Headlights stay up
Thread Starter
Pro
Joined: Oct 2010
Posts: 606
Likes: 48
From: Mystic Ct.
Headlights stay up
Just installed my rebuilt engine and after hooking everything up and firing it up, the headlights came up and now won't go down.
Any ideas or links to help me figure this out?
Thanks
Russ
Any ideas or links to help me figure this out?
Thanks
Russ
Burning Brakes
Joined: Mar 2013
Posts: 1,018
Likes: 581
From: West Monroe Louisiana
2023 C3 of the Year Finalist - Unmodified
Check and make sure that the over-ride under the dash is not down.
I had a similar experience and it was one of the vacuum lines to the
small top inlet on headlight regulators (my 73 has two) was loose and made no vacuum
to keep the headlights down.
Donnie
I had a similar experience and it was one of the vacuum lines to the
small top inlet on headlight regulators (my 73 has two) was loose and made no vacuum
to keep the headlights down.
Donnie
Safety Car
Joined: Sep 2013
Posts: 4,355
Likes: 2,633
From: Draper Utah
^^^THIS^^^
Your leak is probably on the command (small hose) side of the system. Get a vacuum gauge and start working backwards through the system.
Here is the trouble shooting guide:
http://www.corvette-101.com/vacuum.htm
Your leak is probably on the command (small hose) side of the system. Get a vacuum gauge and start working backwards through the system.
Here is the trouble shooting guide:
http://www.corvette-101.com/vacuum.htm
Former Vendor
Joined: Aug 2006
Posts: 76,656
Likes: 1,851
From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
Pull the hose off of #2 and see if you have vacuum.. also check the input hose A at the T for vaccum.
Check both relays and make sure the noses are attached and that you didn't inadvertently knock a hose off. Oh.. and make sure someone didn't pull the over-ride down on you too.
It sure sounds like this might be your issue since the system is designed to open when vacuum is missing from the small hose side. Post back I'll check later tonight or tomorrow.
Willcox
Check both relays and make sure the noses are attached and that you didn't inadvertently knock a hose off. Oh.. and make sure someone didn't pull the over-ride down on you too.
It sure sounds like this might be your issue since the system is designed to open when vacuum is missing from the small hose side. Post back I'll check later tonight or tomorrow.
Willcox
Last edited by Willcox Corvette; Aug 1, 2015 at 08:05 PM.
Melting Slicks
Joined: Apr 2009
Posts: 2,632
Likes: 112
From: Great Plains Iowa
I have a feeling during the engine installation the small hose got pulled off the zinc check valve at the rear of your intake manifold. The little zinc check valve that has an inlet nipple and two outlet nipples. That small hose is what makes the relay valves operate and when vacuum is missing the relay valves "default' to the headlight open position.
Thread Starter
Pro
Joined: Oct 2010
Posts: 606
Likes: 48
From: Mystic Ct.
Ernie,
Found out my over-ride switch is broken. Once I get a new one, I'll start testing more if that doesn't take care of it. Thanks for the GREAT diagram!
Toobroke, I did test the check valve with my MityVac and it tested correctly.
Thanks everyone for their time to answer my question and offer any help I may need.
Russ
Found out my over-ride switch is broken. Once I get a new one, I'll start testing more if that doesn't take care of it. Thanks for the GREAT diagram!
Toobroke, I did test the check valve with my MityVac and it tested correctly.
Thanks everyone for their time to answer my question and offer any help I may need.
Russ
