defrost problems 72 blazer

[Team]

woke up this morning with snow and realized my defrost vents are not blowing air, all the hoses seem to be in place, any suggestions? My heater also sounds like a cricket, anyone know how these things get lubricated?
I have to say you guys are all a great help, its nice to be a part of something that works well.

[HI OFCR]

Are you gettting air flow out of your lower vents? If not your blower motor may have crapped out. They are easy to replace and cheap. Only like 20 bucks at the local parts store.

[Team]

yea, getting plenty out of the lower vents, maybe the flap isn't closing all the way, cable is a bit stiff.
Also just discovered as I drove it in the rain for the first time that it leaks where the vent window and top come together, the seals are new there too, does anybody know a trick to putting them in so they wont leak?

[k5hart]

If there is air coming out at the floor but you have it set to defrost then the flap in the divertor box may be broken. It's a pretty common problem. I just got done fixing mine. To check the cable you should be able to see it moving the lever on the box in between the floor vent and the big box holding the heater core. The only other thing I can thing of is the duct work has come off.

[BBrendal]

If it is equiped with A/C check the vacum hose from the firewall on the pass side right above the autotrans dipstick tube make sure the thin hose is connected to the vacum cannister (see pic) that is on the ac housing and the thicker hose is connected to the back of the intake manifold. the connectios are on the rear of the cannister.

[Team]

both of these are connected although there was a vacuum line to the far left that had come off, doesn't seem to make any difference. i did just notice air only comes from the center vents, nothing below either. i guess i'll take it apart tomorrow.
thanks for the suggestions.

[k5hart]

There should be 2 far left vacuum hoses. One for the fresh air door in the cowl and one for the heater shut off valve. None of the vacuum should really effect the defrost vents I believe. It's probably the divertor box. Here is a link to my thread where I fixed the flap.

http://67-72chevytrucks.com/vboard/s...d.php?t=432168

[old man jimmy]

my guess would be the deverter flap also. I posted about it a long time ago, but looks like a good time to repeat. After breaking a couple on mine I found that when the controls are set to "vent" the flap was hanging horizontal, and when off road all it took was a good jolt for the flap to break from it's own weight. Then I started putting the control in a different position when off the road. End of problem. I don't remember where I set the control to, but probable don't matter as long as it hangs vertical.