley fan. I then developed this page beginning in 1999 to share this info and I've been updating it on occasion ever since. Basically, this page will outline some fairly simple and inexpensive primary electric fan conversion ideas for Volvo 240s. Some ideas worked, some not so well. Some of these ideas also work for the 740, however it should be noted the 740 Turbo has less room between the radiator and water pump pulley, so some fans shown in this page may not fit in the space.
While there are many options for your Volvo when it comes to keeping cool, these are just a few. This information is presented at face value with no specific claims of magical performance, other than my own experiences.
|For any electric fan
installation, make sure that
fan is capable of turning itself on
reliably if your engine starts to
There are two primary reasons for performing an Electric Fan Conversion. The FIRST is to reduce the engine drag at highway speeds. In theory you should gain a little horespower.
The SECOND reason would be to reduce the amount of stress on the waterpump. 240s can go through water pumps faster than a typical car and it's a good idea to change them as preventative maintenance. The loads placed on the water pump bearings by the alternator and a huge belt-driven fan can shorten its potential service life.
|You will need to decide for yourself if
your fan clutch is best or if an electric fan is best. If the electric
fan is big enough and really powerful, it can equal the cooling
performance of a heavy duty fan clutch. Most electric fans will not come close.
Also an electric fan may not be as reliable as the mechanical
fan. Electrical stuff fails. If
you decide it's best for your Volvo to keep the belt-driven fan,
you may want to consider the option of a heavy duty fan
An interesting bit of information I discovered while trying out the below electric fan conversions over the years.
All electric fans I tried were INFERIOR in cooling capactity compared to a heavy duty tropical fan clutch, EXCEPT for the huge FORD fans at the bottom of this list.
More info on the Heavy Duty Tropical Fan Clutch can be found in this page:
VOLVO 2-Speed FAN RELAY Basics.
Lots of people are using this relay to control 2-speed fans because it's cheap if you can find it used.
For suggested wiring info: http://www.therangerstation.com/tech_library/volvo_electric_fan.shtml
done a few different electric fan
conversions over the years. I have compiled that info below for those
who might be interested:
ELECTRIC FAN CONVERSIONS
FROM THE PAST
Excuse the photo
quality. This is a very old pic. This is the first electric fan
conversion I did back in 1997
for my 245 Turbo. I also used this same fan for several conversions of
friend's 240s. One in a 240 non-turbo was still going strong and
well more than 15 years later.
<<< The fan depicted at left is from an early to mid-eighties Buick Century, Pontiac Grand Am, Olds Cutlass, or other General Motors mid-sized car with FWD and 4 or 6 cylinder. It is made by AC Delco and is designed to be the primary fan for the car it originated in. This fan should be plentiful in self-service auto salvage yards and should cost between $20 and $30.
Dimensions for this fan are as follows:
Height and Width: 17 inches at shroud edges
Depth at shroud housing next to motor: 3 1/8 inches
Depth at rear of fan motor: approx. 4 1/4 inches
Fan blade diameter: 14 inches.
|<<< A 16 inch diameter fan in the same version can also be found in some of the GM 6 cylinder cars. The outer dimensions will be the same. This is important because this shroud is a pefect size to fit directly onto the typical Volvo 240/740 radiator.|
<<< All four of the original plastic mounting ears on the shroud need to be removed for fitment to a Volvo radiator.
A hacksaw or sawzall does just fine here. In this photo the ears have already been cut off, but I left them next to the fan so you could see where they came from.
Since this fan will be mounted to the
radiator, you'll need some mounting hardware. The simplest method
I found is with some 2 inch sheet metal screws, washers and these funny
little sheet metal nuts.
The screws I used were the counter-sunk
type with some counter-sunk finishing washers. Most any will work
photo shows an existing hole in the top flange of the radiator.
All Volvo radiators will have these holes for mounting of the original
fan shroud. The sheet metal nut can be used here. You will
then need to drill a small hole in the GM fan shroud directly over the
original hole in the radiator.
The plan is for the new fan shroud to be fastened to the radiator by four sheet metal screws, two at the top and two at the bottom. You may need to drill the holes in the bottom radiator flange.
make this fan work in your car, you have several options. You can
purchase an all-in-one fan controller with a temperature probe that
goes into the radiator fins. You can use a coolant sensor mounted in
radiator if it has one.
For my 8 page assortment of relay wiring diagram options, including two-speed circuits, click here (pdf file).
Volvo 940/850 15 inch Fan
(NOT RECOMMENDED FOR HOTTER CLIMATES)
For my 8 page assortment of relay wiring diagram options, including two-speed circuits, click here (pdf file).
|<<< This fan is about 4 inches deep from the end of the motor to the furthest point on the front of the fan. The fan shown in the far left photo has been removed from the original fan shroud. One cool thing about this fan is it simply unbolts from the original shroud. No cutting or chopping needed. After it is removed, you'll find that it is about 17.5 inches across at the outer ring, which is why is fits so well into the Volvo RWD mechanical fan shrouds, which have 18 inch openings . The actual fan blade portion on this fan is only 15 inches.|
940 shroud is too wide for a
normal 240 or 740 radiator, so I did not use it for this conversion.
people have cut them down to fit.
<<< The shroud used in the photos here is a 240 Turbo (Intercooled) shroud. The inside diameter of this shroud is 18 inches. This particular shroud will only correctly fit the 240 Turbo. It will NOT CLEAR the auto transmission cooling lines in a 240 non-turbo or a 740. Since a shroud normally sits further back in a Turbo Intercooled car (because of the intercooler), some extra work was required to get the fan to sit deep enough into this shroud to clear the water pump. It was a tight fit when done.
Better to use a 740 Turbo Fan Shroud:
I found that a shroud from a 740 Turbo (which can be seen in the Ford fan conversion below) is a much better choice to mount one of these fans inside of. The 740 Turbo shroud, also with an 18 inch opening, may be used in pretty much any 740 or 240 model without any fitment issues.
|<<< And this shroud places the fan closer to the radiator, offering at least 1 inch more clearance from the water pump than a 240 Turbo shroud does. Plus it's a lot less work making it fit in a 240 engine bay.|
OVERALL REVIEW:I used this fan for about a year. I was disappointed.
It did not cool as quickly or as efficiently as I liked. I believe this disapointment was because this 15 inch fan is a bottleneck and the volume of flow through the radiator and out the 15 inch fan opening was small (even at highway speeds) compared to the stock 18 inch fan shroud with a heavy duty mechanical clutch fan. It was easy to see a difference during warm days, on uphill grades, and especially with the A/C on.
>>> For real cooling needs with AC, a mechanical CLUTCH FAN is a better choice by far than this one. <<<
| The above fan
lot of amps upon start up when using the high speed circuit only.
Because I wanted to avoid sudden, hard
current draws to my charging system when this fan came on, I sought out
a high-tech fan controller that offered a "soft-start" feature. I
chose the Delta
Current Control FK-55. This
is an all-in-one controller and it works smoothly, so no relays or
other sensors are needed. When it's time for
the fan to come on, it comes on
slowly and smoothly, beginning with about 20% speed until more speed is
needed. It regulates your radiator temperature by
smoothly increasing or reducing fan speed, instead of on, off, on, off,
like the old school method. Definitely not cheap.
PROBLEMS WITH DELTA CURRENT CONTROL (DCC) CONTROLLERSUPDATE Summer 2012: I'm sorry to report that I can no longer recommend the controllers from Delta Current Control. I had two of them fail after less than 2 years of use each. This makes a $180 controller way too expensive if it can't be reliable. And to make matters worse, the owner of DCC, Brian Baskin, has found it impossible to respond to emails, even if you place an order. When I placed an order for a third controller in 2012 my order went unanswered for 6 weeks. No order status info, no communication, period. Nothing. I had to dispute the purchase with Paypal to get my money back after my order and emails went unanswered for 6 weeks (and yes, my car was down the whole 6 weeks).
Ford Thunderbird SC 17.5 inch Fan (YES!)
WORKS WELL IN HOTTER CLIMATES!
2010 I did this
for my 242 Turbo:
This exact fan is only found in the T-Bird SC (with supercharged
6 cylinder) made in the late 1980's to mid-1990's. The
depth of this unit from the fan motor to the front of the fan is only
inches (a little bit
shallower than the 940 fan). It is
the more common V8 Ford T-Bird fan or
Lincoln Mark VIII fan,
except this version is a little less deep
(from motor to fan) and seem to fit with less room. It is
suggested that these fans will pull an estimated 4000 cfm on high.
<<< The circular portion on the Ford shroud is 17.5 inches across, so after some chopping, as seen in these photos, it fits very well into the 18 inch opening of the Volvo 740 Turbo fan shroud. I sought out this fan because after using a belt-driven heavy duty tropical fan clutch for years in my 242 Turbo, I was spoiled by how great it cooled. I tried the smaller 940 fan above for a while. I was disappointed. It did not cool as quickly or as efficiently as I liked. I believe this disapointment was because the 15 inch fan was a bottleneck and the volume of flow through the radiator was reduced (even at highway speeds) compared to the stock shroud with a heavy duty mechanical clutch fan. It was easy to see a difference on uphill grades, especially with the A/C on.
Here's the Ford fan next to the 740 Turbo shroud that I
to mount it in.
The Ford shroud needed to be cut down,
separating the fan and circular ring that was then mounted into the
shroud. I used a friction cutting wheel to trim the Ford shroud,
which worked ok... not
the best job. A sawzall with a fine blade would work much
better on this plastic.
<<< Here's the in-progress assembly and completed fan. The last pic shows it mounted in my 242 Turbo. This is a two-speed fan, like the 940 fan, except this one is much, much more powerful. The low speed on this fan probably pulls at least as much air as the high speed on a 940 fan. I have read that the high speed on this fan pulls between 35 and 40 amps when running continuously. So I suspect this is NOT a fan for a light-weight charging system. A large capacity alternator (100 amp), heavy cables to the fan motor and a high capacity relay (50 to 70 amp) would be a good recommendation. For my 8 page assortment of relay wiring diagram options, including two-speed fan circuits, click here (pdf file).
|PROBLEMS WITH DELTA CURRENT CONTROL (DCC) CONTROLLERS: I can no longer recommend the fan controllers from Delta Current Control. I have had two of them fail after 2 years of use each. This makes a $180 controller way too expensive if it can't be reliable. And to make matters worse, the owner of DCC, Brian Baskin, has great difficulty responding to emails if he ever responds. And if that's not reason enough, another order I placed in 2012 to replace a bad one went unanswered for 6 weeks. No order status info, no communication, period. I had to dispute the purchase with Paypal to get my money back.|
|There are a few options for controlling a primary electric fan like this. The old school method is using a relay (or multiple relays). Relays are pretty reliable, but electronic temperature switches are not always as good in the long term. I installed one of the above 2-speed T-Bird fans in a friend's 240 many years ago and used I used a Hayden 3654 adjustable fan switch (shown at left. It was about $40 at Summit Racing) to turn on the fan low speed circuit for normal cooling needs. Typically I would set a controller at 180 to 190 degrees F, depending on the coolant thermostat being used. Then for this installation I used a separate heavy duty 70 amp relay to trigger the high speed circuit, which was then wired to a standard Volvo on/off temp sender in the radiator (outlet side). This temp sender was there to trigger the high speed if the outlet temp exceeded approximately 210 degrees F, which would happen as a failsafe if the Hayden fan switch failed. I also put an override switch on the dash to turn on the high speed circuit manually if needed. This type of installation functioned well in hot SoCal summers using the A/C for many years, but of course the Hayden controller evenually failed after a number of years and the engine was saved by the failsafe design.|
The photo at left
is the Flex-A-Lite 33054 "Variable"
Speed Controller. At time of writing this, Flex-A-Lite made
these in 35 and 45 amp
versions. The 33054 is the heavy duty 45 amp
version, designed to run multiple fans if needed. The important part about using a controller
like this is that it supposedly uses soft
start technology. Flex-A-Lite also make less
expensive controllers that don't have variable speed or soft
start. I bought this 33054
from Summit Racing for about
$100 and it was in use in my black 242
Turbo (installed summer of 2012) with the big Ford fan shown
above until it failed in 2016. It was wired
to control the fan high speed circuit only.
This controller was more reliable (lasted longer) than the Delta controllers that failed. After installing it, I discovered that this fan controller is not really a true variable speed controller. This controller uses a probe in the radiator fins and when the set temperature is reached, it will turn the fan on at 60% power (set point is adjustable from 160 to 210 degrees F). If the radiator temperature increases more than 10 degrees above your set temperature, the fan switches to 100%.
So the reality is this controller is a 2-speed controller, instead of a true variable speed controller.
That was a big disappointment to me, since the big Ford fan can cool quite well at low speeds (maybe 25-30%) under light load and this controller can't do that. This controller will also operate your fan(s) for up to 30 seconds after shutting off the car if it reads a high enough temperature. And of course it has the connections to add the A/C "ON" circuit (turns on at 60% continuous) as well as circuits for a manual override "ON" switch and manual override "OFF" switch if you want. The installation instructions for the Flex-A-Lite 33054 can be seen here: http://static.summitracing.com/global/images/instructions/flx-33054.pdf
FINAL NOTE: I'm a fan of fitting larger radiators, especially when running AC, but there is prior planning needed when it comes to a 240 Turbo. The standard intercooler configuration limits the radiator width to the stock dimension. So if you go wider, you must plan to install a different intercooler so you can route intake tubes around the wider radiator. You can also go with a taller radiator. It's even possible to install a 19 inch tall radiator. Don't believe me? See the following Turbobricks thread: http://forums.turbobricks.com/showthread.php?t=296380 .
In 2012 I decided I wanted a bigger (WIDER) radiator. I bought this one from Griffin and ordered PN 1-55221-X3. It's 26 x 15.5 inches, 2.7 inches thick, has two rows with 1.25" tubes, 1.38" OD hose inlet/outlet (they call this radiator a universal fit "Chevy style"). Price was about $300. It can be ordered without a top radiator cap flange, but I left it on. The cap used is Stant PN 10230 or 10231. I then had aluminum male AN fittings welded on the right side for the expansion tank and turbo feed hoses (I believe these sizes were -6 and -10). Probably the smarter method would have been to have Griffin install those before shipping if they'll do that.
Before I bought the Mark VIII fan below I was still using the Ford fan mounted in a 740 Turbo fan shroud above.
It was not quite wide enough for this wide radiator, but it worked ok for the time I used it.<<< Then in 2014 I bought a new complete fan assembly on eBay for a 1997 Lincoln Mark VIII. The Mark VIII fan assembly is the correct width for this new radiator (after trimming off the four protruding mounting ears), so it fits nicely. Before 1997 these fans were made as 2-speed fans. This one is a 1-speed fan from 1997. The Lincoln Mark VIII fan is legendary. It easily pulls 40 amps at full speed (at 14v) and some reports say it pulls over 4000 CFM. That's more than double the flow of a 940 fan. If you're tired of fans that just aren't enough for your hot climate, like that puny 940 fan above, and you have AC, you might think about this one.
Outer Dimensions: 22 inches wide (without 2.5 inch mounting tabs), 19 inches tall, 5.5 inches deep. Weight: about 8.8 lbs.
Lots more info here: http://forums.tccoa.com/6-general-tech/136722-ultimate-mark-viii-fan-thread.html
NOTE: If I was still using a stock width Volvo 240 radiator I would have cut off the entire outer shroud from the Mark VIII fan barrel and mounted the barrel inside a 740 Turbo shroud similar to the above conversion #3.
|<<< After trimming off the mounting
steel braced frame inside the TOP
of the shroud
to fully support the weight using the top radiator brackets shown
below. Width was
1/2 inch. Then I bought bolts and clip-on barrel nuts
(AKA: U-Nuts) from McMaster-Carr. The bolts were PN 98093A436 M6 x 1mm, 16mm long
with a flange head (see photo). These have a 10 mm head. The barrel
nuts were PN 95210A150 M6 x
1mm made for a panel thickness of 0.8 to 4 mm.
|<<< I used simple 1/8 inch thick steel bar stock for this brace. Typical metal found at your local hardware store.|
<<< Here's the Griffin radiator and Mark VIII fan installed in my 240. As you can see the original style intercooler is gone since it no longer fits and instead I installed an eBay intercooler in front of the radiator with new pipes going around the radiator. This radiator is WIDE and there is barely enough room to keep the battery in the original location, but it still fits.
<<< Here's a bottom view of the Mark VIII fan. Yes, the Mark VIII shroud is taller than the radiator by several inches. This is fixed by adding some aluminum sheet metal to seal the gap. It's securely fastened and then some duct tape added to seal the bottom gap.
<<< I continued using the Flex-A-Lite 33054 Variable Speed Controller that I had previously installled in conversion #3. As I mentioned before, I was disappointed after I discovered that this controller is actually only a 2-speed controller instead of a true variable speed controller. I really would rather have something that begins spinning the fan at 10% or 20% or 30% instead of 60% low speed like this controller has.
Anyway, this controller
MELTED ITSELF IN 2016
on a hot day when I had the AC going and while pulling into a car meet.
So this one is definitely NOT recommended for a large fan.
So here's the Auto Cool III
that I installed in my 242 Turbo in November 2018 to control my Lincoln
Mark VIII fan. It's a 125 amp
PWM fan controller. It's internally fused for 150
This controller can run one or two fans. When running one fan
like I am, the output posts (FAN A and FAN B) are combined as shown
here. The output to my fan then comes from the FAN A post.
It may seem a bit backwards, but these controllers are designed so that the 12v cable from the battery goes directly to the fan positive pole. Then the fan gets controlled by the negative cable, which comes from the FAN A or FAN B posts (or both).
That's a 3 amp fuse I added between the battery and the controller 12v
Here are the input pins on top. Hooking this thing up is pretty
Pins 7 and 8 (those white wires) are for the full speed dash override
switch (labeled F/S for
"FailSafe"). When those two pins are connected together, the fan runs
<<< The AC speed adjustment trimpot is beneath that black cap.
Here's the AC trimpot under that black cap. I used a photo
tachometer to measure fan
blade speed and I set the AC speed at 1500 rpm, which is 75% of
maximum speed of measured at 13.5 volts input.
Here's the default temperature sensor that came with this
controller. This is the one you get, unless you order one of their
optional screw-in sensors. It's designed
to partially slip under the radiator
outlet hose and may be used on any ALL METAL radiator. It's not
recommended for radiators with plastic outlets. This is
sensor I used for my all-aluminum radiator. It comes with a long
wire lead that's wound as a twisted pair.
Or you may optionally choose from a variety of screw-in sensors.
AutoCoolGuy does not offer a push-in sensor probes for radiator fins.
They don't believe in those due to their inaccuracy.
Here's the fan full speed override
I put on my dash. I have seen a LOT of previous fan controllers FAIL
years. Having an override switch is a really good thing, even if
only for nothing but peace of mind. I also added an LED light
that lights up when the fan
is on. It lights up dimly at low speeds and gradually gets
as the fan speeds up. This is also a really good thing for people like
me who have developed cooling fan
AutoCoolGuy has instructions for wiring this LED in their webpage HERE. In those instructions they show the use of a 1.5k Ohm resistor in line with the power wire for the LED. I found that a 1.5k Ohm resistor was not sufficient. My LED was way too bright with that resistor and it really lit up the interior at night. So I switched to a 10k Ohm resistor and the brightness seems about right and won't blind me at night. Who knows? Maybe the LEDs I have are brighter than others.
If you have any feedback or comments, please let me know: CONTACT
the deal with BUZZ or No-BUZZ mentioned in their webpage?
From what I've learned, there are some fans that are prone to making a buzzing sound when receiving PWN input. AutoCoolGuy describes this as a mechanical problem in some fans which have a blade and armature that's too loose. They said many Asian made fans have this issue, but many Ford or other American made fans do not. There is more info in their site as well as some videos of this buzzing in action. Basically, if you have a fan that does this and it bugs you enough to do something about it, then there are remedies. AutoCoolGuy offers an add-on Buzz Box that can be connected between the controller and fan to suppress the buzzing. They also have a couple of controllers with the extra no-buzz circuitry built into them.
I DID NOT order a No-Buzz controller and my aftermarket (Dorman) Mark VIII fan does not buzz. So I guess I have a pretty decent fan.
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