1980 headlight actuator problem
Thread Starter
Burning Brakes
Joined: Jan 2012
Posts: 943
Likes: 73
1980 headlight actuator problem
The dust boot on the passenger side actuator was missing so I pulled it out to replace it (new shaft boot seal also) . Before putting it back in I decided to put the minivac on it and it would not hold pressure. Ok, new actuator ordered from trusted vendor and just for the heck of it I put the minivac on it and it would not hold pressure either. I rechecked the vac, it holds pressure just fine, the connections were all taped just in case, no good, the actuator moves just fine but will not hold pressure. The vendor is exchanging it, but are these Chinese made, will I ever get one to hold pressure?
Melting Slicks
Joined: May 2015
Posts: 2,365
Likes: 428
From: Cape Girardeau Missouri
Yes, they are Chinese made. You'll probably get one that holds vacuum eventually but how long it lasts is anyone's guess. This problem has been going on for years and I'm surprised it has not been addressed.
Thread Starter
Burning Brakes
Joined: Jan 2012
Posts: 943
Likes: 73
Time to start looking at electric, without the nightmare of pulling out the headlight switch on this 80 and a $900 price tag?
Melting Slicks
Joined: May 2015
Posts: 2,365
Likes: 428
From: Cape Girardeau Missouri
It's a problem with ALL vacuum products. Check them FIRST before installing! Slightly leaking switches that can easily be disassembled (like on the headlamp switch, the HVAC selector, override switches, warm-water shutdown switch, etc.) are often indefinitely (read years if not decades) repaired using nothing but some silicon grease (aka "plumbers' heat-proof grease").
Before you give up on vacuum do a little searching for a forum member who repairs original actuators.
Before you give up on vacuum do a little searching for a forum member who repairs original actuators.
Melting Slicks
Joined: Feb 2017
Posts: 3,232
Likes: 1,232
From: PHX AZ
plump it up!
Dear Black C-3....I am messing around with one of the lights on the 69. 51 year old headlight actuators. I always do a leak-down test.
According to the AIM -20" of vacuum is what they recommend. 20" up and 20" down. I listened to the opposite tube to immediately tell if there was an o-ring problem...there was none.
The 51 year old actuators held vacuum for 8 hours! The leak-down was 10" over 8 hours. Or said another way...after 8 hours they still had 10" in them.
(The problem with mine is the adjustment of 'landing'....one corner is too low...)
One way to 'swell' rubber o-rings is to soak them in liquid silicone....this causes the rubber to 'plump-up' and be more compliant.
Temperature is also a factor.... I have to assume you weren't messing around in the driveway at 0° F!
Unkahal
According to the AIM -20" of vacuum is what they recommend. 20" up and 20" down. I listened to the opposite tube to immediately tell if there was an o-ring problem...there was none.
The 51 year old actuators held vacuum for 8 hours! The leak-down was 10" over 8 hours. Or said another way...after 8 hours they still had 10" in them.
(The problem with mine is the adjustment of 'landing'....one corner is too low...)
One way to 'swell' rubber o-rings is to soak them in liquid silicone....this causes the rubber to 'plump-up' and be more compliant.
Temperature is also a factor.... I have to assume you weren't messing around in the driveway at 0° F!
Unkahal
Last edited by L-46man; Feb 24, 2020 at 12:39 PM.
