Author Topic: **Door lock issues  (Read 1521 times)

laughoutlloyd8

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**Door lock issues
« on: 01 June 2011, 02:10 PM »
I'm hoping to find answers here, I have a 77' 450 SEL and my door locks seem to not be functioning.  I have to manually lock them myself.  Do anybody know how to fix this solution and how much will it cost? thanks

jbrasile

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Re: **Door lock issues
« Reply #1 on: 01 June 2011, 02:17 PM »
laughoutlloyd8,

Do a search and you will find tons of information on how to diagnose and repair non functioning door locks.

First step  is to get a little vacuum pump to test the various components and then be methodical in your checking procedures to isolate one part of the system at a  time.

Door lock diaphragms are available, you need 12, 4 per door, trunk and fuel door actuators however must be replaced if found to be deffective.

Tks,

Joe

1980sdga

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Re: **Door lock issues
« Reply #2 on: 01 June 2011, 02:24 PM »
Do you have a vacuum pump like this:



You may be able to troubleshoot it without it but you could end up chasing your tail.  Look up your car in the library on this forum and check out the vacuum diagrams for your application.  

It runs off engine vacuum which is stored in a reservoir in the trunk. Could be a leak running to it or any of the actuators in the doors, gas lid or trunk.  I believe that the "master" valve in the drivers door and the vacuum lines running to it are often at fault.  It could also be a leak at the bundle of lines in the engine compartment beside the brake booster.

If it's never been worked on then be very careful about swapping vacuum lines around. Try to keep everything the way it left the factory and replace components without getting anything mixed up.
Jon


Little by little I have grown fond of the infamous Auto Temp II we have in our 116's

Casey

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Re: **Door lock issues
« Reply #3 on: 01 June 2011, 07:15 PM »
Where do you find these vacuum pumps?  I'm definitely going to be needing one once I have a little more funds to tinker more on my car...

1980sdga

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Re: **Door lock issues
« Reply #4 on: 01 June 2011, 08:26 PM »
Where do you find these vacuum pumps?  I'm definitely going to be needing one once I have a little more funds to tinker more on my car...

I got mine at Sears. They had a metal one for about $50 and a plastic one for about $30. I got the plastic one (It's a MityVac brand) and it works fine.  I also found a regular vacuum gauge was pretty helpful.
Jon


Little by little I have grown fond of the infamous Auto Temp II we have in our 116's

Casey

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Re: **Door lock issues
« Reply #5 on: 01 June 2011, 08:31 PM »
Door lock diaphragms are available, you need 12, 4 per door, trunk and fuel door actuators however must be replaced if found to be deffective.

Hey Joe,

My door locks generally work for a short while after the car is turned off...but the rear driver-side door lock never goes down even though the others do, and there's *definitely* a leak in there because I can hear hissing if I sit in the car after turning it off and lock the doors.  I haven't investigated too closely but did notice what I guess is the diaphragm located in the bottom of the door last time I had the panel off.  It really doesn't matter that that door doesn't lock, because it also doesn't open from the outside, but at some point I hope to have it totally working.

Anyways my question for you is, from those symptoms, is it possible to accurately guess what part might need replaced?  Of course I will need to double check for something dumb like a hose come loose.  Would a broken vacuum part cause the door to be unopenable from the outside?
« Last Edit: 01 June 2011, 08:33 PM by Raptelan »

jbrasile

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Re: **Door lock issues
« Reply #6 on: 01 June 2011, 08:50 PM »
Hi Casey,

Yes, it sounds like you definitely have a major leak at the LR  door. Each door actuator has 4 diaphragms, 2 to lock (pull down) 2 to unlock (push up).

The diaphragms are available from George Murphy at Performance Analysis in Oak Ridge TN, I think last time I paid $8.50 a piece.

As for that door not opening from the outside, well if the actuator on that door is not working maybe it is sort of jammed  and preventing the door form opening using the outside handle. You can open it form the inside  right?

Another possibility is for the latch mechanism to be  stuck, with the door open, manually push the latch hook all the way to the closed position and actuate the external door handle while pulling on the hook with your hand. If you feel it is not releasing the lock, lube it with some WD-40 and then some white spray grease. Pay attention also if the handle itself seems to be " disconnected"  from the door mechanism. These handles have an adjustment so they " bite"  early or late and sometimes after many years that adjustment needs to be checked. To do that you have to remove the handle from the door.

Let me know how it goes.

Tks,

Joe