Detailed Instructions on how to
install fans in your engine lid
on a 1993 MR2 Turbo.
NOTE: this proceedure will work for most MKII turbo or N/A car.
WARNING: you will be working with a LIVE 12v circuit, you may want
to disconnect the NEG side of the battery before starting
this proceedure. But be warned, if you have set your
stereo anti-theft code, make sure you clear it BEFORE you
pull the NEG battery lead.
Tools Used:
10mm 1/4 socket
10mm openend boxend wrench
short 1/4 drive extension
pair of wire cutters
#2 phillips screw driver
25 watt soldering iron
small amount of solder 60/40 resin core
4 10lb barbell plates, or perhaps some large
heavy books.
small hack saw
small metal file
Parts Needed:
Two 10 Inch pusher SPAL fans from RacerWholesale
PH: 1-800-886-7223
25 feet of #10 gauge hookup wire
10 feet of #14 gauge hookup wire
two (minimum) 10 amp 12v SPST relays
1amp 1000piv rectifier diode. If you can't get a 1000piv
then 600piv will do. (piv = peak inverse voltage).
a 10 MFD NON polarized electrolytic or a
.1 MFD mylar or ceramic
If you get the electrolytic then make the voltage as
high as you can say 50 or 100 volts.
You can get as high as 200 volts for the mylar or ceramic.
Some #16 or #18 and #10 sized electrical eyelet lugs to
connect the hookup wire.
3M Super Strong Automotive Attachment Tape Cat. No. 03609
NOTE: I used the 3M tape to tack down the wire, if
you have a better method, please use it.
3M surface cleaning solution
GOOP Automotive glue
rubber self sticking electrical tape.
Stanley screen door stiffening rod.
short 6mm screw and nut.
NOTE: for the relay, you can go with several different
combinations, I used a single 30 amp relay, but you
could use a double relay with a lower rating, for
example a dual 10 amp relay could be used.
You should be able to get a 12volt 10amp DPDT
(double pole double throw) at Radio Shack for about
$10 Note that most of the ones sold at Auto parts stores
are single pole relays. You could go with two single
pole relays if you can find nothing else. If you get one
from Radio Shack, it will probably not be a sealed kind
so you would need to put some RTV or something around it
inorder to seal it against getting wet.
PROCEEDURES:
You will first need to mount the fans in the engine lid, so we will
first remove the engine lid. First remove the holder bracket that
holds the temperture sensor for the stock fan, if you haven't already.
There are just two screws holding it in place. Since you really do
not need this sensor, and the addition of these fans will prevent it
from working normally, then you do not want it in the circuit.
I simply cut the whole thing off, as far down as I could reach as the
wire harnes goes over to the drivers side not far from the gas fill
pipe. The sensor does not need to be physically connected for the
circuit to work the way you want it to. Or if you want to properly fool
the circuit into thinking that the sensor is still there, then you could
solder a small 300 ohm 1/8 watt or 1/4 watt resistor across the ends of
the wire. This would fool the circuit into thinking that it is always
above 144 degrees in the engine compartment, and tell the fan circuit
to activate that circuit all of the time.
Of course this makes the assumption that you are NOT going to use the
stock circuit to power the engine lid fans. Remember that the stock
engine cooling fan is only pulling about 5 amps, the two engine lid fans
will pull more than twice that, so you would far overload the circuit if
you tried to use the engine lid fan power to run the two engine lid fans.
NOTE: it helps to have two people to remove the engine lid but it
can be done by one.
After having removed the temp. sensor in whatever manner you desire, then
using a 10mm socket and small 1/4 drive, remove the four screws that hold
the engine lid in place. You will want to lay the engine lid down on a
nice soft flat surface where you can work on it. Be careful not to
scratch the finish, and remember that this is made out of a composite
material, so be careful, you can break it.
After having laid the engine lid down on a soft flat surface, then using
a phillips screw driver, remove all of the screws that hold the inside
metal liner in place. Be careful when doing this, as these screws go into
the composite material, and it will crumble under a lot of pressure.
After removing the inner metal liner, you will want to clean out the
holes where the screws were. I used some compressed air to do this,
you could just turn it over, and carefully dump out any debris.
Surface preparation in this case will be very important, so one of the
first things you will want to do is position the fans where they will
be perminently placed and see where this is on the engine lid.
I used a carpenters pencil and marked the area where the fan rests
on a cross member on the lid. This will give you a guide line.
I used some 3M surface cleaning solution and a clean towel or rag.
Also clean the area on the outside rim of the fans to make sure that
the surface is clean. Avoid touching this area after you have cleaned it
remember your fingers and hands are loaded with oils.
If you don't have any of the 3M cleaning solution, then you could use
some isopropyl alcohol.
I positioned the fans so that the electrical cords pointed down,
meaning down from where the latch hook is. Considering that the top of
the lid is, as it swings on the hinges, the part furthest away from the
hinged end, and the bottom of the lid being the hinged end.
If you position the wires so that they point down, then it will be much
easier to hook up the rest of the wiring later.
MOUNTING THE FANS ON THE ENGINE LID
-----------------------------------
As I said before, surface prep is a very important thing to make sure
that when you get the fans set in place they stay there.
After you have placed the fans, and you know where you want to position
them, then clean the fan edge and side, and the areas where the fan
touches the engine lid.
GLUEING THE FANS IN PLACE
-------------------------
I used GOOP Automotive glue. As this is some fairly powerful stuff
then use it sparing, don't go overboard with gluing the fans down
because you will need to remove them some day.
But on the other hand, don't use to little glue either.
The GOOP Automotive glue is clear, and can be used as a contact
cement. Read the instructions on the glue carefully.
Also make sure that you have a good fan running, and have air movement
because this glue contains methylethylketones, which can literaily
fry your brain. So be carefull. HAVE GOOD VENTILATION.
I used a cut off piece of a large tie wrap to help spread the glue
on the engine lid and on the edge of the fan. The instructions on
the glue say, spread a layer of glue on both surfaces and allow the
glue to set for 2 to 10 minutes, depending on how warm it is, the
warmer the less time.
Then carefully position the fan and then press it down in place.
I used two 10 lb. barbell plates and set them on top of the fan to
keep a constant pressure on the fan. Do this for both fans and then
let them set for at least three or four hours before moving them.
After that time, you will then be able to remove the barbell plates
and reinstall the engine lid on the car.
REMOVING THE FANS
-----------------
OK, so you say, now that I have used this glue from hell, how do I
remove these fans when they need to be replaced. My answer is
piano wire. Get the thinnest piece of piano wire you can, and using
two small pieces of dowel rod, mount both ends of the piano wire
in the each of the dowel rods to make handles. Then position the piano
wire around the outer rim of the fan and pull, and the fan will be
cut loose. Then it is a matter of scraping and cleaning off the old
glue, and put on a new fan in the same manner as described above.
WIRING
------
You will need to refer to my section in installing the single intercooler
fan for the details of the key switchable source that I used inside the
#2 fuse box. You can tap that source to switch the relay of course
unless you wish to put in a switch. I have also been thinking of
moding one of these auto start remote units so that I could turn the
fans on with a remote, and not have to run a wire through the firewall.
Specifically how you hook them up is really up to you, I can give you
some general guide lines, and will explain how I hooked mine up.
Basically it goes like this. I purchased a 30 amp relay from Alied
electronics. Just about any SPST relay will work, you don't have to
use a DPDT, (double pole double throw) relay. Since speciality relays
may be difficult to find, you could use a relay or two relays for lights
most auto parts stores have those types of relays, and most will handle
20+ amps. If you do decide to go this route then may I suggest that you
use two 20 amp relays to turn on the fans, verses using one larger relay.
It may provide a little more flexability in their operation.
But which ever way you choose, will be up to what your weather conditions
are, and I suspect many other factors as well.
Once you have choosen a specific setup for the relays, then using my
other detailed instructions on how to install the single intercooler
fan, hook up your key switchable source from the #2 fuse box. Or you
could also run a wire into the engine compartment through the firewall
if you want to use a seperate switch to turn on the fans.
In hooking up the relays, you need to do two things to the relays.
First you need to hook up a high PIV diode across the activation coil
on the relay. This will prevent the high voltage inductive kick back
from going down the power supply wire, and into some other circuit
where you don't want it. On the relay, there is a NEGATIVE, and a
POSITIVE wire that power the relay. On the diode, there is typically
a band that marks the Cathode or NEG side of the diode.
The diode gets wired on to the relay across the coil in reverse polarity.
Meaning that the banded side, the Cathode (NEG) end of the diode goes
to the positive side of the coil, and the positive side of the diode
the NON banded side, goes to the negative side of the coil.
The reason for this is that the counter EMF that the coil produces is
in reverse polarity of the applied voltage. So inorder to shunt it out
the diode must be wired on to the coil in reverse polarity. If it wasn't
then the first time you applied power to the relay, the diode would turn
on try to shunt all of the current, and burn up all in about
10 miliseconds.
The second thing that you need to do is to put a cap across the contacts.
This capacitor will act like a shock absorber, and will help shunt away
the large arc starting current when the fans initially turn on.
This capacitor needs to be as large as physically possible. Meaning that
a 1 mf non-polorized electrolytic will be quite small, and about the
size of a pencil eraser. The mylar, or other type of non electrolytic
caps will tend to be very much larger, unless you have a special source.
I believe you may even be able to find a non-polar electrolytic over
at Radio Shack, they are used specifically for tweeter cross over systems
and should do the job nicely, and not cost much.
The capacitor is wired directly across the contacts. Since it is
a non polar electrolytic, it doesn't matter which lead goes where.
This is an important addition so as to keep the contacts from being
worn down prematurely.
Of course if you purchase two relays then you will need two diodes and
two capacitors, one diode and one cap for each relay.
If you purchase a double pole double throw relay then you will only need
one diode but two caps for that relay, one diode for the coil, and one
cap for each set of contacts.
Ascii art is not one of my better achievements but here goes:
relay coil
Ground--------oCCCCo--------------KEY swich source from #2 fuse box.
FAN------fuse--o o-------------Main Power Feed from #2 fuse box.
\
\ <--- relay contacts.
NOTE: the fuse can go on either side of the relay contact.
|------>|------| <--- diode across relay coil.
| |
Ground----o----oCCCCo----o------- + side KEY switch source.
--o------o o-------o------
| \ |
| \ |
|___________||______| <-- Non polar cap across relay contacts.
HOOKING UP THE WIRES
--------------------
Once you have picked a method of relay that you are going to use then
you will need to find a position to put the relays so that they can be
hooked up. On the 1993 MR2, there is a good place up by the side of
the strut tower on the drivers side, that is under the side trim cover
piece. This is a good place to mount the relay as it is out of the
direct path of rain, and even engine cleaning if you are careful.
You may want to make sure of one of two things, either purchase a
totally enclosed relay, ie.(hermetically sealed), or purchase a little
less expensive standard relay, and seal it yourself. The hermetically
sealed ones may be a little more difficult to find, although some
of the heavy duty light system relays are supposed to be hermetically
sealed, so you may want to go this route and check your local auto
parts store, and check out their relays used to switch lighting systems
in most cases you can purchase a relay seperate from the entire
lighting system, and I know I have seen them for sale in JC Whitney.
Although I might question the quality.
Also the drivers side strut tower is not far from the #2 fuse box where
the key switchable source and power source for the fans is located.
In my detailed instructions for hooking up the intercooler fan I give the
details of where I tapped the source for the main power, not the key
switchable source power, for the fans. There are two sources that you are
dealing with in the #2 fuse box, one is the key switchable source which
is used to power the relay ONLY. The other source is the main cables
from the battery + side that feed the alternator. This is the source
that you are going to tap to power the FANS only.
I used #10 hookup wire, for the FAN power source. You can use #16 or
even #18 for the KEY switchable source to power the RELAY coil.
Please make sure that you understand the difference between these two
power sources.
Afer you have picked a place to mount the relays, then using either some
isopropyl alcohol or you could use the 3M surface clean for the 3M tape
product. The 3M surface cleaner is made specifically for the double
sided 3M sticky tape to ensure that it will have maximum adhesion but
it is also the most powerful, so if you decide to use it, be careful
as it may damage your paint if you accidently get it somewhere where
you don't want it.
Prep the surface on both the car, and clean the surface on the relay
that you are going to stick down. Remember surface prep is very important
and will make the difference. I assure you, if you prep the surface
properly and then stick down this 3M tape, IT WILL STICK! So make sure
that you have the relay where you want it before you stick it down.
NOTE: I am not much of a one for drilling holes when I really don't
have to, so that is why I suggest using the 3M tape, it is more
than sufficient, but for those that are more adventurous
then if it is appropriate, drill a hole to mount the relays.
NOTE: you can use one of two different methods to insulate the wires
I like to use shrink tube when ever possible, it is neater and
looks better. But if you use tape, I would suggest using a self
sticking rubber tape rather than regular black electrical tape.
Now once you have your relays stuck down in place, you are ready to do
the wiring. Find the key switchable source, and tap a wire there using
my instructions outlined in the installing an intercooler fan.
After you have a wire comming out the bottom of the #2 fuse box then
using small pieces of the 3M double sided tape, stick the wire to the
side of the strut tower and route it up to where the relays are mounted.
Judge what the proper length of the wire should be for the KEY switchable
source, using either #16 or #18 hookup wire, and using a small 25 watt
soldering iron and a little solder, solder the wire in place on the
relay coil. Remember that it really doesn't matter which side of the
coil on the relay is + from the #2 fuse box KEY switchable source and
which side of the relay is ground, but remember when you choose this
+ and - side, that you get the shunt diode on with the correct polarity.
As you can see there is a chassis
ground source very close on the drivers side there next to the strut
tower. So hook up one side of the coil to the KEY switchable source
and run a small ground wire over to the other side of the coil.
At the same time remember that you need also to be hooking up the diode
across the coil, in REVERSE polarity to the source voltage. So that
you make sure that the BANDED side (cathode side) of the diode goes
to the + side or key switchable source side of the coil. And that the
+ positive side of the diode goes to the ground side of the coil.
Remember that the diode must be reverse polarity to the applied voltage
to the coil or you will just burn up the diode the first instant you
apply power to the relay.
If you have two relays then make sure you hook them up the same way.
To make it easier you can run short pieces of wire between the two
relays, and then run the main wires over from the #2 fuse box, that way
you will not have to run two sets of wires over from the #2 fuse box.
This will save a lot of time and headache as there will not be much space
when routing the wires out the small hole in the bottom of the #2 fuse
box. Remember from my other instructions, you will NOT have to drill
any holes in the #2 fuse box to route the wires, as there will be
sufficient space to route them out the bottom of the fuse box where the
stock wires come out already. I found that sparing use of a little
silicone like Wesleys Black Magic on the ends of the wires helped them
slide through.
NOTE: also, at least on my 1993 MR2, where the main cable comes out of
the #2 fuse box, you can slide the wires in there also which may be
a little easier.
You will need to for the fan power source, solder on a #10 electrical
eyelet lug on the wire so that you can attach it to the stud that the
main power cables are attached to in the bottom of the #2 fuse box.
You may want to take a good look at the electrical stud in the bottom
of the #2 fuse box so that you can properly gauge the size of the
connector lug you will need. Remember that these electrical lug
eyelet sizes come in many different sizes of eyelet for the same sized
cable ie.(#10). So make sure that you pick the right sized eyelet
so that it fits the stud properly in the bottom of the #2 fuse box.
Again if you are using two relays then position them so that it makes
it easier to hook up the wiring. You will want to make up some small
jumpers that jump between the two relays to hook up the KEY switch source
and the main FAN power source so that you only have to run two wires
from the #2 fuse box. Chassis ground is already outside.
As you are hooking up the relays make sure you observe polarity when
necessary, especially for the diodes that go across the relay coils.
Also very important, make sure that you put a fuse in the + side of the
fan power source. Position it so that it is easy to get at.
I found that the new blade type fuse holders were not very good, and
I almost started one on fire because the contacts were not making good
contact in the fuse holder, and started arcing. The thing got so hot
that it partly melted the fuse holder and part of the fuse.
So I wound up actually soldering the fuse into the circuit. It was the
only way I could ensure that the fuse and wires were making good
contact. You may also try a cartridge type of in line fuse. This should
work OK for a two relay setup where one fan is run from each relay.
As I said before, this may work out better because it splits the source
current in half, and makes it easier on each relay.
The minimum current carrying capacity for each relay should be 10 amps.
This will ensure that the initial rush current will not fry the contacts
and weld them together.
Also make sure that you solder all of your lugs on, and solder all of the
connections to the relays. You could also if you want to use relay
sockets for the relays, so that they can be unpluged and replaced. If you
do so make sure that you make all of the connections to the sockets and
not to the relays themselves.
So you need to run two wires out of the #2 fuse box, one to the KEY
switchable source #16 or #18 wire and one larger wire #10 wire to
the main power feed that goes to the alternator which is the stud pair
in the bottom of the #2 fuse box.
Route these wires out the bottom of the #2 fuse box where the hole is
that the stock wires come out, and use some silicone grease or wesleys
silicone to help you feed the wires out the bottom of the #2 fuse box.
Once this is done then clean the surface of the strut tower where the
wires will be routed and use some small pieces of the 3M double sided
sticky tape to hold the wires in place.
Then use the ground wire that is already under the side trim pannel
you may want to clean up the paint where the bolt actually goes into
the chassis, this will ensure a proper ground. You can use this same
ground point for the ground side of the fans, as well as the ground
side for the relay coil.
It is fairly easy to see where the wires will go. Remember that if you
are using two relays make sure that you run one wire over from each of
the two fans + (positive) side wires, one to each relay contact.
On a single pole single throw relay hook the + lead from the fan to
one side of the contact, and the + main feed wire from the #2 fuse box
to the other.
NOTE: some relays have the ground or negative side of the coil contact
as the body of the relay. If you have one of these metal relays
then don't let it confuse you. It will have to be grounded well
in order for it to work properly.
TESTING PHASE
-------------
Once you have all of the wiring done, and you have DOUBLE checked your
wiring, then give it a test. Hook up the Negative battery terminal
and click the key over to ON and see if the fans come on, which they
should.
If something isn't working, then turn the key off, and check over the
wiring again, and find out what is wrong.
LID PROP ROD FABRICATION
------------------------
Now you will also say that there is no way for you to prop open your
engine lid since that went when the inner metal liner was removed.
So here is what I did. I bought a Stanley screen door stiffening rod.
This is a long metal rod that is used on screen doors to keep them
square.
Or you could make one yourself out of a metal rod, but the Stanley
screen door rod already has the flange end formed with the hole in it
so this makes it very easy to fashon the prop rod out of it.
Also look at the WEB site under the Who's Who section for pictures of
this prop rod. On the 1993 MR2 and I believe on the 91 and 92 models
there is an extra threaded hole in the engine lid. I mounted the rod
on the drivers side so that the rod extends down from the pivet hole
to rest in the top of the screw head that holds the side trim piece
on.
Basically all there is to it is to measure the size that you want the
rod, ie.(how far open you want the engine lid when the prop rod is in
place), and then cut it to size. A small hack saw should do the job.
I then used a small metal file and rounded off the end so that it would
fit nicely in the head of the bolt that holds the trim piece on.
In case you don't have a bolt with a concave top in it, then I would
suggest that you purchase a new bolt, and using a drill bit that is
say about 1/4 to 3/8 inch in size, drill a concave depression into
the top of the bolt. This will give the prop rod a place to set.
Then I used a 6mm or 8mm bolt to secure the flat flang area of the
prop rod to the engine lid. There is an unused threaded hole in the
engine lid on the drivers side that you can use for the pivot point
of the prop rod. Along with the bolt I put a nut on the bolt and then
sandwitched the flange part of the prop rod inbetween the bolt head
and the nut. This is so you can tighten the bolt in place, but at
the same time adjust tightness on the prop rod so that it can easily
pivot on the bolt. I adjusted the pivot action so that there was some
degree of friction such that the prop rod did not pivot freely
under its own weight, that is so when you swing it up to close the
engine lid, it will not freely pivot when the engine lid is closed.
After the prop rod is in place you will need to bend it at the flange
so that when it is in place the end of the rod will come down into
the concave part of the trim piece bolt head. Be careful when bending
so as not to bend to far, and not to put any undue pressure on the
bolt or the engine lid mounting. You may want to remove the prop rod
bend the flange and then put it back on and check for proper angle.
RUBBER BUMPER INSTALLATION
--------------------------
Now you will need to remove the two round rubber bumpers that are used
on the engine lid to level the lid on both ends. These will have to be
trimmed slightly and then glued down to the rear lip of the engine compartment.
I trimmed about 1/8 inch off one end of the rubber bumpers to make them
just slightly smaller so that when the engine lid is closed they will
hold the lid ends at the right height.
If you look at the rear lip of the engine compartment, you will see two
clear round plastic patches that are used as bumper pads. This is where
the rubber bumpers touched when the stock lid was in the closed position.
You will be gluing the bumpers down to the same position where these
pads are located.
I first removed the pads, because you don't want to glue the bumpers down
on top of the pads. Then using the same automotive GOOP glue you used
to glue the fans in place, put a thin layer of the GOOP glue on one end
of the rubber bumpers, and a thin layer of GOOP down on the lip of
the engine compartment where the bumper is going to set.
Remember that surface prep is an important part. So as you did with
the fans, make sure that you clean the surface where the bumpers will
be glued down, so that they will stick properly.
Following the instructions on the GOOP tube, allow the glue to set
for a few minutes, and then press the rubber bumpers down in place.
Then test the lid for closure.
You may need to slightly adjust the engine lid latch so that the lid
closes properly.
--
+ ------------------------------------------------- +
+ +++ N E C +++ +++ A M E R I C A +++ +
+ ------------------------------------------------- +
+ Marc L. Summers System Administrator +
+ 3100 N.E. Shute Road Hillsboro Oregon 97124 +
+ PH: 1-503-681-3338 FAX: 1-503-681-3304 +
+ Email: marcs@tdd.hbo.nec.com +
+ ---------- Sic transit gloria mundi. ------------ +
+ --- "Thus passes away the glory of the world." -- +
+ ------------------------------------------------- +
