Hello reader, Here is my guide to how I installed a Mark VIII fan in my 1994 K1500. I was new to the process, so if you are too, this may help.
The materials I used include 8 gauge wire
A volvo dual speed fan relay
A 3 position switch
A few colors of 16 gauge wire
A Mark VIII fan out of a Lincoln Navigator
Some aluminum bar stock for brackets
A battery stud extender
A 40 amp self resetting circuit breaker
Misc. wire dressing, connections, and hardware
There is the finished install on the engine bay.
Step Zero- disconnect the positive battery cable.
First I took off the fan shroud. It is a bunch of 12mm screws that hold it on. The ones on the bottom are easier to get at by taking off the plastic skid plate behind the bumper. I realized that after the fact.
Next I unbolted the clutch fan, there are four nuts that hold the water pump pulley on, I believe they are 13 mm. They are a bit awkward to get at because when you try to turn them the fan spins. I used two more 13mm wrenches placed on the next two nuts to keep the fan from spinning while I removed each one. I got some grade 8 lock washers and put the nuts back on to secure the water pump pulley.
There is all the old stuff out of the way.
First I made a bracket to hold the Volvo Relay. This relay I got on Ebay for about $10. Salvage yards or parts stores also work, although new ones are typically $40+.
Bracket is two L shapes that grab the grooves on the back.
I put a battery bolt extender on my positive terminal, it is a parts/hardware store item. I paid like $3 for it at Fleet Farm (shout out to the mid-westerners)
I ran an 8 gauge wire with a heavy duty lug from the battery to the big lonely plug on the Volvo Relay. About half way I put in a 40 amp auto-reset circuit breaker. Again, parts store. $5.
Next I ran the wires for the relay into the cab. The middle plug with the yellow and yellow/white stripe wires is the light duty circuit. To activate your fan, you have to ground out one of those wires. For a dual speed, it is both. I have my wires to a switch, the switch has ON-OFF-ON, so it grounds to a solid ground in the cab and each ON is a speed.
I used a piece of an aluminum Tecumseh lawnmower engine block as my switch panel, screwed to the dash above the fuse box.
The connector with the two thick wires is the heavy circuits. That is the main supply for both fan speeds. On the relay it has each wire labeled, 1 or 2. They correspond, so little wire 1 switches big wire 1. I ran more 8 gauge wire from those to the pigtail for the fan. The blue and inside black wires are HI and LOW speed. The plug for the connector is labeled + and -, so you will see which wire is ground. I grounded the wire to the core support.
Now that the wiring is done, conduit, heat shrink, electrical tape. Whatever tickles your fancy.
Next is the fan. I used some aluminum bar stock to make brackets. Forgive picture quality. I have an L bracket that bolts to a hole in the core support on the Pass. side and a hole in the fan shroud. I have a straight bar that bolts to one of the stock lower fan shroud bolt holes in the core support and a bracket on the fan. On the top I drilled a few holes and bolted a bar to the top with a curve to accommodate the arc in the top of the fan. This bolted to bars that used the existing bolt holes in the core support from the original fan shroud.
The final step was some unrelated stickers to add horsepower. Now, I'm good to go.
Thanks for reading.
The materials I used include 8 gauge wire
A volvo dual speed fan relay
A 3 position switch
A few colors of 16 gauge wire
A Mark VIII fan out of a Lincoln Navigator
Some aluminum bar stock for brackets
A battery stud extender
A 40 amp self resetting circuit breaker
Misc. wire dressing, connections, and hardware
You must be registered for see images attach
There is the finished install on the engine bay.
Step Zero- disconnect the positive battery cable.
First I took off the fan shroud. It is a bunch of 12mm screws that hold it on. The ones on the bottom are easier to get at by taking off the plastic skid plate behind the bumper. I realized that after the fact.
Next I unbolted the clutch fan, there are four nuts that hold the water pump pulley on, I believe they are 13 mm. They are a bit awkward to get at because when you try to turn them the fan spins. I used two more 13mm wrenches placed on the next two nuts to keep the fan from spinning while I removed each one. I got some grade 8 lock washers and put the nuts back on to secure the water pump pulley.
There is all the old stuff out of the way.
First I made a bracket to hold the Volvo Relay. This relay I got on Ebay for about $10. Salvage yards or parts stores also work, although new ones are typically $40+.
You must be registered for see images attach
Bracket is two L shapes that grab the grooves on the back.
I put a battery bolt extender on my positive terminal, it is a parts/hardware store item. I paid like $3 for it at Fleet Farm (shout out to the mid-westerners)
I ran an 8 gauge wire with a heavy duty lug from the battery to the big lonely plug on the Volvo Relay. About half way I put in a 40 amp auto-reset circuit breaker. Again, parts store. $5.
Next I ran the wires for the relay into the cab. The middle plug with the yellow and yellow/white stripe wires is the light duty circuit. To activate your fan, you have to ground out one of those wires. For a dual speed, it is both. I have my wires to a switch, the switch has ON-OFF-ON, so it grounds to a solid ground in the cab and each ON is a speed.
I used a piece of an aluminum Tecumseh lawnmower engine block as my switch panel, screwed to the dash above the fuse box.
You must be registered for see images attach
The connector with the two thick wires is the heavy circuits. That is the main supply for both fan speeds. On the relay it has each wire labeled, 1 or 2. They correspond, so little wire 1 switches big wire 1. I ran more 8 gauge wire from those to the pigtail for the fan. The blue and inside black wires are HI and LOW speed. The plug for the connector is labeled + and -, so you will see which wire is ground. I grounded the wire to the core support.
Now that the wiring is done, conduit, heat shrink, electrical tape. Whatever tickles your fancy.
Next is the fan. I used some aluminum bar stock to make brackets. Forgive picture quality. I have an L bracket that bolts to a hole in the core support on the Pass. side and a hole in the fan shroud. I have a straight bar that bolts to one of the stock lower fan shroud bolt holes in the core support and a bracket on the fan. On the top I drilled a few holes and bolted a bar to the top with a curve to accommodate the arc in the top of the fan. This bolted to bars that used the existing bolt holes in the core support from the original fan shroud.
You must be registered for see images attach
The final step was some unrelated stickers to add horsepower. Now, I'm good to go.
Thanks for reading.
