Here's my first DIY on the CL forum. Sadly I didn't take as many pictures as I should have but its not a complicated job.


I just bought a 1999 RX300 with 156,000 miles. Its in pretty clean condition but there are the typical annoyances like the rear hatch latch that won't reset once you open the rear hatch. In a nutshell, the axle that the latch pivots on gets gummed up with lube and years of dirt. The bad news, the bracket is steel and is rusty. The good news, the lever is plastic and the axle is galvanized/coated steel so its NOT rusty. The spring is fine as well. So it can be rehabbed.


First step is to remove the interior panels and there are two of them. Just yank them straight back and the rivets pop off. Nothing to fear here.


Next step is to identify the fasteners that hold the fascia on above the license plate and there should be 6 - 10mm nuts on studs in a line where the fascia is positioned (2 on the lock cylinder). Here's where it got stupid for me. The center 2 nuts came off nicely. The others were rusted and seized and just spun. The good news, when it spun it freed itself from the fascia. The 3 nuts in particular were the 2 on the lock cylinder and the far drivers side holding the fascia. Nothing life critical. The picture below are the fasteners to locate. (Red are push pins and the yellow are 10mm nuts)

Edit: there are 3 nuts (far left, both sides of latch) and 2 bolts (both sides of the lock cylinder)







At this point you would think the fascia would fall off but no. There are two small plastic push pins that hold the fascia on so you can secure the nuts during assembly. You will need to squeeze them fro inside so they clear the hatch. There is one by the 2nd from the left nut and one on the other side. Below picture with yellow arrow.





Once you remove the fasteners, the fascia will come off and dangle on the license plate lighting wires. The latch is now only held in place with plastic push washers which you will need a flat screwdriver to finagle off the studs. There are no mechanical cables to attach to the latch. It has a simple thumb lever that activates the actual latch inside the hatch panel. So the lever simply lift off the fascia. And this is what I found. A rusty gunked up lever. Don't lose heart, it can be cleaned up and made to function again.





You will need a steel bristle brush or similar brush and some solvent. Since the lever is out of sight, I just used non-chlorinated brake cleaner but for you purists amongst us, pick your preference. Don't just hose it all down. Be careful and try to just hit the axle and spring. Wet it and scrub it, wet it and scrub it until is freely movable again. I sanded some of the rust from the bracket and hit it with a little rustoleum to slow its death march but its not essential. But once you clean it thoroughly you will need to re-lube the axle. I used silicone spray lube. I find that Lithium grease just make a caked mess and dries out too quickly. Again, pick your poison. That's all there was to it. Reassemble the hatch and check for function.

 

Thank you.

Please dont forget to add a pointer link to this thread in the DIY sticky.

Salim

 

My sticky latch was irritating me, so I fixed my sticky hatch latch a couple weeks ago and had some pictures to share. Thanks Drcoffee for the writeup. For the future there are only 5 10mm nuts on studs not six. On my RX300 the two 10mm nuts on the far left (passenger side) and the one on the right (driver side) were rusted out.

Here is the picture facing up towards the latch.




Rear latch facing up.

This is the latch mechanism. I freed it from rust by rotating the metal rod which had developed a rust layer against the plastic component.



Rear latch mechanism

 

A BIG THANKS to both Drcoffee and coomassie for the great instructions. I just finished snapping back the interior panels on a successful fix.

The trick to loosen up the mechanism that worked for me was first realizing the buildup is not between the spring and axle, nor the rod and plastic component; but it is caused by the increase of thickness to the bracket (from all the rust) basically pinching the plastic component between the left and right sides of the bracket.

I used some Pepsi Cola solvent and an old Stainless Steel BBQ brush and scrubbed out the layer of rust built up, thereby recreating the original gap between the plastic component and the left /right side of the bracket. Luckily my BBQ brush also had a very thin metal scrapper at the end, which I was able to fit between the plastic component and bracket and really get out the rust, saving me about 20 minutes of scubbing. I also scrubbed the rust away from outsides of the bracket at the rod connections, and rotated the rod within the bracket like coomassie did above.

After it was al freed up, I finished scubbing off the rust, and used some MAF cleaner to clean off the Pepsi. I figured if the MAF cleaner was safe enough for the plastic MAF housing, it should be safe enough for the plastic latch. After the MAF dried, I coated the bracket with some Rustoleum Rust Reformer. After that dried, I lubricated the spring/rod/ bracket ends and put it back together. Works great.

I hope my explanation on where to clean out the rust was helpful. If my details were not clear enough, review coomassie's picture above where he is rotating the rod. The rust that needs to be scrubbed out is where the gap should be between the end of the plastic and bracket (just on the other side of the bracket from where he is grabbing the rod with the channel locks).

 

Just to be clear, the steel axle does not and should not rotate in the bracket. The rotation is between the plastic handle and steel axle. Its good to clean up the bracket, but its not where the problem lies.

 

Oh, I agree the stainless steel axle does not need to rotate, it just helped break free the rust buildup between the bracket and ends of the plastic mechanism. I also agree it is not necessary to clean the rust off the bracket, with the exception of where the plastic is scraping up against the bracket on each end.
It was the rust buildup on my latch bracket which was not allowing the plastic handle to rotate about the axle. As soon as couple of big pieces of rust were dislodged, it recreated the gap between the plastic and rusty bracket, and then the handle was free to rotate around the axle. At least on my latch, there was minimal build up on anything on the stainless steel spring/axle. Look forward to everyone insight and assistance on our other RX community issues.