H1 Blower Motor Problems

HVAC Article

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Blower Motor Assuming that the control circuit is working properly i.e. you have voltage at the motor. There has been a lot of problems with these motors burning out. Water gets into the bearings, they start making noise and they're gone. Some owners have been able to lubricate the bearings every few months and get more life from the motors.

One cheap solution for those who are constantly changing blower motors; NAPA part # 455-1744 is a perfect match for the blower motor in a Hummer with the HVAC upgrade - you just have to swap the squirrel cage from your original motor by removing and reinstalling one nut. See the paragraph below for other issues. Autozone part number is 129669. Cost for the NAPA part was less than $35 (vs. ~$100 for the AM General part)

Note, the fan pictured is the latest AMG part. It comes with the rubber vent/ drain going to the motor (pictured under the wires). The motor is sealed except for this vent. This vent probably cools the motor when it's running. Delco P/N 52466052 Type # 15-8532 SKEW # (bar code) 3666655395 .

For our Canadian owners the NAPA number there is Everco M1874

If you have replaced the blower and you still don't have air at the vents make sure your new blower motor is rotating in the right direction. There are two identical "universal" motors which are used in trucks (not just Hummers) and they spin in different directions. Too see if this is the problem switch the positive and negative wires on the blower motor. You may also have to put the squirrel cage (fan) from the factory blower on the new motor.

(7/29/2006) This Delco P/N Delco P/N 52466052 Type# 15-8532 Bar Code SKEW# 3666655395 is a direct replacement for the oem unit. The oem motors and most of the NAPA and aftermarket stuff is the cheap made in china or Mexico junk. They generally last months to a year or so. I went through 3 aftermarkets in about 2 years, then I used this delco P/N and it has been healthy for 3 years or so. Any parts outlet that sells delco or a GM dealer can get it. Of course there is a chance that Delco it buying and boxing the same junk now. I got this P/N from an employee of the vendor that supplies the AC units to AMG. He admitted a high failure rate with the Mexi crap and good survival rate of the Delco unit. The bad news is that it will cost $50-60 for the Delco as opposed to `$20 for the cheapie.


My blower only runs at one speed.

Resistor packFirst check your fuses. One fuse controls all the lower speeds and is located in the main fuse box (7D on a 98). The high speed fuse is an inline fuse located under the hood on the passenger side to the right of the variable speed blower motor resistors and between the snorkel and the alternator.

If this doesn't cure the problem Your resistor pack is probably the culprit. Either the wires are loose or the resistors are defective. The pack is located on the passenger side firewall behind the coolent overflow tank. Pull the connector off and clean the contacts with some fine sand paper. Then grease the contacts with dielectric grease. This will keep the moisture from corroding the contacts. A bad blower relay which is located just above the fan unit under the crash pad on the passenger side will keep the fan from running. If this doesn't solve the problem it's either the wiring, or the HVAC control head.

Rebuild the Blower Motor:

I found a permanent fix for this. After you get the motor out, drill out the rivets that hold the motor together. Carefully pull the assembly apart, you might need to pry it with two screwdrivers on opposite sides. The magnets and the brushes make this job really tricky. Inside the dimple on the end of the motor housing is a bronze spherical bushing. The bronze bushing gets rust on it from the steel housing and then the shaft squeales. The inside diameter needs to be drilled out to fit a standard radial ball bearing purchased from Bearings Inc. or other bearing company Careful, you only drill the bronze bushing part way through (the width of the bearing) so that it retains the bearing. Push the bearing into the bushing and then slip this onto the motor shaft. Use dental floss to tie the brushes out of the way. Carefully slide the motor shaft assembly into the housing. The magnets will pull the shaft against the sides. I vaguely remember wrapping the motor shaft with something to help it stay centered as I pushed it in. Push the shaft all the way in until the spherical bushing into the spherical dimple retainer. Slip the dental floss out to allow the brushes to drop back onto the armature. Bolt the two motor housing parts together with small 4-40 screws and nuts. Reinstall the motor assembly. Enjoy the quiet. Now the motor shaft spins in the ball bearing and the spherical bearing allows for slight misalignment. This is better than the original design.