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I found the vacuum leak!!!



Finally got some time to devote to finding and fixing my nightmare vacuum failure that snuck up on me this fall.

I went to the store and got 25' of vacuum hoses in 3 sizes, then started bypassing and rerouting everything in every combination I could think of, hoping the headlamp doors would suddenly close. No results. I used a rubber hose to listen for a hiss at every T and junction.Nada...
I was really scratching my head, and just happened to be feeling
around the relay thats mounted between the headlamps. All the way on the bottom of that relay shaft is the "total leak" . its so bad that it didnt even hiss coming out. I see now that its what happens when the relays diaphram totally fails( the air just pours out the bottom of the shaft).

Got the relay ordered from Zips today. And earlier, Roy Truelsen had pointed out that I had the wrong hoses so I got the complete color coded hose kit, and the reserve check valve that didnt work either.
I "should"have my headlamps working correctly again around the first of the year..halleluyja..
Then I can move on to the next thing..my fix list seems to get bigger instead of smaller??:L
Ill post the results when I get it done..
Thanks for the help and motivation
I see now that its what happens when the relays diaphram totally fails( the air just pours out the bottom of the shaft).

Correction...actually air would be pouring into the system via the failed diaphram ..:w
The good thing for me is, I "may" get the problem solved without dropping my steering column and pulling dash like you had to do for the tach fix and subsequent vacuum problem. I was just getting ready to do that when I found the bad relay :)
Vacuum problem solved ....

Eureka... sorry tc I couldn't resist :L :L

1 item off of Santa's List ;) Merry Christmas :grinsanta

That's my problem exactly. I had the thing apart once and it was no fun so I dread doing it again. The space is tight, the lights bad and my vision is not what it once was. And I know its back there. One of the other members emailed me some advice. I checked the splitter/filter near the distributor and find vacuum going to the line that runs through the firewall but nothing at the light switch. The vacuum diagram shows a T behind the dash, with one line going to the light switch and the other to the wiper doors (which I found strange because I don't have wiper doors on the 77). So I either pulled a vacuum line off the T or crimped the hose somehow.

The days will get longer and I'll be able to work on the vette and spend some time with the 7 year old, who just doesn't understand why dad wants to fix the car instead of play with him, though he has asked if he'll be driving it when he gets his license.

I told my wife she has my permission to boot my butt out the door tomorrow by noon if its over 60. She has been praying for good weather. I think its the boot thing that she's hoping for.
Everyone enjoy their holidays.

Im sure youve got enough vacuum info to fix your prob. so I wont go there. Instead, Ill use the time to wish you and yours a happy holidays:xmas
You also Rare81 (har on the pun:grinsanta)and everyone also

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