Headlights work but slow?
Thread Starter
Pro
Joined: Jun 2007
Posts: 688
Likes: 1
From: Stevens Point WI
Headlights work but slow?
The headlights on my 69 come up only when you rev the motor up, and the same to bring them back down.
I have a 540 BB with a larger cam but all my vacuum lines are new and the acuators have new seals in them, also the vac can is new too.
Also the headlights are the only vacuum item I am running as I installed the long style hood on my car.
Would the valve in the front inbetween the headlights be getting week and cause this problem?
I have a 540 BB with a larger cam but all my vacuum lines are new and the acuators have new seals in them, also the vac can is new too.
Also the headlights are the only vacuum item I am running as I installed the long style hood on my car.
Would the valve in the front inbetween the headlights be getting week and cause this problem?
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Yes the relays are the most common problem for the vacuum headlights. Generally though you have better vacuum at low RPMs, so it's puzzling why it works when you rev. Maybe you have both low vacuum and a bad check valve. That might explain why they operate when the engine is revved. Lack of vacuum with a bad check valve will usually raise and lower the headlights when the engine is first started.
Race Director
Joined: Nov 2002
Posts: 12,142
Likes: 54
From: Taylor Michigan
Not uncommon with a lot of HP. Wild camshaft will cause that problem. If you can live with the condition, leave it alone. The wiper door may also be affected. But not on yours if the door is not used any more....
Thread Starter
Pro
Joined: Jun 2007
Posts: 688
Likes: 1
From: Stevens Point WI
Thanks for the replies
I have a all new kit from ZIP with new check valve and filter along with all new lines.
The only part not new would be the single relay inbetween the headlights.
I guess I can live with it for now and see if it improves with use.
I have a all new kit from ZIP with new check valve and filter along with all new lines.
The only part not new would be the single relay inbetween the headlights.
I guess I can live with it for now and see if it improves with use.
