Headlamp Actuator Help Wanted!
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From: Omaha NE
Headlamp Actuator Help Wanted!
I have narrowed my headlamp problem down to the actuators. Does anyone know how to troubleshoot the actuator itself? I need to know if I need to buy a whole actuator(s) or just the seal kits.......Does anyone have any current links or info on disassembling the actuator itself? Thank you.
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Re: Headlamp Actuator Help Wanted! (Trevelisek)
If you have the actuator out of the headlight housing then you can test to see if it functions when vacuum is applied to either of the two ports. If vacuum is applied to the front side port then the acutator rod should move out, if it is applied to the back port it should draw the actuator rod in.
How fast it moves in and out depend on how good the diaphram is. If it is cracked or deterorated then it won't operate at all or maybe very slowly. If you apply vacuum to one side and hold your finger over the other port and feel fairly strong vacuum then the internal diaphram is gone. If the actuator diaphram appears to be working, then slow operation is probably because of a leaking seal, or very stiff mechanical linkage, which can be cured by replacing the shaft seal and lubricating the linkage.
How fast it moves in and out depend on how good the diaphram is. If it is cracked or deterorated then it won't operate at all or maybe very slowly. If you apply vacuum to one side and hold your finger over the other port and feel fairly strong vacuum then the internal diaphram is gone. If the actuator diaphram appears to be working, then slow operation is probably because of a leaking seal, or very stiff mechanical linkage, which can be cured by replacing the shaft seal and lubricating the linkage.
Melting Slicks
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Re: Headlamp Actuator Help Wanted! (Trevelisek)
I had a pin hole rusted in one of my actuators, but if your actuators look good from the outside, then it's probably the seals.
Here's an article on replacing the seals... http://www.corvettemagazine.com/2002...s/lights-1.asp listed (with others) under the Miscellaneous section at http://www.corvettefaq.com
Here's an article on replacing the seals... http://www.corvettemagazine.com/2002...s/lights-1.asp listed (with others) under the Miscellaneous section at http://www.corvettefaq.com
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Re: Headlamp Actuator Help Wanted! (Smokehouse69)
What smokehouse is saying...if I may, is that once the the internal diaphram is gone...you've got to replace the entire actuator. If you can isolate the seal...then a seal rebuild kit will work. I've worked through this with my 78 and concluded my diaphrams are going and I will need to replace the actuator. Now...I've learned of a source that rebuilds your originals...if that's important to your particular project.
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Re: Headlamp Actuator Help Wanted! (Trevelisek)
If they are still in place (or out of the car for that matter), unhook the two hoses. Place a finger over one of the holes, if you can push the rod in or pull it out, then there's a leak. If you keep your finger over the hole, you shouldn't be able to move the rod. If the rod moves, you should be able to hear or feel the leak around the seals etc.
If you try to remove them with your hood on, be careful and cover the hood and front clip edge with a lot of duct tape. I unhooked my hood support so I could open it a little further, very tight squeeze . . . next time I'll take my hood off.
If you try to remove them with your hood on, be careful and cover the hood and front clip edge with a lot of duct tape. I unhooked my hood support so I could open it a little further, very tight squeeze . . . next time I'll take my hood off.
Melting Slicks
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Re: Headlamp Actuator Help Wanted! (74-Roadster)
"be careful and cover the hood and front clip edge with a lot of duct tape."
I'd like to add to that statement that if you do leave the hood on, you can get a little extra room to remove the actuator by moving the back of the hood forward (and conversely the front of the hood moves backward) to the "most open" position. That doesn't read too clearly. Basically, you're opening the hood as much as possible, not letting it lock in place (which lets the nose of the hood move forward about an inch).
I'd like to add to that statement that if you do leave the hood on, you can get a little extra room to remove the actuator by moving the back of the hood forward (and conversely the front of the hood moves backward) to the "most open" position. That doesn't read too clearly. Basically, you're opening the hood as much as possible, not letting it lock in place (which lets the nose of the hood move forward about an inch).
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Re: Headlamp Actuator Help Wanted! (Trevelisek)
Thank you one and all for your input! The response and links have been very helpful! My only real choice now is whether to replace the actuators completely, or just replace the seals.....I am leaning towards just replacing the seals if I can get away with it.....the casings for the actuators seem allright, so I hope the diaphragms are serviceable......That was an excellent article link (Jan.2001), by the way....
:cheers:
:cheers:
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Re: Headlamp Actuator Help Wanted! (74-Roadster)
Allrighty then.....I disconnected the rod end of the actuator from each of the headlight assemblys, then I disconnected one vacuum hose at a time from each actuator, plugging the hose and attempting to move the rod in/out. I encountered resistance/vacuum from each port when I tried to move the rod end. Does this mean the main diaphragm is okay, but the shaft seals need to be replaced? I believe I will take your advice and remove the entire hood, as it seems to be a tight fit in there, and I don't need to drive the car at the moment.
Thank you for your help, again
Thank you for your help, again
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Le Mans Master
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From: Fort Worth TX
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Re: Headlamp Actuator Help Wanted! (Trevelisek)
Allrighty then.....I disconnected the rod end of the actuator from each of the headlight assemblys, then I disconnected one vacuum hose at a time from each actuator, plugging the hose and attempting to move the rod in/out. I encountered resistance/vacuum from each port when I tried to move the rod end. Does this mean the main diaphragm is okay, but the shaft seals need to be replaced? I believe I will take your advice and remove the entire hood . . .
Taking the hood off is a good idea, might as well clean and paint the underside while your at it . . . :lolg:
