ive had a problem, more of a story, dealing with my vent door selector switch. we all take for granted the ease of just selecting 'vent' in our third gens and air coming out the vents, or selecting 'heater' and air coming out of the floor.
well my problem is that when i select 'vent' air comes out of every single spot, but there's a very very annoying constant hissing from the vacuum leak coming from the vent door selector switch. ive gotten a replacement switch (AC Delco) but that to no avail, does not work either.
my father and i tore one of the old ones up (i think it was the AC Delco one) and found that all it is comprised of is one side for vacuum inlet/outlet, and another rotating side with a diaphragm looking rubber seal to send the air where its supposed to go.
well our logic says that the seals there are dried up in both the original and replacement switches which is causing the air to just rush out and cause no vacuum pressure at all anywhere. while exploring the switch, we accidentally broke a tab off of the clip that holds it together, which we fixed with putting a small bolt/nut on it. i realized that when its tight, it wont leak even though it did prior.
also on this seal there seemed to be some grease looking substance possibly to help seal it off better.

now to the problem (after the story, i warned you it would be a story), recently this switch has began leaking again, i believe its due to the nut loosening on the back of the switch. i am going to tighten it but a thought arose which is why dont i add some grease to the rubber seals, it appeared to have some on there before. but then another idea came to mind, which was: how about adding vasoline to the seal. because its petroleum based, this would cause the rubber to expand more than usual, which would in turn help seal it. but i also know that the down side is the rubber wearing out quicker. would this be a good idea or stick with the safer option of just re-tightening the nut?
im really hoping to be able to be done with this problem so if anyone has any other suggestions or input i'd really really really appreciate it!

thank you and sorry for the extremely long post!

-brian

Maybe something in the following link will be helpful:

https://www.thirdgen.org/forums/inte...ctor-disc.html

JamesC

thank you, that did help a lot...gonna try the brake fluid trick. does brake fluid degrade the rubber like oil does do you know? i dont want to ruin it, i just want it to work

Just a stray thought - might try restaurant grade lubricant/sealant - used it every week on the slushie machine at work - it's guaranteed to not adversely affect rubber while keeping it supple and lubricated.

And, it's edible!!

oil based will swell the rubber and work great untill the rubber falls apart

I'd try silicone.

JamesC

yeah, im still on the fence about using an oil based product just cuz i dont want to ruin the rubber quite yet lol. i'm going to try to see if the seal has become detached and then tighten up the nut i have on there (cuz the plastic clip fell apart on it, so we replaced it with a tiny bolt/nut) and then go from there first before swelling the rubber. hopefully it works, first i have to pass inspection though, damn bastards failed me for one tire being more worn than the others cuz a local alignment shop screwed me when i first bought my tires...bastards!

Not sure if they still offer it, but Firestone used to offer a lifetime alignment for like $150 - it stays with the car and can be done at any Firestone shop nationwide - they will align and realign as often as needed for whatever reason - I got this for my car.

{but go figure, it was 2 years ago and I haven't had any alignment issues since }

i had it re-aligned by a different shop. seems to be good, but i was told that the way that the tire wore, it would just keep wearing if i left it there. i didnt believe them so i guess im the sucker lol. i ordered up a new tire so hopefully that'll work.

also i pulled out the selector switch for like the 1,000th time (yay! signal balloons and confetti and streamers falling from the ceiling) and tightened up the nut/bolt that we put in place of the plastic clip and i secured it with a tight wrapping of teflon tape (i didnt have loctite on hand and teflon tape usually works well for me as a threadlocker stand-in) and it hasnt leaked all night so we'll see if that works lol