Heater Upgrade Fan Part Number

starfire340 · 11-21-2009, 01:33 PM

I know this has been beat to death, but its getting near winter so the GM heater upgrade might be getting some attention again. Just wanted to let anyone interested that the Siemens part number for the short shaft blower motor is the 102 NOT the 105. I just went thru this with my parts guy at the local parts store and verified that the shaft lengths are different. The 105 shaft is the long shaft version. Going to finish up the upgrade this afternoon.
Just wanted to pass this along.
mark

ctm · 11-21-2009, 01:42 PM

also I have seen the parts packed in the wrong box so you think you are getting the correct one but you are not. Correct shaft length is 1 3/16" , the longer one is 1 13/16". Check before you leave the store.

CJ Chet · 11-22-2009, 09:55 AM

I just went to Autozone and told them I need a blower motor for an '86 CJ7, and guess what they show as the replacement?
Siemens PM102.

**Mike Romain** · 11-22-2009, 10:14 AM

Something wrong here gents... The GM Blazer blower motor is Way bigger than a CJ7 blower to the point you have to do bodywork to make it fit. You have to cut the hole bigger.

I can't see how they could call that motor a CJ7 one because it just plain won't fit.

poppatello · 11-22-2009, 10:21 AM

Quote:

Originally Posted by Mike Romain

Something wrong here gents... The GM Blazer blower motor is Way bigger than a CJ7 blower to the point you have to do bodywork to make it fit. You have to cut the hole bigger.

I can't see how they could call that motor a CJ7 one because it just plain won't fit.

Yes, they do have two parts with the same number. I found out the hard way. Another note though, I have a guy who works on jeeps and sometimes knows what I'm looking for before I tell him. So if I walk into the parts store and tell him I'm looking for a heater blower, I don't even have to ask him half the time. I went to NAPA for the first heater and they gave me the smaller one for the Cj. The fan will not fit as it hits the heater backing plate. You have to get the blower with the longer shaft. You should take your old heater blower with you and line the blower plates up side by side. If the shaft is the same length, it's the wrong one. Something they fail to mention when doing the swap...

poppatello · 11-22-2009, 10:22 AM

Quote:

Originally Posted by CJ Chet

I just went to Autozone and told them I need a blower motor for an '86 CJ7, and guess what they show as the replacement?
Siemens PM102.

That blower does look like the smaller Cj blower. It is not the correct one. When you put the blowers side my side, the upgrade blower will be double the size of the older one...

**Mike Romain** · 11-22-2009, 10:42 AM

Quote:

Originally Posted by poppatello

Yes, they do have two parts with the same number. I found out the hard way. If the shaft is the same length, it's the wrong one.

Umm backward there I think. The shaft has to 'be' the same length, the long one won't work, the fan hits.

The proper one is 1 3/16" , the longer one is 1 13/16".

**keith460** · 11-22-2009, 11:07 AM

I always thought and bought the fan motor for the Chevy Blazer "without" A/C and it is the correct one. Chevy Blazer motor for A/C applications will have a longer shaft that you do not want. Got it from NAPA.

texasimport · 11-22-2009, 11:07 AM

And yes you get to cut the hole in the fire wall to make that bigger motor fit. Just finished mine this fall here in Colorado and with a soft top we can now not wear coats anymore. Coldest morning this year was around 17. Not tooo bad, warms up in about 10 minutes. My teenager uses this as his daily driver and trust me I would hear it if him and his little brother weren't toatsy for the 35 mi round trip to school and back.

Now I get to swap the motor blower switch from the PO toggle back to a 3 way.

**Mike Romain** · 11-22-2009, 11:29 AM

Quote:

Originally Posted by keith460

I always thought and bought the fan motor for the Chevy Blazer "without" A/C and it is the correct one. Chevy Blazer motor for A/C applications will have a longer shaft that you do not want. Got it from NAPA.

I have done two of them and am about to do a third in January. I asked for one for a 73 Blazer 350 with AC and both fit. I am up in Canada though...

I used this write up: Jeep Heater Blower Motor Upgrade

CJ Chet · 11-22-2009, 11:30 AM

Quote:

Originally Posted by keith460

I always thought and bought the fan motor for the Chevy Blazer "without" A/C and it is the correct one. Chevy Blazer motor for A/C applications will have a longer shaft that you do not want. Got it from NAPA.

The long shaft motor in your photo is the Siemens PM105. The PM102 is the proper one. Although Autozone calls out the PM102 as a replacement, you DO still have to trim the hole. When I asked for the Blazer motor I got the long shaft model.

**keith460** · 11-22-2009, 11:54 AM

Quote:

Originally Posted by CJ Chet

The long shaft motor in your photo is the Siemens PM105. The PM102 is the proper one. Although Autozone calls out the PM102 as a replacement, you DO still have to trim the hole. When I asked for the Blazer motor I got the long shaft model.

It's not a long shaft but maybe looks that way in the photo because a nut is screwed on to the end. The shaft is the same length as the OEM fan motor, 1-3/16" length.

Napa p/n 655-1039

**scottymac62** · 11-22-2009, 02:04 PM

The Blazer motors at O'Reilly Auto Parts are the VDO brand blower motors and the correct shaft length for our Jeeps is part # VDO102. I installed one in my heater box when I upgraded my heater unit in my 77 CJ-5. Works great!

kauffballs · 11-22-2009, 02:30 PM

Ok so I am a new Jeep guy. please tell me about the upgraded heater.....i have a stock 84 CJ7 will this help my heater that works put out more heat? i assume that is what the point is but not sure.
Thanks

**Mike Romain** · 11-22-2009, 02:41 PM

Quote:

Originally Posted by kauffballs

Ok so I am a new Jeep guy. please tell me about the upgraded heater.....i have a stock 84 CJ7 will this help my heater that works put out more heat? i assume that is what the point is but not sure.
Thanks

Yes, that is the point. Heat! The people that designed the Jeep heater must have lived in Florida or they had a really sick sense of humor...

The GM blower motor puts out more on low that the Jeep one puts out on high. With it in, I can defrost 'all' my windows at -25C no problems. My wife and I and our two cats even did a 1200 mile run last winter at -25 to -35C and we didn't need gloves or hats and we had our coats open even.

Apparently there are two motor shaft sizes down in the US for the 73 Blazer 350 with AC. I have always gotten the right one up here in Canada, the one with the shorter shaft of 1 3/16" long.