I began tinkering with
electric primary fan conversions in Volvo 240s back around 1997 after
having some poor success keeping my '84 245 Turbo from
running too hot during warm 100+ degree Southern California months
using the stock
pulley fan. I then
developed this page in
1999 to share the info I found and I have been updating it on occasion.
will outline some pretty simple and inexpensive primary
fan conversion ideas for the Volvo 240 and 240 Turbo. 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.
conversions, the belt driven mechanical fan and fan clutch is
eliminated, and an electric "puller" fan is mounted in it's place.
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.
ARE OTHER OPTIONS
AVAILABLE? DO I HAVE TO
CONVERT TO ELECTRIC?
The following information was
borrowed from Brickboard posts by Fitz Fitzpatrick
I would recomend reading
posts before starting an electric fan conversion.
The first is a transcript of a discussion with a Volvo Technician at a
local Volvo dealership
and it covers some material on an electric fan conversion (and reasons
not to do it). http://www.brickboard.com/RWD/index.htm?id=639874Shop talk with a Volvo
Should you still decide to go
ahead with the conversion, this second link covers a lot of relevant
information and some material on how to perform an electric fan
conversion using a GM
puller fan (behind the radiator, towards the engine), but much of the
information is relevant to a pusher fan as well. http://www.brickboard.com/RWD/index.htm?id=692614
Electric Fan info for GM 4-cylinder engines.
For any electric fan
installation, make sure that
fan is capable of turning itself on reliably if your engine starts to
Since the red block engines found in our 240 Volvos
use an iron block
and an aluminum head, the expansion rates of the metals are different.
At overheating temperatures, the expanding head will literally push
against the end head bolts (at cylinders 1 and 4) and warp itself,
bowing upwards. This warping will cause a loss of compression, head
gasket failure, and an expensive repair bill to have the head machined
(assuming it is still within correctable tollerances). Before you
chastise Volvo for using an aluminum head, they chose it with a reason.
Valve temperatures are greatly reduced by the thermal conduction
properties of the aluminum head, and given proper cooling system
maintance, the head should last as long as the block.
With that said, there are two
reasons for performing an Electric Fan Conversion. The FIRST is to
reduce the engine drag at highway speeds. In theory you should gain
horespower at highway speeds. (Remember, the fan does not match
engine RPMs unless your radiator is overheated. The viscus clutch keeps
it at lower speeds when additional cooling is unnecessary.)
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 fan can shorten its potential service life.
Here's a YouTube video with dyno testing for different types of
mechanical fans. Different mechanical fan react quite
differently, however this will offer you some perspective.
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 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 were inferior in
compared to a heavy duty
tropical fan clutch, except for the huge Ford
fan at the bottom of the list, which
so far is only equal to it. More info on the Heavy Duty Tropical Fan
Clutch can be
found in this page: http://www.240turbo.com/TropicalFanClutch.html
FAN RELAY Basics. I get a fail number of emails
about this relay. Lots of people use it to control 2-speed fans
because it's cheap (if you buy it used or get it from a salvage
I also get lots of questions about where to find the
connector plugs. I don't have any sources for the two
outside plugs, but I can tell you the male terminals for those
two plugs are .375 inch in size.
<<< So if needed you may simply use .375 female
terminals and insulate them with heat
shrink tubing. These are available in my page here: http://www.240turbo.com/blackvinyl.html#.375inchterminals.
For suggested wiring diagrams I suggest
searching "volvo fan relay." You'll find a number of suggestions.
done a few different electric fan
conversions over the years.
I have compiled that info below for those who might be interested:
FAN CONVERSIONS FROM THE PAST
Conversion #1 (1997)
GM 14 and 16 inch Fans
RECOMMENDED FOR HOTTER CLIMATES)
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.
depicted at left is from an early to mid-eighties Buick Century,
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.
this fan are as follows:
Height and Width: 17 inches at
Depth at shroud
housing next to motor: 3
Depth at rear of fan motor: approx. 4
Fan blade diameter:
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
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
A hacksaw or sawzall does just fine here. In this photo the ears
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
<<<Here we have the new fan mounted
This assembly can now be placed in the car as one unit and mounted as
radiator is mounted.
Volvo 940/850 15 inch Fan
(NOT RECOMMENDED FOR HOTTER CLIMATES) 2009
Conversion for my 242: This is a very
fan used in many conversions. It's found in 1992 and later Volvo
940 and 960 models as well as all 850s. There is a similar fan
found in the S70 and S80, however the S80 models I have seen feature a
more compact motor. I'm not sure if it's capacity is less.
All of these fans are two-speed models,
with low speed being about 50%
of high speed. The motor will have three wires; one ground and
hot wires (one for low and one for high). A two-speed
circuit may be used when you install one of these or you may use just
the high circuit only. My
installation used the the high speed only.
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
shrouds, which have 18 inch openings .The
blade portion on this fan is
only 15 inches.
The 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
(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
I found that a shroud from a 740
be seen in the Ford fan conversion below)
much better choice to mount one of these fans inside of. The 740
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.
I used this fan for about a year. I was disappointed. It
quickly or as efficiently as I liked. I believe this
disapointment was because the 15
is a bottleneck and the volume of flow through the radiator
and out the 15 inch fan opening was reduced (even at highway speeds)
compared to a stock fan shroud
a heavy duty mechanical clutch fan. It was
easy to see a difference on uphill grades, especially with the A/C
needs with AC, a mechanical CLUTCH FAN is a better choice by far than
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) CONTROLLERS
Summer 2012:I'm sorry to report that
I can no
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
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
in 2012 my order went unanswered for 6
weeks. No order status info, no communication, period.
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).
Instead I bought a Flex-a-Lite
variable speed controller. See the below Ford fan conversion for
more info on that.
Ford Thunderbird SC 17.5
inch Fan (YES!)
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.
on the Ford shroud is 17.5 inches across, so after some chopping, as
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
tropical fan clutch for years in my 242 Turbo, I was spoiled by
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
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 is the Ford fan next to the 740 Turbo shroud 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.
in-progress assembly and completed fan. The last pic shows it mounted
in my 242 Turbo. This is a
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
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
options, including two-speed fan circuits, click here (pdf file).
PROBLEMS WITH DELTA
CURRENT CONTROL (DCC) CONTROLLERS:I can no
recommend the fan controllers from Delta Current Control.
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
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.
are a few
decent 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
temperature switches are not always as good in the long term. I
installed one of these 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
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 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
(outlet side). This temp sender would trigger the high speed if the
temp exceeded approximately 210 degrees F. I also put an override
switch on the dash to turn on the high speed circuit manually if
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 several years.
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 uses soft
start technology. Flex-A-Lite also make less
expensive controllers that don't have variable speed or soft
start. I bought the 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.
that this fan controller
is not really quite a true variable speed controller, but it was more
than the Delta controllers I used to have. It uses
in the radiator fins and when the set temperature is reached, it will
turn the fan on at 60% power (set point 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 only a 2-speed controller, instead of a true variable speed
controller can only turn on a fan at either 60% or 100%.
That was a big
disappointment to me, since the big Ford fan can cool quite well at low
speeds (maybe 20%) under light load and this controller can't do that.
This controller will also
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
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 to add these switches. The installation instructions for the
Flex-A-Lite 33054 can be seen
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
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
. Good stuff!
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
(I believe these sizes were -6 and -10). Probably the smarter method
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
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
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
and you have AC, you might think about this one.
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
mounted the barrel inside
740 Turbo shroud similar to the
above conversion #3.
<<<After trimming off the mounting tabs,I
steel braced frame inside the TOP
of the shroud
to fully support the weight using the top radiator brackets shown
simple 1/8 inch bar steel for this brace, typical stuff found at your
local hardware store. Width was
1/2 inch. Then I bought bolts and clip-on barrel nuts
(AKA: U-Nuts) from McMaster-Carr. The bolts were PN 98093A436M6 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.
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
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
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
<<< 2016 UPDATE NOTE:
new, better fan controller has become a reality.
The Flex-A-Lite died in the summer of 2016 (while pulling into a car
meet), so then I decided to build
my own custom 4-speed
fan controller using reliable relays to control my Mark VIII fan.