darkshark82

Just got a new to me 79 L82 Auto car. The blower switch works and the blower has three separate speeds. But its just not putting out alot of air its cold but not a bunch of it. Is a blower motor the culprit, I already get to swap the heater core this winter.

jim in oregon

B4 you do anything else..pull the glove box interior(^ screws & a lamp bulb-socket) AND look at the bypass solenoid behind on left side..Should have two vac lines and a cable that actuates this part of the hvac system to properly open close vent doors and allow warm or cold air to properly exit when temp control lever is set from heater/defroster, to cold for A/C. the cable can be adjusted by removing the console carpeted panel on pass.side..(3 screws) and tuning the turnbuckle one way or the other to lengthen/shorten it.. With cable properly adjusted, the mech lever should close the bypass valve completely which closes, the in line heater hose vac solenoid and also opens proper doors for A/C and proper blower force thru proper vents....

Check the above with TEMP CONTROL LEVER SET ON COLD and MAX A/C. selected..

This IF THE TEMP CONTROL LEVER IS SELECTING HEATER/ or defroster, the hot water lines to heater box are opened and differing vents open for defroster or heater...check this on blower hi selection..jim

David in NC

I just trouble shot same problem in my 69. Make sure your blower motor has a good ground (both the connection and gauge of wire). If thin wire, piggy back a thicker gauge ground from blower motor to anywhere nearby on chassis. Simple fix, worked for me.

terry82

check the ac box in the engine bay.were the two parts come together they may need to be resealed.put in a inline water valve shut off.The factory one does not always work that well.

dwkerch

Can't figure out how to post new so I'll interject here!

New blower motor in my '77 w/ AC. Motor is good - hooked it direct to battery and it blows strong. New relay. Blower may or may not come on (AC or heat) when I'm driving and have it set on high, or other speed. Will not blow at idle speed. When driving, comes on, goes off, comes on, goes off, etc. Seems to come on mostly when driving and going up through gears (automatic tranny) at higher rpm? Voltage regulator maybe? I have a new alternator.

Checked ground and it is good. With AC on and blower motor set to high speed, with a 12 volt test light across positive and ground terminals, I have voltage.

I'm stumped, and obviously not the best automotive electrician! Does this sound like a bad, albeit a new, relay?

terry82

sounds like a loose wire.check all your connections.

dochorsepower

OH, that kind of blower motor!