Trunk Lock Questions
 

Hi everyone:

Yesterday, I found out that neither of my black keys will fully insert into the trunk lock. They do work with the steering column and the door. Before I start spending money to fix this, I'd like to hear your suggestions.

1) Could a locksmith tell me why the key may not insert fully.

2) Would spraying a lubricant like WD40 into the cylinder possibly free up the mechanism and allow the key to go in all the way.

3) More importantly, if I decide to replace the lock cylinder, which seems like an easy DIY, do I need to buy a cylinder that matches the cut of my key or are they just generic parts.

4) Once replaced, would anything need to be programmed. As mentioned, the black keys already work in the ignition and door.

It seems like this is an important thing to fix in case the battery dies and I need access to the trunk.

Thanks

Thom

I think this is quite common if the boot (trunk) lock is not used for a long time. I would spray WD40 or similar into the lock and then gently keep trying the key until it inserts fully and turns.

Just WD40, and some time, will do the trick, slowly work it loose.
Even if the key works fine, it needs a bit of force on the last 45 degrees (full unlock is ~90 degrees), but don't over do it till you are sure it came loose.
After that, let it dry, then spray it with graphite for long lasting lubrication.

If loads of WD40 and time won't do the trick, then you can remove the whole trunk lock assembly and try to free it up on the workbench. No special tools needed except of a heat gun.
When removing note the orientation of the lock assembly itself and of the link bar, which connects to the lock mechanism.

To remove the lock cylinder from its housing the snap ring at the back of the plastic element (fig. 1) has to go. Then you can remove the plastic element itself and the trunk cylinder should slide out of the front of the lock housing.
If it doesn't then you can try slightly tapping the cylinder from the back. And/Or heating up the front of the trunk assembly (where the key is inserted). The weak point of the construction is the contact zone of the polished steel cap (with the key hole) and the aluminium housing. Having water in this area will lead to galvanic corrosion building up between the two dissimilar metals. This kind of corrosion contains a lot of (chemically) bound water which takes plenty of space so that the cylinder can't be turned anymore. If the corrosion is already quite severe then even soaking in WD40 for days won't help.
Heating up that area will evaporate the incorporated water and therefore shrink the corrosion a bit so that you can remove the cylinder from the housing and give it a thorough clean. There are no plastic or rubber parts in the cylinder so that you can give it a decent treat with the heat gun.
Fig. 2 shows how much debris has been build up at the front of the cylinder. There had been no significant other signs of corrosion anywhere else in the lock - just at the front.
I cleaned all parts, re-greased them and gave the aluminium housing a quick respray, so that the corrosion won't come back very soon. From time to time I'll unlock the trunk using the key just to prevent any failure once again.


https://cimg0.ibsrv.net/gimg/www.jag...264bbeba50.jpg
fig. 1
https://cimg2.ibsrv.net/gimg/www.jag...bc16e1a4a2.jpg
fig. 2
https://cimg3.ibsrv.net/gimg/www.jag...c1782dc5dd.jpg
fig. 3

Hi all:

Problem solved for me at least.

Given your detailed suggestions, I decided to travel down the spray/lubricate road first. Before doing so, however, I decided to visit the local locksmith to see what they would recommend. They sprayed the 'frozen' lock with a product called TriFlow. After a few sprays and a few moments jiggling the key in the lock, the key slid in fully and turned. Whoopee, the trunk popped open.

I mention this because they warned against the WD40/graphite approach. They said the combination would work initially, but eventually it would clog the lock. So I bought a small can of TriFlow from them and it now sitting on the workbench for future use. Apparently, its a teflon based cleaner lubricant.

Regards

Thom

great info thanks

great thanks

Speaking specifically to door lock lubricants, most locksmiths that I have dealt with show disdain to the WD-40 brand.
That being said, there is the which has proven itself to be my lock lubricant of choice
There is documented testing which shows the PTFE spray outperformed the standard locksmith-recommended door
lock lubricant,,,, Tri-Flow. The testing showed that the lock cylinder and pin chambers remained cleaner, and the spray
made more significant improvements to the lock’s functioning in an overall fashion.

Thanks

According to this label it is formulated with ptfe
https://cimg9.ibsrv.net/gimg/www.jag...7387a8c1b8.jpg
According to this label it is formulated with ptfe

I had to look it up... PTFE is Polytetrafluoroethylene and is apparently "a synthetic fluoropolymer of tetrafluoroethylene" for whatever that means. :)

Discovered by Dupont in 1938, the most common brand name today is Teflon.

Apologies to those who already knew this.

Thanks

When some of you who have taken this lock apart do you know the purpose if that roll pin that lays in that Grove.

Thanks