Heater blower motor strangeness

[k20]

Hey all, noticed something odd w/ my blower today. This is all on heat/hot by the way. With the fan on low there is very little airflow(duh), on the next click up, there is a good bit of air, the next click up (second from highest) there is just a bit more than was on low, and then high, is really high, and moves a ton of air. I replaced the blower motor in march or so with one out of a parts truck i had at the time (a suburban with rear air), because mine had started makings a screeching sound. Whats up w/ this problem? Is it a relay somewhere, or is it the blower motor?

O yeh, another thing, the AC box on the outside of the firewall, where the metal tube goes into the box from the dryer(silver canister thing), there is a TON of air (cool feeling though) coming out around the metal rod. Is there supposed to be a gasket around the metal line, or is this an exhaust vent? The faster I turn the fan up, the more air comes out around this hole. Thanks, Chris.

 

[75-K5]

That's how mine is too: nothing, low, a little more, and TORNADO

 

[tx_sub]

i lost the highest fan setting and it was the relay on the ac box. one wire was fried. check your's out. i believe my ac box has some rubber foam stuff around the tube where it comes out of the box.

 

[k20]

no, i mean, when its on the 2nd click from top, one click under hi, there is hardly any air, one click below it has more air moving than that one .

 

[diesel4me]

There is a resistor in the heater box for the speeds--on my non ac trucks its under the hood,and the heater motor wire plugs into it--it has 2 sheet metal screws holding it in.I think on AC equipped trucks it might be under the dash,you can gain access thru the glove box opening.The resistor looks like 3 springs mounted on a small bakelite board,they reduce the voltage to slow the motor speed down.I had to search every truck in the boneyard before I found a good one--they must croak quite often around here,since we need the blower on most of the year around here due to rain and fog,even in the warm months.I jumped the plug with a cotter pin so I could get full speed on my trucks blower motor till I got another resistor. /forums/images/graemlins/crazy.gif

 

[ramses]

Plug the Ac hole up or air will blow out of it. As for the blower motor, a new relay might be needed. It should be below the ac cannister held on with 2 scews.