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Just picked up a 72 numbers matching base 350 Bryar blue In excellent condition except for the notorious headlight lids and wiper door dont work. My question is it possible the same leak or whatever could effect both things or do they run off separate sources ?
Everything runs off the single line coming from the intake behind the carb there.
Make sure to check the stuff before just randomly replacing, make sure to check the on-way valve as they are known to go bad
M
I recently had an issue with my '69 and made up a color-coded diagram to make the problem a little easier. I think the '72 has two Headlight relay valves, but the function is the same.
On some cars the Wiper relay valve is near the master cylinder and on others it is on the passenger side. Hope this helps a little.
I had a problem with my vacuum tank years ago and it is not a fun project to get out of the car and then to repair it. Nobody makes replacements.
I recently had an issue with my '69 and made up a color-coded diagram to make the problem a little easier. I think the '72 has two Headlight relay valves, but the function is the same.
On some cars the Wiper relay valve is near the master cylinder and on others it is on the passenger side. Hope this helps a little.
I had a problem with my vacuum tank years ago and it is not a fun project to get out of the car and then to repair it. Nobody makes replacements.
Got my vac tank out and pending tackle leak detection and fix. Figuring i will use a tub of water and compressor to try to locate leaks. Curious what repair method you went with?? I have read silver soldering is a good method. For sure I want something as permanent as possible cuz I NEVER want to have to take the tank out again!!
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
its rarely ever the vacuum tank...more times than not its the wiper arm relay on those models that have it....then its usually a bad actuator relay....The easiest way to do it is get a vacuum pump, a vacuum gauge and a christmas tree light remote...put the vacuum pump in another room and use a long air hose as the vacuum hose and plug it in as the motor vacuum supply with the gauge in a spot you can see it. turn it on until it reaches about 15 inHg and then shut it off. Using the remote keeps it iin another room so you can listen for leaks and using the remote will keep you from running back and forth and over vacuuming it
Now that you have the tank out clean it up and leak test it just in case it is leaking. You wouldn't want to put it back and then have to take it back out.
Years ago I had vacuum leaks and had to fix several things. The tank was leaking and I repaired it with Silver Solder and then repainted it.
Wasn't sure how long it would last, but this was before the internet and I wasn't able to find another tank. Many years later and it still holds vacuum.
The tank flexes every time you start the engine and it generates vacuum. Eventually the tank will leak.
The area that my tank was leaking was the ribs. I Silver Soldered every one of them even if they were not leaking at that time, just in case.
The yellow lines are where I did the soldering on my tank.
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
the three green circles will be the most likely candidates. They can effect both sides when they leak. the headlight actuator relay will do the same thing as well
Newly acquired 72 with vacuum question
