Door lock not working anymore

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Jelmer
Posts: 55
Joined: Wed Oct 31, 2012 11:01 am
Location: Netherlands

Door lock not working anymore

Post by Jelmer »

When we bought the E12 last year the LHS door lock was working good. After awhile it got harder to use, you had to fiddle around a bit. Eventually it did work at all anymore. You just can't turn the key anymore.

Any advice how to fix this? We would like to keep 1 key for everything.
'76 E12 528, stock
'84 E28 538i, S38B38
'84 Nissan Patrol 2.8i

'79 E12 524TDa, sold!
GripGreg
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Joined: Tue Jan 06, 2009 1:50 pm
Location: Long Beach, Cal.

Post by GripGreg »

Try lubricating both doors with the spray graphite that comes in a little tube.
I have to do the same to mine.
After spraying, push & pull the key in & out about five times to distribute the graphite before turning & cross your fingers. :wink:
I believe it'll get easier gradually.
Graphite may leave some residue on the key in the beginning, so, a wipe down may be in order at first.
Rosallina/'80 528i
Buster/'82 635Euro
Hit the apex in Long Beach
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Mike W.
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Location: Sonoma County

Post by Mike W. »

Graphite is old school and not used by any locksmiths I know. Here in the states we have a great spray lubricant, with teflon, called Triflow that is absolutely great in locks. Not WD40, which does not. It's also relatively expensive, but not too bad and goes a long ways. Look for that if you feel it's the key part of the lock. But the mechanism also gets stiff, and it is winter, and grease, especially old grease can turn to glue when it gets cold. For that you have to take the latch mechanism out, clean and relube it.
Mike W.



02 525ita. Wife's, aka grocery getter
02 530i. New to the fleet, 3 pedals.
03 QX4, AKA the Datsun. Finally got the 4WD vacationmoble to stop smoking.
07 Xterra. Still on the DL, a purchase from hell.
Jelmer
Posts: 55
Joined: Wed Oct 31, 2012 11:01 am
Location: Netherlands

Post by Jelmer »

Thanks guys!

Ik think I'm going to take the whole mechanism out, soak it in my degreaser and relubricate it. I did this to the electric window mechanism of my E28 (which where very slow up and down) and relubrucated everything. The window now runs very quick up and down, just like new!

But the lock feels like it is blocking so there might be a different problem.

I let you guys know!
'76 E12 528, stock
'84 E28 538i, S38B38
'84 Nissan Patrol 2.8i

'79 E12 524TDa, sold!
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John in Simi Valley
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Location: Formally Simi Valley, Ca.

Freeing up the door locks

Post by John in Simi Valley »

Here is a FAQ for getting to the door lock linkage.
I've found that it has more to do with the lock mechanism linkage seizing up because of old dried out grease than the lock itself.

The following link will help you gain access to these areas.
Spray the link joints with something that will soften up the hardened grease and then actuate the mechanism to get the joints to operate with less restriction.

Have fun!
http://firstfives.org/faq/door_panel_re ... moval.html
John Savage
1980 528i 5-Speed
FirstFives COTM Editor
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