2 questions about accessory controls

[shady]

My 88 burb has the intermitant wiper system. It will only work on high speed. Is there a normal relay the controls slowspeed and delay? if so where is it at?
And what controls the vent selection for the heat/ac. I can change between hot and cold fine, but it always comes out the dash vents facing me. I would at least like to direct it at the windshield for defrost/defog.
I'll keep digging in the chilton but thought I'd ask the brotherhood too. Maybe its common problems? Thanks

 

[folkenheath]

I dont know about the intermittent wiper control, I thought it was all in the switch. But the flappers for the vents under the dash in an AC truck are controlled by vacuum that comes from the engine, along with several vacuum diaphrams under the dash, directed by a mechanical vacuum manifold/switch connected to the control lever. Maybe your vacuum line going under the dash was melted in the fire? The stock lines are usually small plastic hard lines, somewhat flexible, but brittle when old. They are not usually rubber, but they aren't fire proof either.

 

[shady]

I hooked one up that was a rubber line and appears to go through the dash. I may have over looked something too though. It doesnt appear to have a vac. leak with the way it runs, but I geuss its deffinatly possible. I'm gonna go poke around in a few minutes.

 

[folkenheath]

I hooked one up that was a rubber line and appears to go through the dash. I may have over looked something too though. It doesnt appear to have a vac. leak with the way it runs, but I geuss its deffinatly possible. I'm gonna go poke around in a few minutes.

It's also common for the seals around the flapper doors to dry out, and let air go by in all directions regardless of flapper position. I imagine excess heat might make that worse. But I would be checking vacuum first. Maybe even use a hand vacuum pump in the interior just to test the system out under the dash if you don't find anything obvious.

 

[shady]

I found a rubber bushing thing going through my firewall. It appeared to have a little nub in the middle so I got a hold of it with pliers and it was a small hard tube melted off (you were right) I got it hooked up and it works better but not perfect. Oh well I at least can direct some air up on the windshield now.

 

[folkenheath]

Good find! Good luck with the wiper delay.