Help trouble shooting Headlights!!!
Thread Starter
Intermediate
Joined: Nov 2012
Posts: 37
Likes: 0
From: Summerville SC
Help trouble shooting Headlights!!!
Hey guys,
I'm rebuilding my headlight assembly and adding new bulbs, ect. The passenger side lights would come up slowly and over a period of time would not come up at all. Thinking it might be the actuators, I went ahead and replaced both of them. I still have the same problem. What do you guys think? Relay? Hoses look good.
Janton
I'm rebuilding my headlight assembly and adding new bulbs, ect. The passenger side lights would come up slowly and over a period of time would not come up at all. Thinking it might be the actuators, I went ahead and replaced both of them. I still have the same problem. What do you guys think? Relay? Hoses look good.
Janton
Drifting
Joined: Jul 2006
Posts: 1,259
Likes: 154
From: Deplorableville Nebraska
Assuming your new actuators are good, the relays are your problem. You can test them before you throw more money at your problem fairly easily.
Mark your relay hoses and disconnect the lower and middle relay hoses. Using a short test hose, hook it up to the middle relay port. While blocking the lower port with your finger, try to blow through the relay. You should not be able to do this. If the relay leaks doing this test, the internal piston seal is shot.
If the relay(s) are bad, do not throw them away if they are original. They can be rebuilt. Also, before you spend good money on new ones, make sure the vendor checks the relays before they ship them, like Wilcox does.
Mark your relay hoses and disconnect the lower and middle relay hoses. Using a short test hose, hook it up to the middle relay port. While blocking the lower port with your finger, try to blow through the relay. You should not be able to do this. If the relay leaks doing this test, the internal piston seal is shot.
If the relay(s) are bad, do not throw them away if they are original. They can be rebuilt. Also, before you spend good money on new ones, make sure the vendor checks the relays before they ship them, like Wilcox does.
Thread Starter
Intermediate
Joined: Nov 2012
Posts: 37
Likes: 0
From: Summerville SC
Thanks Dave!
Thanks Dave! Question...If I swap relays, won't the problem follow to that side? I tried that and only the driver side still comes up and not the passenger side. Same problem.
Assuming your new actuators are good, the relays are your problem. You can test them before you throw more money at your problem fairly easily.
Mark your relay hoses and disconnect the lower and middle relay hoses. Using a short test hose, hook it up to the middle relay port. While blocking the lower port with your finger, try to blow through the relay. You should not be able to do this. If the relay leaks doing this test, the internal piston seal is shot.
If the relay(s) are bad, do not throw them away if they are original. They can be rebuilt. Also, before you spend good money on new ones, make sure the vendor checks the relays before they ship them, like Wilcox does.
Mark your relay hoses and disconnect the lower and middle relay hoses. Using a short test hose, hook it up to the middle relay port. While blocking the lower port with your finger, try to blow through the relay. You should not be able to do this. If the relay leaks doing this test, the internal piston seal is shot.
If the relay(s) are bad, do not throw them away if they are original. They can be rebuilt. Also, before you spend good money on new ones, make sure the vendor checks the relays before they ship them, like Wilcox does.
Thread Starter
Intermediate
Joined: Nov 2012
Posts: 37
Likes: 0
From: Summerville SC
OK…tested using your method with the short hose. Both relays are good! I could not get any air through, blowing into the middle (yellow) while blocking green with my finger. (red ports and metal ports not connected and open)
Ideas? Can?
Ideas? Can?
Assuming your new actuators are good, the relays are your problem. You can test them before you throw more money at your problem fairly easily.
Mark your relay hoses and disconnect the lower and middle relay hoses. Using a short test hose, hook it up to the middle relay port. While blocking the lower port with your finger, try to blow through the relay. You should not be able to do this. If the relay leaks doing this test, the internal piston seal is shot.
If the relay(s) are bad, do not throw them away if they are original. They can be rebuilt. Also, before you spend good money on new ones, make sure the vendor checks the relays before they ship them, like Wilcox does.
Mark your relay hoses and disconnect the lower and middle relay hoses. Using a short test hose, hook it up to the middle relay port. While blocking the lower port with your finger, try to blow through the relay. You should not be able to do this. If the relay leaks doing this test, the internal piston seal is shot.
If the relay(s) are bad, do not throw them away if they are original. They can be rebuilt. Also, before you spend good money on new ones, make sure the vendor checks the relays before they ship them, like Wilcox does.
Drifting
Joined: Jul 2006
Posts: 1,259
Likes: 154
From: Deplorableville Nebraska
Next you need a "T" connector to put your vacuum gauge in series with the vacuum hoses. Connect it between the suspect actuator and the relay. The reading should be the same as your engine's vacuum reading.
Next, I use a needle nose vice grip pliers to pinch closed the vacuum line between the gauge and the relay before you turn the engine off. You should NOT observe any vacuum loss after shutdown.
Next, I use a needle nose vice grip pliers to pinch closed the vacuum line between the gauge and the relay before you turn the engine off. You should NOT observe any vacuum loss after shutdown.
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Thread Starter
Intermediate
Joined: Nov 2012
Posts: 37
Likes: 0
From: Summerville SC
When you do this test, should doors be up or down? Do you put the gauge in series on the green line or red line? Or does it matter?
Next you need a "T" connector to put your vacuum gauge in series with the vacuum hoses. Connect it between the suspect actuator and the relay. The reading should be the same as your engine's vacuum reading.
Next, I use a needle nose vice grip pliers to pinch closed the vacuum line between the gauge and the relay before you turn the engine off. You should NOT observe any vacuum loss after shutdown.
Next, I use a needle nose vice grip pliers to pinch closed the vacuum line between the gauge and the relay before you turn the engine off. You should NOT observe any vacuum loss after shutdown.
Drifting
Joined: Jul 2006
Posts: 1,259
Likes: 154
From: Deplorableville Nebraska
I do have a mityvac…yes
Next move the headlights down one at a time. Put the Mityvac on the rear port of the actuator, and pump it up. It should hold vacuum. Do this to each side.
This is the best test of the actuators. If they test OK, you can move to the next test.
Thread Starter
Intermediate
Joined: Nov 2012
Posts: 37
Likes: 0
From: Summerville SC
OK…we are on to something!
OK Dave…I think we have something! 
Drivers side (the one that works when all hoses are hooked up) = Closed the light, removed all hoses, hooked minivac up to where the green connects on the actuator (bottom)….the headlight raised! Hooked mini vac up to the top port where red connects….the light closed!
Passenger side (the one not working)…did the same test as above…nothing. The light did not close or open.
Bad actuator? What do you think?? It's brand new? How could this happen???
Drivers side (the one that works when all hoses are hooked up) = Closed the light, removed all hoses, hooked minivac up to where the green connects on the actuator (bottom)….the headlight raised! Hooked mini vac up to the top port where red connects….the light closed!
Passenger side (the one not working)…did the same test as above…nothing. The light did not close or open.
Bad actuator? What do you think?? It's brand new? How could this happen???
Good! Forget the vacuum gauge for now. Keep the engine off. Pull the actuator hoses off front and back. Pull the headlight up one at a time, and connect the Mityvac to the front actuator port. Then simply pump it up. It should hold vacuum. Do this to each side.
Next move the headlights down one at a time. Put the Mityvac on the rear port of the actuator, and pump it up. It should hold vacuum. Do this to each side.
This is the best test of the actuators. If they test OK, you can move to the next test.
Next move the headlights down one at a time. Put the Mityvac on the rear port of the actuator, and pump it up. It should hold vacuum. Do this to each side.
This is the best test of the actuators. If they test OK, you can move to the next test.
Drifting
Joined: Jul 2006
Posts: 1,259
Likes: 154
From: Deplorableville Nebraska
OK Dave…I think we have something!
Drivers side (the one that works when all hoses are hooked up) = Closed the light, removed all hoses, hooked minivac up to where the green connects on the actuator (bottom)….the headlight raised! Hooked mini vac up to the top port where red connects….the light closed!
Passenger side (the one not working)…did the same test as above…nothing. The light did not close or open.
Bad actuator? What do you think?? It's brand new? How could this happen???
If you still have your old actuators, check them. Check the rear ports first. If you have a good one, then check the front port. Remember, front seals can be easily replaced.
Good luck........Dave
Team Owner
Joined: Jul 2004
Posts: 40,404
Likes: 791
From: Redondo Beach, California
I bought new repro vacuum actuators for my headlights, only because they looked new. About three years after installation, one of them stopped working due to leaky seals. I replaced it with one of the original vacuum actuators which, of course, still works fine.
Repro stuff!!!
Repro stuff!!!
Advanced
Joined: Apr 2014
Posts: 66
Likes: 4
From: Alvin, Texas
Good info. I am having similar issues with my right side. I'm about 95% sure there is a leak up front that is effecting my #4 and #8 cylinders. Plugged off the hose to the engine and cars runs very good. With vacuum hoses hooked up correctly, car runs rough off the start. There is another thread here about the engine running lean I placed that describes all the preliminary test that were done prior to this determination.
Replaced all the vacuum lines up front so I know they are good. I purchased new actuators but have not installed them yet. Want to test the relays first, hope to do that this week. Almost to the point of replacing all so everything is new but after reading a few post, I see there is a chance the new parts could leak as well. Going to try to do the test this week-end and see what I come up with. Any other suggestions are welcome. Will let kyou guys know how things turn out. Thanks.
Replaced all the vacuum lines up front so I know they are good. I purchased new actuators but have not installed them yet. Want to test the relays first, hope to do that this week. Almost to the point of replacing all so everything is new but after reading a few post, I see there is a chance the new parts could leak as well. Going to try to do the test this week-end and see what I come up with. Any other suggestions are welcome. Will let kyou guys know how things turn out. Thanks.
Thread Starter
Intermediate
Joined: Nov 2012
Posts: 37
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From: Summerville SC
I like happy endings as well! :agree:
Now this is happening….Just re-did the doors…new regulators, new motors, new power lock motors ands switches, new pig tails, new panels…the works! Got everything buttoned up and cool all in the world is fine!!! 2 days later, boom…all of a sudden, no windows! When I work the center console switches, it's drawing power (lights dim), so I know power is to the switches…took off the door panel and checked the motor wires with my multimeter…power there…positive and negative (reverse polarity) when flipping the switches. Replaced the 30amp 12 CB. No Dice! Still the power draw on both sides when working the switch. (power dim).
So….what am I missing? I'm totally out of ideas! Everything was working great…then both went out at the same time….
Now this is happening….Just re-did the doors…new regulators, new motors, new power lock motors ands switches, new pig tails, new panels…the works! Got everything buttoned up and cool all in the world is fine!!! 2 days later, boom…all of a sudden, no windows! When I work the center console switches, it's drawing power (lights dim), so I know power is to the switches…took off the door panel and checked the motor wires with my multimeter…power there…positive and negative (reverse polarity) when flipping the switches. Replaced the 30amp 12 CB. No Dice! Still the power draw on both sides when working the switch. (power dim).
So….what am I missing? I'm totally out of ideas! Everything was working great…then both went out at the same time….
Safety Car
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From: Madeira Beach, FL
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Dave just finished up helping me a month or so ago.
My problem was a defective new P/S actuator I assumed was good.
I purchased them over the winter of '14 on Ebay from a vendor.
They didn't last.
Orig. is the way to go.
Relays work great Dave by the way.
Thanks,
Marshal
My problem was a defective new P/S actuator I assumed was good.
I purchased them over the winter of '14 on Ebay from a vendor.
They didn't last.
Orig. is the way to go.
Relays work great Dave by the way.
Thanks,
Marshal