Headlights hope someone can help
Thread Starter
Instructor
Joined: Jan 2009
Posts: 193
Likes: 0
From: NJ
Headlights hope someone can help
My headlights no longer work because my cam doesn't produce enough vacuum. I have several options to fix the problem but I am on a budget and was hoping someone out there has some advice.
I found a electric vac pump on summit for $280 that I may end up going with simply bc it may be the cheapest option.
I also thought about getting rid of the entire vacuum system for the lights and converting to electric. But the kit was $1000. I was thinking about maybe trying to make my own electric kit and was wondering if anyone out there has done so? and if so how much did you do it for?
Any help would be great thanks!
I found a electric vac pump on summit for $280 that I may end up going with simply bc it may be the cheapest option.
I also thought about getting rid of the entire vacuum system for the lights and converting to electric. But the kit was $1000. I was thinking about maybe trying to make my own electric kit and was wondering if anyone out there has done so? and if so how much did you do it for?
Any help would be great thanks!
Race Director
Joined: Dec 1999
Posts: 19,610
Likes: 778
From: Forked River NJ
How much vacuum is your motor producing. I ran a pretty big cam in my motor. 252/260 @ .050 duration and I was able to pull 8 inches and my headlights worked fine. You may have problems elsewhere in the vacuum system. What cam are you running?
Le Mans Master
Joined: Aug 2001
Posts: 7,804
Likes: 4
From: Standing still with all my might Texas
Cruise-In X Veteran
St. Jude Donor '09-'11
Liz's 68 only produces 8" of vacuum at idle. It's not enough for the brake booster to work properly, but the headlights and wiper door still work fine despite the fact that there are some small leaks in the system.
I suspect you may have much bigger vacuum leaks in your headlight system which are causing the problems.
Thread Starter
Instructor
Joined: Jan 2009
Posts: 193
Likes: 0
From: NJ
I am running the trex cam its 242/248 .612/.615 lift. I never measured my vacuum but when I had a much smaller cam the lights worked fine. that is why I suspected it to be the cam. I guess I can try to check for a leak in the system again but last time I didnt find anything.
Pro
Joined: Jul 2010
Posts: 691
Likes: 25
From: Boynton Beach Florida
I have 5-7" of vacuum in mine and the lights work great after I replaced the relay's. I did the actuators but would have to rev the engine a bit at idle to get them opened but the relays got them up at almost the same time at idle. I would pull a hand vac test on them and see what happens.
Instructor
Joined: Dec 2010
Posts: 169
Likes: 1
From: Merritt Island Florida
I did the 'Killer Lights' electric conversion, using Firebird actuators, C4 headlight controller and headlight switch. I got rebuilt actuators and everything used from e-bay, mayge $300 worth. It works great, I am completely happy with it.
Carl
Carl
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
Do you still have a functional vacuum tank and do you have a 'check valve' installed in the vacuum line going to that tank? If not, there is no way for you to maintain an adequate level of vacuum...even if you engine was capable of doing so.
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Thread Starter
Instructor
Joined: Jan 2009
Posts: 193
Likes: 0
From: NJ
Thanks for your response I knew there had to be a way to do it on a budget. If I cant fix my vac problem I will def be giving this a try next.
Thread Starter
Instructor
Joined: Jan 2009
Posts: 193
Likes: 0
From: NJ
I have 5-7" of vacuum in mine and the lights work great after I replaced the relay's. I did the actuators but would have to rev the engine a bit at idle to get them opened but the relays got them up at almost the same time at idle. I would pull a hand vac test on them and see what happens.
I check the vac in my manifold at idle and its 9 inches...I could not find any leaks in my vac lines so I am thinking it may be the rubber seals and boots in the actuator. I saw a replacement kit in ecklers for 34.99 so I am going to give that a chance you think that will fix my problem? Or should I buy new relays also?
Le Mans Master
Joined: Aug 2006
Posts: 7,426
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From: mount holly NC
2025 c3 ('74-'82) of the Year Finalist - Unmodified
2019 C3 of Year Finalist (appearance mods)
There is a STICKY up top, it will tell you how to test the relays and the actuators.
Many times the witches hat in the actuator goes bad first.
Test first and then order what you need and you'll keep the cost down.
Many times the witches hat in the actuator goes bad first.
Test first and then order what you need and you'll keep the cost down.
Thread Starter
Instructor
Joined: Jan 2009
Posts: 193
Likes: 0
From: NJ
Drifting
Joined: Jul 2009
Posts: 1,534
Likes: 14
From: Dallas-Fort Worth TX
Liz's 68 only produces 8" of vacuum at idle. It's not enough for the brake booster to work properly, but the headlights and wiper door still work fine despite the fact that there are some small leaks in the system.
I suspect you may have much bigger vacuum leaks in your headlight system which are causing the problems.
Thanks,
Le Mans Master
Joined: Aug 2001
Posts: 7,804
Likes: 4
From: Standing still with all my might Texas
Cruise-In X Veteran
St. Jude Donor '09-'11
Hey Ya'll, what is the bare minimum vacuum figure that will operate the brake booster and provide adequate safe brakes? I see that 8" is not enough. I need to go check again. But at idle in park, I am about 11-12 " from what I remember. I have not tried to lock the brakes up yet since my new engine build. Just curious. I want to ensure I am in the safe zone. My headlights work fine. Pop up just as fast as they did with the original engine.
Thanks,
Thanks,
I ended up installing a electric vacuum pump for the booster.
(and it worked great after I re-mounted the booster in the proper location, linked it to the correct hole on the brake pedal, and replaced the cheap non-correct foreign booster with the proper one for the car)
I probably should try temporarily hooking the booster back up to manifold vacuum just to see if it would have been enough to make the system work properly without the electric pump.
Drifting
Joined: Jul 2009
Posts: 1,534
Likes: 14
From: Dallas-Fort Worth TX
I just went through troubleshooting a whole slew of brake issues on the 68 (Bubba worked overtime on this car). In the process I read a lot of old threads and articles on vacuum boosters. The most common numbers I saw for minimum vacuum for a brake booster to work correctly was 15 or 16".
I ended up installing a electric vacuum pump for the booster.
(and it worked great after I re-mounted the booster in the proper location, linked it to the correct hole on the brake pedal, and replaced the cheap non-correct foreign booster with the proper one for the car)
I probably should try temporarily hooking the booster back up to manifold vacuum just to see if it would have been enough to make the system work properly without the electric pump.
I ended up installing a electric vacuum pump for the booster.
(and it worked great after I re-mounted the booster in the proper location, linked it to the correct hole on the brake pedal, and replaced the cheap non-correct foreign booster with the proper one for the car)
I probably should try temporarily hooking the booster back up to manifold vacuum just to see if it would have been enough to make the system work properly without the electric pump.
15-16" ... uh oh... Well I know I am not there. It drops even lower when I put it into gear. I could install a electric vac pump in the place of my old gas/charcoal canister. Are they really that expensive as mentioned above?
Last edited by Rebelrob; Mar 4, 2011 at 11:53 PM.
Le Mans Master
Joined: Aug 2001
Posts: 7,804
Likes: 4
From: Standing still with all my might Texas
Cruise-In X Veteran
St. Jude Donor '09-'11
I mounted it on the driver's side wheel well just below the horn relay, but if you can make room for it where the charcoal canister is that would probably be a better option (vacuum tank takes up too much of that space in the 68).
Cruising
Joined: Feb 2011
Posts: 10
Likes: 0
From: DORSET OHIO
vacuum problem,three minute fix,on your vacuum tank in front of car,take the supply line off,check vacuum ,if you have vacuum,then take a small drillbit the same size of hole on vacuum tank and clean out hole,theyr noted sometimes for pluggin up over time,,,,,,,,,,check vac.lines,headlight sw.to overide also
