Hi All,

I have done everything I could with my 2 Vacuum switches. I say 2 because my first wasn't working correctly and leaking. The second is doing a similar thing.
I packed them both with grease but I still hear a leak at the switch on both.
I want to know if either of the 2 sides of the switch can warp? If so how do I tell? T from Willcox told me to pack them with grease as they are only 2 pieces of plastic with holes held with a plastic pop rivet in the center.
I am using the 1977 Chevrolet service manual and the Willcox diagrams.
All vents and air valves work separately but not correctly. I tested all of them with a Mighty Vac on each.
I even took off all of the vacuum lines, then attached the black main vacuum line and put it to the other 3 open lines, when I did that every duct opened from the car's vacuum
The best I got when I returned the 4 lines to the cap on the Vacuum switch, was everything working except MAX on the A/C and a hiss in the off position. I hear an air leak at the control.
I tried both switches and there is a hiss with both.
I would love to get the system working correctly.

Thanks
Jack
1977 L-82

 

Replace the plastic rivot with a pop rivot or a screw and nut. Tighten until there is good resistance to movement.

 

One thought. Won't a screw & Nut eventually loosen up?

Thanks
Jack

 

Are you sure it isn't leaking vacuum between the switch and the rubber double-elbow that slides onto the two plastic "thingies" (nipples?) the elbow slides onto? That was where mine was leaking. I put silicone grease on the nipples and it solved my problem. I used silicone grease because since it is made for weather stripping, it should not harm the rubber double-elbow.


Pete

 

I've used the nylon screw and nut before and then melted the end of the screw when I got it adjusted.

 

Do these not have rubber in them anymore ?

 

solid plastic on both sides (that I could see).

Jack

 

NO WAY ! That's BS Ruined a perfectly good design.
Here's a couple originals,guess I should have saved more.

 

Hi Roger,

Sorry!
I guess that the one I thought was original I am still not sure of.
The one (that came with the car) was 1 plastic side and one rubber that I was able to remove with the same design as yours in the pix. The one that I got in Aug 2011 is the same. It leaked when I tried it but I just tried the grease fill, that I didn't do when I got it.
I just took one good center pop rivet, I then took both springs and put them on the latest one after I coated the insides with lithium grease. The 2 sides are tight as can be.I don't want to take it apart to see if the latest one has a rubber side unless it doesn't work.
On top of all my other crap, my eyes are loosing their ability to focus and I need lens transplants, so I can't really distinguish certain things, like black on black. I wiped off the grease and used a screwdriver at the edge and the rubber popped out with the 4 legs on the back. Is it possible that the manufacturer put it in wrong so I am not getting the correct vacuum to the correct line?
I will be testing it within the hour or so as I just got a new center console top.
My original was all beat up with every mount hole broken off. I took out and put back everything on the new top and I will post what happened.
For some reason, the ashtray cover does not fit right. I have to try to somehow align it better and not break the under mount ears before the whole cover goes back on.
I am lining the tranny tunnel now with a Dynamat type substance to keep the heat out first.
If it doesn't work as Willcox's diagram, I am going to try and connect the main vacuum line to it and move the top lever to one notch at a time, then put my vacuum gauge to see which of the 4 lines have suction and connect it as I go.

Thanks
Jack

 

I hope that fixes yours. If I had more than the 2 I saved I would send you one. About the only thing that goes wrong with the old ones with the rubber is the center rivet.
Irritates me that these aftermarket manufactures have to cheapen up the original design on things to make a buck.
Good Luck

 

Roger,

Thank you very much for your kind offer!
As I said, there is no rubber inside the 2 I have.
If it won't work this time I will gladly pay you for it as I really do not want to pull the dash apart anymore.
This is the 4th or 5th time.
Let me ask, I have been using duct tape on the ends of all the venting behind the dash to stop any leaks, it can't be seen when the dash is all together.
cool or uncool move?

Thanks
Jack

 

I will add one thing.
When I go to a parts house and the moving, electrical or mechanical part says "Made in China" I refuse it. (bulb sockets or such I deal with) Most of the parts crap out.
My litttle guy's lunch box I bought a tester for and it was positive for lead.
I wish that we still had things made in the USA with American pride that we could buy, especially for us collectors, who spend our hard earned dollars and we don't want to buy the parts over or do the job 5 times, because they crap out on us.
I hang in my friend's shop at times and he gets cars back and he has to eat the labor over again from parts crapping out on him.
The parts houses are bitching too.

Jack

 

OK,

After trying all different types of combinations of the 4 vacuum lines, I still cannot get the hissing to stop in the off position or the control to work correctly.
I tried with or without the 5 hole cover with the capped end.
I will have to buy another vacuum switch.

Thanks
Jack

 

Hi All,

I found last night an OEM vacuum switch online. It had the same numbers (48053) that Peter's original switch had so I took it for stock. It was sold with old original box too, with numbers I looked up and found it to be OEM Delco Switch.
If I have to repack it I will as the grease probably has dried up.

Thanks
Jack

 

My post above, #4, doesn't make any sense at all given what I now see as the vacuum switch the OP and other respondents are talking about. I thought the OP meant the vacuum override switches under the dash, beside the steering column. Sorry for the goofy post


Pete

 

Hi All,

Thanks for all of your help.
I received the NOS switch today and all is well.
I have to stop buying crap control parts.

Thanks
Jack
77 L-82