69 vette vacuum system
 

Hi

I bought last year in Sept. a 69 Vette with a 350 engine. Because the wiper door is not working, I recently started looking into the problem and as I checked the all hoses for right connection, I saw that I have just one vacuum relay for both head lights. All vacuum diagrams I saw till today show two relays, one for each head light. Can somebody tell me if that is normal? I mean it looks normal, since there would be no space for a second one. Even my vacuum tank has just two hose connections, a second head light vacuum relay would require a third hose connection at the vacuum tank.

Thanks for any advice.

Markus

The early 69s had just the one relay, much simpler.


EDIT- correction - all 69s had 1 relay ,in 70 they went to 2 relays

Thanks, that helps me a lot. I have a vacuum plan of 70 Corvette, I assume I can still use this to check the hose connections and the color codings for the wiper system, right?

Markus

Go to the Willcox site for many tech drawings.
Here is a link to all the years of vacuum diagrams , click on "supporting documentation" and roll down to early and late 69s. What is your build date or last 5 numbers of your vin ?
http://willcoxcorvette.com/repairand...lp.php?hID=280

Hi Markus,
In addition to the info Roger passed along I'd suggest that you consider buying the 'Trouble Shooting Guide' that Dr. Rebuild sells. It allows you to understand and TEST each component in the headlight and wiper systems. You do need to have a vacuum pump with gauge (like a Mity-Vac) to do the tests.
It's good to know what's working and what isn't. Many people just begin replacing components and hoses until they finally replace the bad part. This gets expensive quickly and is unnecessary. For example if you cut 1/3" to 1/2" off each end of a hose you have a hose with new sealing surfaces for no cost. Hoses are almost always long enough to do this.
Good Luck!
Regards,
Alan

Thanks Roger and Alan,

The last 5 digits of my VIN are 07927, but when I look at your vacuum diagrams I think I have a early one, because my wiper relay is on RH inner fender and it looks like thats the only difference between early and late 69.
I thought about buying a trouble shouting guide, is the Dr. Rebuild the best or can I also order one e.g. from Ecklers, are they all the same? The same with a vac pump, is one frome a catalog enough?

Markus

Hi M,
According to the NCRS info I'm looking at your 7927 car could very well have the wiper relay on the inner fender, Since it's a Nov. 68 build.
The trouble shooting guide that Dr. R sells is quite a bit diferent than the other guides I ve seen for sale and free on the net. ( Dr. R is a bit DIFFERENT too!)
I'd think any vacuum pump with a gauge will help you out.
Regards,
Alan

Thanks Alan,

I got my trouble shooting guid from Dr. R and a vacuum pump. Today I started searching for failure parts and I found out that both relays are not tight anymore and much worse, it looks like my vacuum tank is leaking as well. I have that big square one with two hose connectors sitting on the LH inner fender and I'm not sure if I have to disassamble the brake cylinder to get the vacuum tank out. Did anybody disassamble a vacuum tank on a early 69 vette and can give me some tips how to do that?

Scholle-

I'm not sure you can rebuild them, I've brazed up cracks in them before but I've never tried to take one apart.

My first question would be how to get the tank off the vehicle. It looks like I have to get the brake cylinder out of the way first.