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Blower upgrade popping fuses

BobbyA

Full Member
Joined
Feb 8, 2007
Messages
248
I did the swap and had to put a spacer between the motor and the heater box to keep the cage hitting the back side. Problem is I keep popping fuses. Have the motor grounded to the dash and it is getting power from the original wiring. Is there anything I should be looking at? I also blocked off the fresh air hose from the outside and ditched the box. Anybody ever try to put a pusher fan on the outside to push more air in?
 

DirtDonk

Contributor
Bronco Guru
Joined
Nov 3, 2003
Messages
47,355
Never heard of anyone doing it just that way. Usually a vent-scoop is attached to the hood to direct more air into the grille when moving.
The usual direction is to aim the opening towards the windshield (counter-intuitively) to take advantage of the high-pressure pile of air there being dammed up by the windshield at speed. But either direction can help.

Is that the box you ditched though? So now there is nothing between the hood and kick panel, and your heater box/plenum is just open to the interior of vehicle?
If so, is that where you're thinking of putting a fan?
Doubt a fan is going to be as effective as mother nature. Especially one small enough to fit over the heater box opening. But hard to say for sure until it gets tried.
Then again, isn't that what the heater fan is doing anyway? And now that you have a more powerful one, the need for auxiliary fan or ducting is lower in theory.

For blowing the fuses, what rating are they? Still the stock 20a I think it is?
A very few people have had this issue after the upgrades, but nothing consistent that we can track the why's-and-wherefor's on. You may just need to uprate it to the next step of a 25a fuse. Should still be well within tolerances as long as everything else is good.

And speaking of which, I would start measuring voltages at different places. Starting at the battery to get a baseline and then at the heater switch to make sure it's not losing some in-between.
Then I'd run a separate ground from the dash to the body. If you're going to be using the dash itself as a ground, might as well make sure the dash is grounded too. Relying on the almost 50 year old bolt connections may not be as good as it once was.

How is your body ground? Did you add some?
Should be a good one between the battery and the fender nearby (like Ford did originally) and an additional one between the engine and the firewall (like Ford should have done!) to make sure everything can get the voltage and current flow it needs.
Maybe the heater motor is just struggling with lower voltage than it wants to see.

Good luck.

Paul
 

bchesley

Full Member
Joined
Dec 21, 2012
Messages
327
How healthy is your charging system and battery connections? Electric motors do weird stuff when they don't get the required power.
 

VB67bronco

Jr. Member
Joined
Nov 1, 2018
Messages
93
Loc.
Va Beach
I did the swap and had to put a spacer between the motor and the heater box to keep the cage hitting the back side. Problem is I keep popping fuses. Have the motor grounded to the dash and it is getting power from the original wiring. Is there anything I should be looking at? I also blocked off the fresh air hose from the outside and ditched the box. Anybody ever try to put a pusher fan on the outside to push more air in?

I grounded my blower motor to the Metal screws on the heater box itself. Also make sure the Brown wire giving the Heater/fan switch is on a 20 Amp fuse all by itself.
 

75MIKE

Sr. Member
Joined
Aug 22, 2001
Messages
955
Loc.
NE Washington
Good luck trying to defrost your windows with no outside air coming in through your heater core. Unless you have AC on all the time to help dry the air.
 

pcf_mark

Bronco Guru
Joined
Jun 11, 2010
Messages
3,574
I had my blower fuse GLOW because the resistance was super high in the fusebox. The fuse did not blow and I will never understand why. I took the fuse out and it was rusty along with the clips in the fusebox. I cleaned the clips and put in a new fuse no more glow.

The new fan and cage move a ton of air it would need to be pretty cold for me to need more.
 

BRONCO26

Sr. Member
Joined
Jan 17, 2006
Messages
508
Loc.
SENOIA
Check your blower resistor on the deck of the housing make sure it’s not touching anything metal to ground it out to blow fuse
 

blubuckaroo

Grease Monkey
Joined
Jun 11, 2007
Messages
11,795
Loc.
Ridgefield WA
^ Yes check that you haven't shorted the heater resistors.
The blower speed is reduced with resistors mounted inside the duct.
 

Pa PITT

Contributor
Bronco Guru
Joined
Jul 15, 2005
Messages
11,252
Loc.
Stephenville TEXAS
.. After I did my Blower Motor update.
I had issues with the cage hitting the frame work. It made noise & It was slower than normal. Slower than the up grade not slower than the stock Ford blower. I've sure had my share of issues with this upgrade.
Almost hard to call it an Upgrade.. But it is much better If you can stand the noise. It's worse than owning a Diesel.
... So after I got it centered & I got it equipped with a 20 amp fuse ..& Nothing bumping Mine is ok now.
 

JB Fab

Sponsor/Vendor
Bronco Guru
Joined
Mar 21, 2004
Messages
1,240
I would confirm that you don't have a 24V motor.
 

73azbronco

Contributor
Bronco Guru
Joined
Nov 11, 2007
Messages
7,796
Pulling this up, wonder if you all are using the motor I'm using vs what they are selling now as a heat blaster upgrade?

I cut my box per directions but came to realize the motor mounting flange is not as pictured on the heat blaster picture on WH or other websites.

This is what I got and it DOES NOT fit.

https://www.amazon.com/plastic-Heater-ECCPP-1987-1996-1988-1997/dp/B01LZXMZOO

My motor is from a Ranger or f150-250 ford part f2tz-18527-a , the heat blaster is closer to a mustang blower motor, dont know that part number.

It fits, but not. With only about 1/16th of clearance between hitting the front of case or back of case, and only about 1/8th of clearance top to bottom side to side, I just cant seem to get to a sweet spot that it wont hit while running. Worse with gasket in place.

Hopefully did not cut to much of box to put in the right motor and cage, hopefully they just miss boxed a later model bronco motor into my order. Going to Randys Monday to find out.


This is what you need to fit right:

https://www.wildhorses4x4.com/images/uploads/11819_4790_popup.jpg
If its rubbing it aint right.
 

DirtDonk

Contributor
Bronco Guru
Joined
Nov 3, 2003
Messages
47,355
Can you post a pic of your squirrel cage too? There have been batches even of the correct motor, where the fan/cage supplied was not the correct one and the offset made it virtually impossible to fit. But that did not effect the motor mounting itself, so you still have to deal with that unfortunately.

I don't know for a fact we still use it, but the traditional upgrade was not a Ford motor at all, but a GM motor that was larger, more powerful and had a larger fan. In recent years there have been others that have used a later model Ford motor and fan, but I don't remember what that was out of.
I'm sure there are old threads here though, that would indicate what Ford model was compatible.

If it was from a truck though, it must've been an '80 through '86 then, because your motor fits just about everything else! I don't remember it being a motor from the '70's, but I would not want to trust my memory on that score.

Sorry to hear you're having this trouble. It's hard enough cutting through the old box with the parts that do fit!
Good luck.

Paul
 

OX1

Bronco Guru
Joined
Aug 26, 2003
Messages
3,458
Pulling this up, wonder if you all are using the motor I'm using vs what they are selling now as a heat blaster upgrade?

I cut my box per directions but came to realize the motor mounting flange is not as pictured on the heat blaster picture on WH or other websites.

This is what I got and it DOES NOT fit.

https://www.amazon.com/plastic-Heater-ECCPP-1987-1996-1988-1997/dp/B01LZXMZOO

My motor is from a Ranger or f150-250 ford part f2tz-18527-a , the heat blaster is closer to a mustang blower motor, dont know that part number.

This is the motor/fan I used also (I'll walk 20 miles out of my way not to use chevy parts :p).
Definitely needed to be spaced out a decent amount,
but fits fine without hitting anything inside. I used small plastic spacers I got
at Lowes I think. Had to cut edge of metal a bit too, on the bottom edge, to meet airbox contour.

20171230_090804.jpg

20180102_135557.jpg

20180102_135916.jpg

20180102_140735.jpg

20180102_140826.jpg

20180102_152437.jpg
 

sykanr0ng

Bronco Guru
Joined
Aug 11, 2014
Messages
5,363
'87-'97 F series and '87-'96 Bronco.
Since a range like that only confuses the counter monkeys at cheapo auto parts tell them '92 F250.
 

DirtDonk

Contributor
Bronco Guru
Joined
Nov 3, 2003
Messages
47,355
Luckily he's already got the motor. Looks like it works with some trimming and spacing though.
That looks like a pretty slick fit after trimming OX. Nice looking indeed.

I'm sure you've said before, but how's it working so far?

Paul
 

OX1

Bronco Guru
Joined
Aug 26, 2003
Messages
3,458
Luckily he's already got the motor. Looks like it works with some trimming and spacing though.
That looks like a pretty slick fit after trimming OX. Nice looking indeed.

I'm sure you've said before, but how's it working so far?

Paul

Thanks. Have it in bronc, and hooked it straight to batt
with 10 guage (going to use relay on high setting), and it
blows very hard.

But rig is still in a million pieces, so don't know about
actual perf yet.
 
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