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Heater/AC blower motor regulator replacement

10K views 7 replies 4 participants last post by  wangchuck 
#1 ·
My weekend adventure involved fixing a heater blower motor that didn't always start up and finding out I didn't have the exact regulator replacement part once everything was all taken apart. To avoid having to do it all over again I made the replacement regulator work with the existing heatsink. It's all back together and working well as of now. I included some pictures of removing the existing newer style regulator from the heat sink, modifying the heat sink and mounting the older style regulator. So far so good and I'll report how this all works out longer term. It did save a lot money not having to purchased full assembly replacement part.
 

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#2 ·
First, this guide should probably be stickied :angel

My fan speeds disappear after having AC or heater on for longer than X minutes. Turning off HVAC and letting it rest for a bit fixes this. I'm pretty certain it's the resistor.

I have a 1999 and wonder if I have to do this process as well? There is the $35 aftermarket part, but do I have the newer style regulator on my 1999MY?

Don't wanna take apart the area and find out I do without being prepared :smile
 
#4 ·
I took just the filter off and can't really see the top, but looks like I have the newer version 129 821 3351

Also it seems the bracket has come loose which is another issue on it's own.

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I am kind of stuck with the workaround you did or pay for the expensive newer part, right?
 
#5 ·
Yes, looks like the newer style that would require the more expensive cover/heatsink/regulator assembly part. If you decide to go the route I did the one thing I would do differently would be to drill and tap for the two mounting screws (M4) instead of using bolts and nuts on the underside. Less work than grinding away the fins on the underside for the nuts. I also had the broken plastic tab that holds the motor clamp. I drilled a hold in the vertical rib below and used a tie wrap to pull down and hold the motor clamp. There's a picture of this in the write up I previously attached.
 
#6 ·
Yes, looks like the newer style that would require the more expensive cover/heatsink/regulator assembly part. If you decide to go the route I did the one thing I would do differently would be to drill and tap for the two mounting screws (M4) instead of using bolts and nuts on the underside. Less work than grinding away the fins on the underside for the nuts. I also had the broken plastic tab that holds the motor clamp. I drilled a hold in the vertical rib below and used a tie wrap to pull down and hold the motor clamp. There's a picture of this in the write up I previously attached.
I would not use a tie wrap as they get brittle and let go with time especially the cheap Chinese ones. It is such a PITA to get in there to service this so it might be a good idea to use piece of galvanized wire which would probably last a lifetime in comparison.
 
#8 ·
Excellent video on getting to the blower resistor:


I followed it, and was out of the job in an hour.

In re: repairing the blower case. I drilled thru the upper and lower case at the flange, and used a long machine screw, washers, and a hex nut. It's been good for the last couple of years.

In re: the correct blower resistor. I have a '98 with the integrated resistor to the heat sink. I bought a used earlier model off of ebay with the replaceable resistor. A future replacement looks a lot less expensive.
 
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