Smiths heaters available from the Land Rover factory before about
1968 were totally inadequate for Canadian and Northern United States
winter weather. To address this a heater was developed for Land Rover North America by the Eton company in Canada. This heater was offered exclusively in North America as a dealer option starting sometime during late Series I production, continuing until around 1970 . There seems to be a few years
during which the Kodiak Mk IV heater overlapped the Smiths fresh
air heater. Almost
all fresh air heaters used on series III Land Rovers were Smiths heaters installed at the Land Rover factory.
Over the years there were four versions of the Kodiak fresh air heater which drew fresh air from one of three locations on the truck. They were the Kodiak MKI through MKIV. I have yet to pin down the years of manufacture but it appears that the Kodiak MKI was in production from around 1956 or 57 through 1958 or 59.Then the MK II was only in production for a year or two followed by the common MK III that was in production throughout most of the 1960's. The MK IV appears to have gone into production just before Land Rover introduced their fresh air Smiths heater. The Kodiak MKIV was manufactured by the Hupp Corp.,Mobile Products Division in Cleveland, OH. The Hupp Corp was formally the Hupp Motor Car Corp., manufacturers of the Huppmobile.
The reason that the years of manufacture are so hard to pin down is that the heaters are a dealer installed option and each dealer had their own stock which got used until used up. So one dealer could still have MK I heaters in stock to install on a new Land Rover while another dealer may have run out of MK I's and be installing MK II heaters on the same year Land Rovers The
heater was available as either a dealer installed option or as
a dealer sold kit that an owner could retrofit onto their own Land
such there are some variations between vehicles as to how the heater
was installed and some older Land Rovers were retrofitted with
newer versions of Kodiak heaters.
4X4 web site
does a good job of illustrating the different Kodiak air distribution
Some people consider the after market Rovers North Mt. Mansfield heater to be the best heater upgrade so I thought I would give a BTU comparison. The Mansfield heater is rated at 20,000 BTU and the common Kodiak MK III is rated at 17,500 BTU. There is a 2,500 BTU difference betwen the two. Modern aftermarket 4X4 heatrs operate in the 25,000 to 28,000 BTU area but take a bit more effort to adapt to a Series Land Rover.
The Kodiak MK I heater
The Kodiak MK I fresh air heater was introduced around 1956 or 1957 for the Series I Land Rover and used in the early Series II Land Rovers. These heaters draw their air from the front inner wing panel just forward of the radiator bulkhead.
The fresh air intake is fitted with a screen and hose mounting
flange (nor shown). The intake
tubing is routed inside the top of the wing above the front tyre to the fan
housing. There are a couple of large metal hoops connected to underside of the
top inner wing panel to hold the long ducting tube in place.
The photos used to illustrate the Kodiak MK I are from a 1958 Series II Land Rover and are courtesy of Rich Lambert.
Manor components of the Kodiak MK I heater
Air distribution box for the Kodiak MK I heater.
The Kodiak MK II heater
The Kodiak MK II heater was only in production for a year or two. The fresh air intake is located on the lower right corner of the radiator bulkhead. The intake hole is fitted with a screen and hose mounting
flange. The flange is held in place on the radiator bulkhead with
two screws. The air intake hose is routed under the battery and air cleaner shelves to a heater core intake box on the right upper bulkhead.
The series of Kodiak II heater pictures come courtesy of Mike Flahault. Taken while restoring his 1960 Series II Land Rover.
NOTE: the originla metal holding straps had rusted away so the replacement intake hose is held up with nylon straps.
Thank you Mike for the use of your photos.
The Kodiak MK III heater
badge picture courtesy of Mitch Stockdale
The Kodiak MK III heater was in production through most of the 1960's and is by far and away the most common version. The MK III is the first Kodiak heater version to draw fresh air from the upper rear section of the right outer wing panel. Previous versions drew fresh air from the front of the Land Rover. The Kodiak MK III heater
produces 17,500 B.T.U/hour. The high speed of the two speed
blower motor moves 190 C.F.M.
A replacment fan motor for the Mk III and Mk IV is NAPA M882
Here are the spec sheet and fitting instructions
for the Kodiak MK III:
Kodiak MK III control panel consist of three controls vertically arranged
on a flat panel. The panel is flat metal, not the standard Land
Rover accessory panel. It is 4 inches by 7 inches and has rounded
corners. The panels are mounted at each corner by sheet metal
screws that have both a slot and hex head. The panel is usually
painted black. The holes for mounting the controls are "D" shaped
to keep the controls from rotating. The look and mounting is completely
different from any other of the Land Rover instrument panels. Since the heater is a dealer installed option and subject to dealer whims and customer preferences there are control panels mounted vertically on either side of the main instrument panel and horizontally to the underside of the panel shelf. There is no one correct location for the control panel.
The layout of the controls from top to bottom are: Temp Control,
Heater and Air Control.
Temp Control - This is a wire pull that controls a valve
located in the path of the coolant intake to the heater core. This
regulates the amount of hot coolant flowing into the heater core
and how hot the core will heat the incoming air.
Heater - This is an electrical switch providing electricity
to the squirrel fan's motor. This switch has two speeds. Extended
to the middle detent the heater works at low speed. Extended completely
the heater works at full speed. The switch has it's own fuse mounted
on the switch body. The two speed function is designed into the
switch and not the motor.
Air Control - This is a wire pull that controls a butterfly
valve in the path of the fresh air intake. It decreases the amount
of air that the fan can blow over the heater core. This control
allows you to close off this passage when the heater is off to
prevent cold of dusty air from being blown into the interior as
Removing the control knobs:
Removing the control knobs can be a frustrating experience if you
do not remember how. The knob is held into place by pressure from
a clip inside the knob pressing against the switch shaft.
There is a hole in the side of the knob near the panel end. You
need to get a fine rod and prise the clip off the switch shaft
while you gently pull the knob off. Just pressing down in the
hole will not work.
I use a fine finishing nail and insert it diagonally against the
base of the clip then lever the top of the nail towards the switch
The two speed switch used in the Kodiak MK III heater is an American
made part and should provide many years of service IF you
keep the switch contacts clean. The switch was manufactured by
the Cole Hersee company of Boston Mass.
The two speed switch used in the Kodiak MK III heater has it's
own 20 AMP BUS fuse mounted on the switch body. There are two wires
going to the switch connected with bullet connectors. One wire
carries 12 volts to the switch. The other goes to the blower motor.
The switch slider has three positions. Retracted is off, partially
extended detents are low speed and fully extended is high speed.
The slider has three contacts. The middle contact is not connected
to anything. The end contacts are connected to each other and makes
electrical connections between both front switch body contacts or
both middle switch body contacts as shown in the switch wiring diagram.
The switch body contacts are mounted into a fiber board. If the
contacts become corroded they will overheat and burn away the
edges of the fiber board holding them in place. This allows the
switch contacts to move away from the slider contacts. When this
happens the heater stops working. I have had success disassembling
the switch and epoxying the contacts back into the fiber board.
This must be done carefully to prevent further damaging the board.
The contacts need to be properly placed for drying.
Prevention is easier than fixing. It is a good idea to periodically
clean the heater switch contacts with a good spray contact cleaner
while moving the switch shaft in and out. If you can keep the contacts
clean the switch should remain in good operating shape.
If your switch is toast, there are a number of plug and play 2
speed heater switches that will do the job. Check companies
that offer restoration parts for 1960's American cars.
A heater works by air flowing through a hot core then into the
car's interior. Anything that lowers the heat of the coolant or
decreases the coolant flow lessens the amount of heat a heater
core can produce. Anything that reduces the airflow cuts back
on the volume of heated air flowing into the car interior. Poor
condition or missing door seals and other outside air leaks counter
the hot air from the heater. Adding insulation and making seals
more effective helps keep the heat in and the cold out.
The blower is mounted on the bulkhead above the hole for the right
hand drive clutch pedal opening. The cover for this clutch pedal
is removed to allow air from the blower to pass into the car's
interior. Some installers cut the hole open to match the fan
ducting while others just used the existing narrow opening. The
clutch pedal opening is much smaller than the fan housing opening
and restricts the amount of air that the fan can push into the
interior. If you are trying to maximize heat you need to
check to see if the bulkhead opening is the correct size or restricting
the fan's air flow. If the hole is the pre-existing
narrow clutch opening you get a large increase in heater flow by
matching the hole in the bulkhead to the fan duct hole
The Kodiak heater will not work efficiently unless the core is
clean both inside and out. Particles can deposit inside the core
and build up to the point where back flushing will not loosen them.
If everything seems to be working and you are not getting enough
heat remove the core and take it to a radiator shop to be boiled
The operating temperature of your engine not only affects it's
operating efficiency, it also affects how much heat your heater
can produce. In cold weather conditions going to the "winter " 180
degree thermostat makes a big difference in the amount of heat a
heater can produce. A radiator muff helps keep the operating temperature
up when the outside air is too cold for the engine to normally reach
operating temperatures. The warmer your engine runs, the more heat
your heater can produce.
The incoming air is cooling the heater core and the coolant is
keeping it hot. The coolant flow must be high enough to keep the
heater core as hot as possible. The heater coolant valve not only
restricts the amount of coolant available to the heater core it
can also get stuck partially open further decreasing the amount
of heat available to the core. A heater coolant valve that does
not get exercised frequently tends to become stuck at whatever setting
it has been sitting at. I have removed my valve completely to maximize
coolant flow into the heater core.
Remember, a warm engine producing a good flow of hot coolant through
a clean heater core is the primary key to maximizing the amount
of heat your heater produces.
The output of your heater is in competition with the outside ambient
air temperature. Bare aluminium is an excellent thermal conductor.
Insulating your car can make a big difference on how warm the
interior of your car will get during cold weather.
The cold air flowing in through seal and body gaps counter the
hot air from your heater. Effective seals can go a long way towards
keeping your Land Rover's interior warm. If your seals are worn
and deformed consider new ones. Do NOT use the factory "genuine"
door and scuttle vent seals made for Series Land Rovers. The company
making them for Rover is making them slightly too large. You will
have a very difficult time closing the scuttle vents and you will
almost never be able to train the leading edge door seals to fold
down properly. Defender scuttle vents work better on the series
LR than the genuine series ones do. The same is true of door seals.
Recommended preventative maintenance:
There are a few things that you can do to keep your heater in good
I suggest disconnecting the heater coolant hoses at the engine
and flushing the heater core with a hose at least once a year. This
will clean out the sediments before they get a chance to compact
and require professional cleaning.
At least once a year clean the contacts of the heater switch. Dirty
corroded contacts create high resistance connections and generate
heat. This heat can destroy the fiber board that holds the switch
contacts in place.
Exercise the temperature and air controls a couple of times a month
to keep them from "freezing" in place.
At least once a year visually inspect the heater and hoses. Clean
and replace as necessary.
If you decide that the hoses going between the engine and heater
core need replacing I strongly recommend that you cut them off the
heater core tubes. These tubes are made of soft brass. Gripping
them with pliers and twisting frequently results in deformed tubes.
Deformed tubes are difficult to seal and can be very difficult to
straighten without removing the core. It has been my experience
that most Kodiak heater core leaks are really leaks around deformed
tubes where the clamps do not seal the hoses.
The interior heater ducting usually has a small door that can be
opened to blow hot air onto the passenger's legs. The hinges can
rust into place. If you use the vent with rusted hinges the metal
around the hinges will bend and fatigue causing the door and hinges
to fall off. It is a good idea to use a light penetrating oil on
the hinges a couple of times a year and exercise the hinges to make
sure that they work properly.
Kodiak MK III pictures:
Kodiak MK III heater core
The core itself is 8 inches by 8 inches by 2-1/2
Overall height top tank to bottom tank is about
9-3/4 inches tall
The inlet tubes are 1/2 inch dia and 4-7/8ths inches
apart centre to centre.
Kodiak MK III heater core housing:
The housing site with the core vertical and the
metal tube facing the hole in the right wing. A flap valve sits
inside the tube to control inlet air flow.
This is the side the fan attaches to. The
inlet openings are parallel to the bulkhead and can be difficult
to get to when removing old stuck on hoses.
Sorry no picture of the fan yet
Kodiak heater MK III air distribution box
The inlet for the heater air distribution box is
the bulkhead hole for the right hand side brake pedal. With
luck the dealer enlarged the hole to the size of the inlet. If
not you can get additional air flow by doing so.
The lever deflects the air to the windscreen when
horizontal and to the driver's legs when down. There are
bumps in the side of the box that allows the lever to be set part
way open. The flap door provides hot air to the passenger's
legs. There is a permanently open vent on the underside that
vents hot air to the passenger's' feet.
Sorry, nothing yet on the Kodiak MK IV heater
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