Headlight actuator beyond repair?
Thread Starter
Drifting
Joined: Jan 2002
Posts: 1,663
Likes: 139
From: Vail AZ
Headlight actuator beyond repair?
The guy who had custody of my ‘73 for the past several years replaced both headlight actuators and valves. The left one doesn’t go up with the headlights on. Referencing several online videos I’ve determined through testing that the valves and right side actuator is good and that the left one is bad. (Duh?). But I don’t think the seal replacement will fix my problem. If I apply vacuum to one side of the actuator it will pull vacuum out the other side. It seems as if the large central diaphragm is the issue. Which sucks being as though these are brand new actuators.
Every “fix” I can find only addresses the seal that goes in around the rod. I can’t find anything referencing a fix for the diaphragm itself. Is it a throwaway?
On a side note, both “closer” fittings on the back sides of the actuators are pointed toward the center of the car. All the pictures I have stumbled across show those fittings pointing outboard. Did he put them on the wrong sides or am I finding incorrect pictures?
Thanks in advance for any help.
Tom.
Every “fix” I can find only addresses the seal that goes in around the rod. I can’t find anything referencing a fix for the diaphragm itself. Is it a throwaway?
On a side note, both “closer” fittings on the back sides of the actuators are pointed toward the center of the car. All the pictures I have stumbled across show those fittings pointing outboard. Did he put them on the wrong sides or am I finding incorrect pictures?
Thanks in advance for any help.
Tom.
Melting Slicks
Joined: Feb 2018
Posts: 2,331
Likes: 725
From: Marietta GA
I would move (temporarily). the broken the broken actuator to the side that is working, do the same with the Relay Valve. If you confirm they are bad, get them from Willcox, as they stand behind what they sell. I have read that often times, the valves and relays are bad right out of the box. What are you using for vacuum source, since your engine is out?
Thread Starter
Drifting
Joined: Jan 2002
Posts: 1,663
Likes: 139
From: Vail AZ
Thanks for the replies. I’ll switch them to their correct sides. I called my buddy and he said he ordered them off of the auction site about 5 years ago. Too bad....
I’m using a hand vacuum pump to test everything. Anyone know for sure about this though? It seems as if vacuum traveling all the way through the can leaves no doubt as to the diaphragm itself being bad and beyond repair. ??? Or maybe I’m just moving it enough to cause that vacuum transfer???
I’m using a hand vacuum pump to test everything. Anyone know for sure about this though? It seems as if vacuum traveling all the way through the can leaves no doubt as to the diaphragm itself being bad and beyond repair. ??? Or maybe I’m just moving it enough to cause that vacuum transfer???
Thread Starter
Drifting
Joined: Jan 2002
Posts: 1,663
Likes: 139
From: Vail AZ
I dodged a bullet. I took both actuators off and swapped them to their correct sides this morning. I opened up the actuator that wasn’t working and discovered that the inner diaphragm was just fine. My air movement was no more than a result of the diaphragm moving air as designed. I just didn’t move it far enough to completely stop it, thus my mistake in thinking that it was open.
My issue turned out to be the flange being bent where the seal rides. This is the inner seal that is replaced with the common rebuild kits. I was able to properly flatten that sealing surface and reassemble the actuator so that it now works just fine.
I must say though that I was disappointed to find that both outer dust boots were torn on these “new” actuators. I’m not sure if I can buy just the dust boots, but I’ll look into that later. For now I’m just happy to have one free fix on this car. Now to go buy a piece of vacuum hose, as one side was not long enough to reach the properly-oriented fitting.
My issue turned out to be the flange being bent where the seal rides. This is the inner seal that is replaced with the common rebuild kits. I was able to properly flatten that sealing surface and reassemble the actuator so that it now works just fine.
I must say though that I was disappointed to find that both outer dust boots were torn on these “new” actuators. I’m not sure if I can buy just the dust boots, but I’ll look into that later. For now I’m just happy to have one free fix on this car. Now to go buy a piece of vacuum hose, as one side was not long enough to reach the properly-oriented fitting.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
If they just have cracks (no actual missing material), you might be able to seal and salvage them with Permatex Ultra-Black RTV sealant. Contrary to all other silicone-based sealants, Ultra-Black is formulated to tolerate and resist degradation from petroleum-based materials (oil, grease, gasoline). When the boot is in a 'relaxed' position, wipe the damaged area down with alcohol or lacquer thinner, then dab some RTV over the damage and let it cure. It will stay flexible after curing and should seal to prevent moisture, etc from getting into that boot and the actuating mechanism.
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Thread Starter
Drifting
Joined: Jan 2002
Posts: 1,663
Likes: 139
From: Vail AZ
Aquarian: I appreciate the offer. It seems that the dust boots are less than $10.00 a piece if one shops a bit so probably not worth the cost of shipping them.
7T1vette: That’s probably worth a try. While they’re not terribly difficult to remove and replace, now that both are back on the car I’ll probably not be doing anything with them for a while.
Funny that I can find the entire rebuild kits for as little as $24.00 for two (maybe even cheaper if I shopped around a bit more) but the pair of dust boots Would cost almost that much by themselves. I think if I do end up buying anything I’ll probably just buy the whole kit so that I’m ready for the next inevitable failure.
Thanks to everyone for your input.
7T1vette: That’s probably worth a try. While they’re not terribly difficult to remove and replace, now that both are back on the car I’ll probably not be doing anything with them for a while.
Funny that I can find the entire rebuild kits for as little as $24.00 for two (maybe even cheaper if I shopped around a bit more) but the pair of dust boots Would cost almost that much by themselves. I think if I do end up buying anything I’ll probably just buy the whole kit so that I’m ready for the next inevitable failure.
Thanks to everyone for your input.
Last edited by any4xx; Aug 21, 2020 at 05:01 PM.