My Blazer Heater Blower Motor Upgrade
ThisGuyUKnow
Full Time Jeeper
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- Location
- Harleysville, PA
- Vehicle(s)
- 1986 CJ7 Laredo 4.0,Nv3550,D300 Twin Stick,AMC20 3.31, 31 BFG
Honda vtx1800c
So while I wait on my spacer bolts for the 4.0 head I decided to do the blazer heat blower motor upgrade. I had to pull my dash to more easily install my YJ pedals and I am moving from the Gulf Coast, where an extremely cold winter is like 20 deg F, to Macomb,Il where the winters can get to well below 0.
There are tons of write ups available so I wont be saying anything that isn't already available online.
First off I told the autozone monkey I needed the blower from a 1973 Chevy Blazer with a 350 and A/C and I got a siemens motor that seems to match what everyone else is using. Mine had an extra piece of metal around the back of the motor which added about a quarter of an inch to the width of it. I started to cut this piece off but got bored quickly and gave up (My sister's dog has eaten every pair of safety glasses despit my best effort to keep them from him and the sparks kept hitting me in my eyes) So I got a hole saw big enough to fit the back of the motor with the metal surround.
The saw I needed was 3 5/8'' amd ran me 20 bucks at Lowe's plus I had to buy the damn pilot bit which was another 18 bucks (I will be trying to return these tomorrow) In retrospect I regret going the hole saw route over just cutting a hex shape with a dremel. This is because the wood I used to catch the pilot bit just tore up and the hole saw broke loose, chewed up my fire wall, cut my hand, and was generally a PITA. I ended up with an egg shaped hole that was like a pig's butt hair too far over to the right (looking at the fire wall from inside the cab) Luckily I was able to get enough thread on all the studs to thread the bolts on and pull the heater box into place.
Other than that problem, the mount holes on the blower lined up with the original, the shaft fit the original fan with no fuss, and the positive lead that the harness plugs into lined up in the exact same spot. I may have to run a dedicated ground but I won't know until I get the truck wired back up. I did bench test it witht he fan attached and definitely felt like I opened a can of hurricane so I think this may be the ticket....
Overpriced Hole Saw
Original motor sticking through firewall
Dusty Heater box
Old motor Exposed
Old motor attached to fan
Larger, Egg shaped hole drilled. Notice the carnage to the surrounding area.
Handy dandy touch up paint.
New motor on the heatet box. I also took the opportunity orange glowthe box and the surrounding areas.
Shot of the new shaft on the blades.
new motor in the fire wall.
I will try to rig up the old harness and test out the different settings to compare the air flow tomorrow. Overall this took me about 45 minutes of actual labor. If you still ahve your dash in I would figure around 1 hour and if you you have the on board air to work around I'd say plan for another 30 minutes, unless it leaks and doesn't work like mine and you don't mind just cutting the hoses like I did.
There are tons of write ups available so I wont be saying anything that isn't already available online.
First off I told the autozone monkey I needed the blower from a 1973 Chevy Blazer with a 350 and A/C and I got a siemens motor that seems to match what everyone else is using. Mine had an extra piece of metal around the back of the motor which added about a quarter of an inch to the width of it. I started to cut this piece off but got bored quickly and gave up (My sister's dog has eaten every pair of safety glasses despit my best effort to keep them from him and the sparks kept hitting me in my eyes) So I got a hole saw big enough to fit the back of the motor with the metal surround.
The saw I needed was 3 5/8'' amd ran me 20 bucks at Lowe's plus I had to buy the damn pilot bit which was another 18 bucks (I will be trying to return these tomorrow) In retrospect I regret going the hole saw route over just cutting a hex shape with a dremel. This is because the wood I used to catch the pilot bit just tore up and the hole saw broke loose, chewed up my fire wall, cut my hand, and was generally a PITA. I ended up with an egg shaped hole that was like a pig's butt hair too far over to the right (looking at the fire wall from inside the cab) Luckily I was able to get enough thread on all the studs to thread the bolts on and pull the heater box into place.
Other than that problem, the mount holes on the blower lined up with the original, the shaft fit the original fan with no fuss, and the positive lead that the harness plugs into lined up in the exact same spot. I may have to run a dedicated ground but I won't know until I get the truck wired back up. I did bench test it witht he fan attached and definitely felt like I opened a can of hurricane so I think this may be the ticket....
Overpriced Hole Saw
Original motor sticking through firewall
Dusty Heater box
Old motor Exposed
Old motor attached to fan
Larger, Egg shaped hole drilled. Notice the carnage to the surrounding area.
Handy dandy touch up paint.
New motor on the heatet box. I also took the opportunity orange glowthe box and the surrounding areas.
Shot of the new shaft on the blades.
new motor in the fire wall.
I will try to rig up the old harness and test out the different settings to compare the air flow tomorrow. Overall this took me about 45 minutes of actual labor. If you still ahve your dash in I would figure around 1 hour and if you you have the on board air to work around I'd say plan for another 30 minutes, unless it leaks and doesn't work like mine and you don't mind just cutting the hoses like I did.
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