Heater blower need help
 

My 72 c10 with a/c only has low speed on the blower. Just replaced the blower motor, same results. What should i do next. Never worked on a/c equiped truck before. All help is appreciated a bunch............
Thanks
bob

Re: Heater blower need help
 

BCOWANWHEELS
Check the ground wire from the relay inside the cab on the firewall.
It is very short
It is located up high between the glove box and passenger side wall.

There is a short ground wire that is supposed to go one of the shroud bolts that come through the firewall
Easy test is to attach a short piece of wire while it is on high from the relay to ground.

A lot of folks do not get the ground re-attached correctly while working on the heater coil.

The symptoms are
Low= Low
Medium= Medium
High = Very SLow

Re: Heater blower need help
 

I havent got nothing but low speed. Even with oem blower motor

Re: Heater blower need help
 

I'm not sure but do our trucks some a blower motor resistor? we know thats a very common problem on later models when one or more of the variable speeds go out.

isn't there something like a resistor that by the fan switch?

edit:
just looked it up.
this is what you need. it's mounted to the back of the fan control area i believe
https://www.classicparts.com/1960-72...iABEgLjq_D_BwE

Re: Heater blower need help
 

I bet thats it, could somebody tell me exactly where its located. I,am crippled and movement is real tough for me.
Bob

Re: Heater blower need help
 

Maybe the resistor, but I'd suspect a bad switch first. Hi doesn't go thru the resistor, but low does. The switch is easy to get to and test. No sense spending money without a quick continuity test of the switch.

Re: Heater blower need help
 

Resistor is 10.00 at oreillys, i,ll check switch also. Thanks.

Re: Heater blower need help
 

Here are some good info pages.
Most times on a AC truck it's the switch. It's a easy fix. I have fixed many of them by taking them a part and cleaning the contacts and regreasing them. A lot of times it's the plastic connector gets hot and melts and the terminals want make contact also. :chevy:

http://67-72chevytrucks.com/gallery/...A_C_wiring.JPG

This shows you where everything is.

http://i1233.photobucket.com/albums/...Untitled-3.jpg

http://67-72chevytrucks.com/vboard/a...1&d=1163599872

http://67-72chevytrucks.com/vboard/a...1&d=1163599872

Re: Heater blower need help
 

perfect............ you blessed me tremendously.......... thanks bunches

Re: Heater blower need help
 

Your welcome.:metal: