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Door Latch/Lock Woes

Contributed By: Michael Baxter

A common trouble source on FSJs of all ages is a small spring in the door latch mechanism that breaks with wear and creates a symptom in which the door lock knobs won't stay in the up or unlocked position.

Another common problem is the door latch release handle mechanism's coil spring also breaks making it nearly impossible to open the door from the inside. This How To will also cover removing it for replacement by following the procedure up to that point.

There are two types of latches on '74-'91 FSJs. Type 1 latches which appear mostly round when viewed at the rear of the door itself with the door in the open position. Type 2 latches have a short lever with a crescent shaped notch. Each type has correspondingly different catch mechanisms on the body. It is important to obtain the correct latch if you decide to replace the whole latch. FYI, Type 1 latches are no longer available from the dealer.

You have two choices. You can either replace the whole latch or you can replace just the broken spring with a good spring salvaged from a donor latch. FSJ latches are painted body color during production. If you decide to obtain your donor latch at a junk yard (req'd if you have Type 1 latches) and you want to replace the whole latch, try to obtain one from a FSJ painted the same color as yours. Otherwise you'll need to paint the exposed part of the new latch to match or live with the color mismatch. Of course, if you decide to do the extra steps (outlined below) and replace just the spring; you won't have to worry about color mismatch.

It's not difficult to get the latch out. Practice at a self-service junk yard extracting a donor latch before you work on your own if you can.

Tools and materials possibly req'd:

-. 5/32" Allen wrench
-. 1/8" flat blade screwdriver
-. #2 Phillips screwdriver
-. Automotive trim puller tool
-. Large needle-nose pliers
-. Small needle-nose pliers
-. T-25 Torx screwdriver/bit
-. 3M automotive caulk
-. Thick plastic sheet
-. White lithium grease
-. Med. size locking pliers

- Roll the window all the way up.

- Unscrew the door lock knob at the base of the window and remove.

- Remove window crank (if equip'd) and door latch release handles. (Note for reassy.: there should be plastic anti-wear discs behind each handle)

- Remove two screws from the bottom of the padded door handle trim if equip'd.

- Unscrew two large screws and remove the padded door handle (Note for reassy.: the screws fasten via two large speed clips. They like to fall into the bottom of the door on reassy. and can require you to remove the door trim again to recover the clip(s). Once the door panel is removed, I retain the clips by using a flexible caulk such as the 3M auto. caulk or a door/window type butyl caulk like the factory.).

- Remove the automotive trim screws at the bottom of the door panel.

- Use the trim removal tool to remove the push fasteners along the sides of the door panel by prying between the door frame and the back side of the panel. Place the tool between the metal door frame and the large plastic disc. part of the fastener. Not between the disc and the back side of the trim panel which will ruin the door panel where the fastener attaches. Two large flat blade screwdrivers and a rag to keep from marring the paint could be substituted for the trim tool if you're very careful.

- Remove the door panel by pulling it out at the bottom until the door latch release's splined shaft and window regulator's splined shaft (if equip'd) are clear and then pull down.

- Remove the water-shield sheet (paper backed rubber sheet behind the door panel) as carefully as you can. It will most likely be all crinkled-up and in need of replacement. I'll provide the procedure optionally at the end of this one.

- Electric window/door lock FSJ DIYers disconnect associated wiring (I don't have elect. windows so, can't help here)

- Manual remote mirror control cables are long enough (at least on '7X FSJs) that the door panel can be maneuvered such that it sits on top of the steering column between the steering wheel and the dashboard with the cable still attached.

- Find the black plastic disc(s) (might be stuck to the back of the door panel) that are normally installed over the latch release/window regulator shafts between the door frame and back of the trim panel. These seal out cold air. (Reassy. Note: Don't forget to reinstall it/them before putting the panel back on.).

- On the rear edge of the door frame, remove the two plastic rivets which secure the foam rubber filter/seal thingie (normally rotted away) covering the lock cylinder retainer clip. The retainer clip is located just outside and slightly above the exposed part of the latch on the rear of the door frame right next to the spot welded lip formed by the outer door skin and the frame. If your still wondering where the clip is put your finger on the key cover where the key is inserted to unlock the door, move it straight back along the door skin and then hook your finger around the lip at the back of the door. The clip is right there.

- Pull the clip using the locking pliers or large needle-nose pliers to hang onto the rolled edge of the clip. The clip has two retaining tabs which just fit through the slot for removal. You'll have to position the clip exactly in the center of the slot to remove it by moving it up or down while pulling rearward until the retaining tabs are through the slot.

- Remove the three screws (9, 12 & 3 o'clock positions) around the door release mech's. splined shaft. Push the mech. into the door while jiggling the linkage rod that attaches to the latch mech. (Reassy. Note: The linkage rod attaches to the release mech. above the splined shaft. You can spend a long time trying to get that thing back through the hole.)

- Let the release mech. drop into the bottom of the door. If you have a speaker in the door, make a futile attempt to keep it away from the magnet where it could put holes in the plastic sheet protecting the speaker from water damage.

- Locate the plastic grommet which secures/guides the "U" shaped door lock link rod. It's located beneath the latch mech. and is easily accessible through one of the access holes. Using a large needle-nose pliers, push the plastic grommet up from the bottom to release it from the bracket. You'll need to hold the pliers just open enough to straddle the linkage rod while you push up on the bottom of the grommet.

- Remove the 3 T-25 Torx screws (possibly Phillips on earlier FSJs) around the exposed part of the latch mech. at the rear of the door to remove the latch.

- Then maneuver the latch downward until the lock link rod's threaded end is clear of the hole at the base of the window. Work the latch, w/ both linkage rods attached, out through the large access hole at the bottom of the door.

- Follow the flat release linkage rod to where it attaches to the door latch mech. Note the spring loaded washer which is retained by a small tab on the linkage rod. On the door latch mech. at the point where the release rod attaches, just outside of the spring loaded washer, is a rectangular tab which corresponds to the rectangular cut-out in the end of the door release link rod.

- Rotate the flat link rod down until the rectangular tab aligns with the rectangular cut-out in the end of the rod.

- Then push out on the rod such that the tip of the link rod moves closer to the latch mech. and then push the rod toward the latch mech. (the linkage rod is normally only pulled away from the latch mech. when you pull-up on the door latch release this step you need to push it toward the latch opposite of its normal action). The link rod should release with this compound motion. The object is to get enough clearance between the spring loaded washer and the small retaining tab for the washer to over-ride the tab when you push the rod toward the latch. Keep in mind the rectangular tab has to be aligned with the rectangular hole.

Reattaching the link rod to the post is as easy as aligning the rectangular tab with the rectangular slot in the rod end, pushing them together against the spring loaded washer, rotating the link rod a little to offset the tab and the slot and pulling the link rod away from the latch. You should hear a click when the spring loaded washer locks down in front of the small tab.

Note for reassy.: On some door latches; the whole spring loaded washer, post and rectangular tab will rotate rather freely. This was not intended in the original design. In this case, the rectangular tab should be aligned almost vertically when the latch mech. is held orientated as installed in the door. You should rotate the post until the tab is almost vertical after the link rod is attached. After reinstalling the latch and link rods back in the door, peer through the lock cylinder hole from the outside of the door and make sure the rectangular tab is still orientated near vertical.

- Holding the latch mech., note the "U" shaped lock linkage rod is inserted into the hole on the lock lever from the outside (in reference to how it is oriented when mounted in the door). Unhook the rod.

Note on the other side of the lever you just unhooked the lock linkage rod from is what is left of a small 2 turn over-center spring. This is the culprit. You can see the the metal wear on the lever where the spring slides. This wear eventually causes the spring steel to break.

At this point, you can swap your latch with the donor latch completely and then follow the steps above in reverse order for reassembly. I recommend you give your replacement latch a through solvent bath and then lube everything liberally with white grease. Especially lube the area where the over-center lock lever spring rubs on both the latch body and the lock lever.

If your water-shield (paper backed rubber) sheet is in sad shape as mentioned earlier, I'll outline a procedure for it at the end of this How To.

Here's my procedure for replacing the spring itself:

Examine the spring configuration closely on your donor latch. Notice one end of the spring passes straight through the hole on the lock lever, but the other end of the spring passes through the hole on the latch body and is folded over at a 90 degree angle.

The object will be to straighten the 90 degree bend a little and pry the body and the lever far enough apart to remove the spring. Normally spring steel used in springs can't be bent easily. In this case the material is such that some bending is feasible.

- Using a flat blade screwdriver, pry between the lock lever and the latch body and bend the lever out just a little. You're trying to open up the clearance between the two just enough to facilitate removing the spring, so don't over-do this step. You can always open them up a little more later on.

- Straighten the 90 degree bend with the small needle-nose pliers just enough, in your judgment, that you can maneuver the end of the spring out through the hole. If I remember correctly, I was able to do it with about a 45-60 degree angle.

- Now using the small needle-nose, push the straight end of the spring out through the hole in the lock lever as far as you can. You'll be restricted when the spring contacts the latch body.

- Then grab the straight end on the other side of the lock lever and pull it out of the hole. You may need to pry between the two some more with the screwdriver, but no more than it takes to pull the spring out.

- Now grab the 90 degree end of the spring between the lock lever and the latch body using the small needle-nose pliers again. Work that end out of the hole now. If you have any trouble, you may have to straighten the bend some more.

- Install the donor spring onto your latch mech. in reverse order of above. I recommend you give your completed replacement latch a through solvent bath and then lube everything liberally with white grease. Especially lube the area where the over-center lock lever spring rubs on both the latch body and the lock lever.

Here is the skinny on the water-shield:

The water-shield is an important part of keeping your FSJ's floor from rusting out. Water intrusion from behind the door panels is insidious and you may not notice until you push your foot through the floor one day. If your water-shield sheet(s) are questionable in any way, I recommend you make new ones.

I used 8 mil plastic sheeting and the backside of the door panel as a template to make new water-shield sheets for mine. Once I had the sheet cut out to fit the door with all the holes punched using hollow punches, I used 3M Automotive Strip Caulk to glue the plastic sheet to the door (not the door panel).

I have since seen a rubber like material that they use to back shower and bath tub walls in construction which I feel would be better. It's about 1/32 of an inch thick and seems perfect for water proofing a door panel. You can find the stuff in large home improvement stores (Home Depot) in the bath room fixture section. It comes on a 4 ft. wide roll and they sell it by the foot.

There are a couple of louvers at the bottom of the door. The original Jeep water-shield (paper-backed rubber) tucked into these louvers. You need to do the same with the plastic or rubber like stuff. Any water that gets between the door and the plastic backing will drain down and run back into the door through the louvers.

I applied caulk to the door in such a way that water is channeled to the louvers. There should be enough of the factory caulk left for you to be able to see the general pattern that Jeep used. The caulk line required at the front of the door runs at an angle down to the forward louver. If you have a speaker in the door, completely surround it with a circle of caulk (should also have a plastic shield behind the speaker). You can add an "arch" of caulk between the two louvers to keep water from going between the louvers. After the caulking is in place, carefully stick your newly fabricated water shield to the door. Then press the plastic firmly to every inch of the caulk line to ensure a complete seal.

It's a little time consuming to do all of this, but much better in the long run than living with the Fred Flintstone effect :-).

Corrections and comments gladly accepted.

Michael Baxter


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