72 - Wiper / Headlight Hose Routing Question

[Scott K.]

Now that I've changed the carb and got the PVC and other hoses correct to factory, i've developed a winking headlight and wiper door upon start-up.
I've replaced most of the vacuum hoses with a Doc Rebuild kit. I say most since i've not changed anything that goes through the firewall (yet).
Replacing the hoses was step 1 in trying to track down the issue.
It did not start after replacing the headlight and wiper hoses, it was before.

Short of pressure testing each of the actuators (which is next), I've come across a connection that does not exist in the Doc Rebuild sheet so thought I'd run it by the
team here.

All of my connections jive with what Mr. Doc Rebuild has on his diagram EXCEPT on the RH side (passenger) near where the three hoses go through the grommet
to the Wiper Door actuator with the button (that the wiper arm rest against), I have a connection that's odd.

The Large Yellow Striped Hose that connects to the metal tube (that goes to the LH SIDE) has a piece of Yellow hose, then a small plastic "T" and then the yellow hose connects to the
inside RH fender mounted actuator. The two sides of the "T" are Large Yellow Stripe, the bottom goes a to a black hose that follows the metal tube and then goes left into the firewall.
This firewall entrance is about centered behind the distributor. In that general area.

Now, the Doc rebuild DOES show a T on the LH SIDE and it would appear to be under the dash. The T goes left to headlight switch and right to Tach solenoid.

Based on the diagram, it would seem that the black hose I'm questioning (that's connected to the subjectT) is mixing atmosphere with vac?
Or.. is that line somehow a vacuum line that actuates something else under my dash? I do have AirConditioning..

My car is a May 72' build.

I could T the LH side hose that goes into the firewall and connect this other black hose to it and see what happens... but thought I'd ask here first if anyone has seen this before?

[Randall K.]

Re: 72 - Wiper / Headlight Hose Routing Question

Scott - I just did this same operation last month to my '72 with AC. The black hose on the right side that tees off from the two yellow hoses (Doc P/N 22) is the vacuum feed for the HVAC control system. This tee is not shown on the headlight/wiper door drawing, but this is what it is. If you've bought the hose kit for the HVAC system, then you'll see this black hose from Doc's P/N G (the tee) leading to the vacuum selector.

Test all your actuators, vacuum relays, and switches. I had 4 bad parts in my system and a bunch of hose ends that were stiff and brittle.

The bad news is that this probably has nothing to do with your winking headlight and wiper door... Make sure you take a look at the vacuum check valve as well.

A few more tips... Use spray silicone on the new hoses as you pass them through the firewall grommets and they should pass just fine. If you replace grommets, use silicone there too.

Feel free to PM me if you have more questions.

Randy

[Scott K.]

Re: 72 - Wiper / Headlight Hose Routing Question

Scott - I just did this same operation last month to my '72 with AC. The black hose on the right side that tees off from the two yellow hoses (Doc P/N 22) is the vacuum feed for the HVAC control system. This tee is not shown on the headlight/wiper door drawing, but this is what it is. If you've bought the hose kit for the HVAC system, then you'll see this black hose from Doc's P/N G (the tee) leading to the vacuum selector.

Test all your actuators, vacuum relays, and switches. I had 4 bad parts in my system and a bunch of hose ends that were stiff and brittle.

The bad news is that this probably has nothing to do with your winking headlight and wiper door... Make sure you take a look at the vacuum check valve as well.

A few more tips... Use spray silicone on the new hoses as you pass them through the firewall grommets and they should pass just fine. If you replace grommets, use silicone there too.

Feel free to PM me if you have more questions.

Randy

Randy,


Thank you for detailed reply. I was hoping to read everything you just posted. Whew... At least Bubba hasnt reworked my 72. I'm now going to systematically ferret out the leak(s). I will likely pm you with a few questions. What color is your 72?

[Patrick H.]

Re: 72 - Wiper / Headlight Hose Routing Question

Make sure the silver check valve is working. If it is not you can often get a winking headlight.

[Alan S.]

Re: 72 - Wiper / Headlight Hose Routing Question

Hi Scott,
The very small black hose and T you mention is an interesting case.
I BELIEVE it's the only hose connection in the vacuum systems that has a CLAMP on it... albeit a VERY small one. I'm thinking it's because the small black hose is more like a 'vinyl', thinner walled, tube and quite different than the rest of the thick walled, rubber hoses in the system.
You'll really be in luck if the clamp is still there!!!
Regards,
Alan

[Scott K.]

Re: 72 - Wiper / Headlight Hose Routing Question

Alan,

Thanks. I have that exact "T" and the clamp. I had thought it was odd to see a clamp and T there.. which is what started the whole thread

[Alan S.]

Re: 72 - Wiper / Headlight Hose Routing Question

Hi Scott,
You're in luck!
Besides the clamp, the T with the nipples in that configuration is a bit difficult to find, too. The small, (1/8"?), nipple is pretty easy to break off, so some owners are looking for them.
Regards,
Alan

[Don L.]

Re: 72 - Wiper / Headlight Hose Routing Question

Here here Alan. Looks like you and I may have similar luck from time to time.

I was successful in gluing mine back together, however, I was successful too in finding an original/used "T". The used one is what can be seen in the car today. The other one appears to have repaired well - keeping it for the next time I break it