So, I've been toying with the idea of upgrading the blower motor in my '79 bronco. I have a brand new AC system, and the air is cold, but it just does not blow hard enough on high to cool the whole cabin.

Anyone ever done anything like this? I'm pretty good at fabrication, so I imagine if I could find another motor that spins faster, I could weld it into the stock bracket.

Maybe from a newer bronco??

Some ideas would be appreciated!

Thanks

 

Nobody's ever done this mod?

 

My 78 f150 has the high output heater, and it's like a hurricane of wind. I realize you have a bronco though so?

 

I started a thread about a month ago abt. the same thing. It seems that for the most part people are satisfied with the airflow, I'm not.
I don't have the time to play right now but I'm thinking the same way, adapt a better wheel mtr. combination.
Let us know how you make out.

Dennis

 

Lets figure, we've all been in newer cars where the blower blows REALLY HARD on high. Well that blower just so happens to run on the SAME 12v as our blower motor, so there is nothing special happening there. I just think it's an RPM issue really, i dont think the squirrel cage is spinning fast enough, as I don't think its a vent design issue. On our trucks, the vents and the tubes are HUGE so they are capable of the air capacity, they just dont have a good enough blower. I'm gonna mess around with some different blower motors and see what I find.

 

Good luck, my blower is soooo slow it almost sucks...

 

You said it right there. The blower vent are huge in these old trucks. As they can move volumes of air, just not pressure.

 

What's the difference between a blower motor used in a 1978/79 Bronco and a 1973/79 F100/350?

Nothing. The same ones were used in both, but there are FOUR different types.

D7TZ19805A .. Blower Motor (Motorcraft MM368) / Used with Factory installed Integral A/C, or Hi-Lo Vent (D7TZ19805A replaced D3TZ19805A).

D4TZ19805A .. Blower Motor (Motorcraft MM332) / Use with Dealer installed DELUXE A/C.

D2AZ19805A .. Blower Motor (Motorcraft MM306) / Use with Dealer installed ECONOMY A/C.

E3PZ18527A .. Blower Motor (Motorcraft MM427) / Use with Heater only (E3PZ18527A replaced E2FZ18527A and D1AZ18527A).

 

Thanks for the info numberdummy!! Always enlightening. I was wondering if you are in posession of any engineering documents, like specifications on the motors themselves, IE, RPM speed and such, that would make it easier than trial and error if so.

So I did some discussion with my electrical engineer friend, because i'm trying to figure out why there just isnt enough air coming out of the vents.

I've come to the conclusion that the newer DC motors have more stators in them, making them spin faster on the same voltage. So what I am going to do, is hit the junkyards, and pull a bunch of different blower motors. We will then determine which has the fastest high speed, and fabricate it to fit the original bronco mount. I will take pictures along the way, and i think that will help everyone here. This seems to be a common gripe amongst the bronco/extended/crewcab guys. There is NO WAY the stock fan can really cool those big cabins.

More info as soon as we start the project.

 

I dont know what it is. My dad had a 78 F-250 factory AC, and it would blow as hard as mine on high when his was on med/low. At first i thought well maybe my vents have holes or have come loose. Nope. My blower motor just sucks... and its a new one. I replaced it like 8 months ago because how slow it was and the new one is the same, yet why is my dads so much better? If you go swimming, and its cool out, the defroster cant keep up, and it was a single cab... now its an extended cab so if i dont find a solution by this winter... this may just suck. Ive thought about taking it to an electric shop that rebuilds starters/ alternators and seeing if they can rewind it tighter or something to make it spin faster, but never got around to it. Or i could just swap the motor out of my 65 Wildcat... that thing is like a tornado. But the fan is alot different between the two even though the motors look all but identical.

 

Did you try hooking a hot wire to the motor ? Maby the switch is bad. My blower has plenty of power.

 

It has a new switch too.

 

Hairybox, not meaning to change the subject away from the blower itself, but have you pulled it an checked for obstructions in the vents themselves? I have seen all sorts of stuff in the vents, sometimes due to stuff falling down from the defroster openings. Also the vent doors (vacumn actuated?) could be partially blocked causing the restriction. My kids (never me of course) have lost things down the defroster openings from matches, lighters to fountain pens and have caused airflow problems. Lastly some vehicles (don't know if yours applies) have cabin filters that need to be periodically changed. Hope you find out soon.

 

Link below shows detailed instructions on blower motor replacement. Looks like it's fun!

NORTH COUNTRY SPECIALTIES ® Blower Motor Replacement

Keep us posted as you look for a new motor.

Classic Bronco guys use a Chevy blower motor that seems to improve the performance of the squirel cage blower... Heater Motor Upgrade - ClassicBroncos.com Forums Don't the know the dimensions of the new motor but it might work.

 

Yes, i just had the whole cab/ dash apart. Checked everything for obstructions, leaks, and operation. I also replaced the vent ducting as mine had a few tears in it.

Hmm, reading that bronco post i just thought of something... i wonder by chance if i have the polarity reveresed, or the squirrel cage backwards... im sure i checked this but atm i cant remember for certain.