Hey guys. When I purchased my 1984 928, I knew the rear hatch had been monkeyed with by the PO. He said it would pop open when doors slammed or bumps were hit hard. He had some shims and suspect looking stuff going on.

Upon further inspection............plastic latch on the upper lock was worn, the housing was cracked and the lower latch wea missing the rubber insert.

So I figured, drop the money and replace it all!!!!
Roger at 928r us got me set up and I installed both pieces.

But the latch will still not close

It looks like the top latch is not pushing the plunger on the bottom latch far enough down to pass the plastic lip and catch?

Does that make sense? I thought maybe I am missing some part like a rubber foot or gasket for the latches. But it seems according the PET6 I have it all?

What are my missing here? Adjustment?

Pleaseeeeeeeeeeeee help!

Shawn
84' 928
74' TR6

 

My son's 80 model acted the same way. His hatch had migrated downhill over the years about 3/16" so I readjusted the hatch UPHILL as much as possible and it not only fixed the latch but it sills better and is quite as can be.

I have also used heavy duty Velcro to pad that latch to minimize squeaking at that rub point.

 

Thanks Dean.

When you say migrated downhill, I am not sure I understand what that means? How do you re-adjust the hatch?

Also velcro pad on the bottom latch or top?
And where did you apply such a pad.

Also...............are these the rubber bumpers that can be adjusted to raise and lower how high the hatch sits?

Do mine look like they are put on right?

I removed them and the hatch seemed to sit better, but still is not locking, so I put them back on.

It still looks like the top latch is just not inserting deep enough into the bottom latch.

 

Not sure if this is a known adjustment and wanted to share a recent similar situation.

The rear hatch system worked great (verses the drivers door lock, hel) when I delivered car to painter. The painter removed rear hatch to paint and re-installed. He alerted me that he could not get the hatch to close and asked for ideas, (wtf, now rear hatch and drivers door also!).

When I visited car, we looked at rear hatch mechanism (and it worked perfect prior to removal) then I noticed that the gap between the rear hatch and the roof of the car seemed wider than I remembered. I could see the rear hatch hinges more than before. I suggested sliding the rear hatch up to close the gap between hatch and roofline (approx. 1 to 2 millimeters), and the rear hatch was in harmony again!

 

Shawn,
Take off the 2 rubber adjutment blocks and see if that makes any difference.
They should be set to just kiss the hatch when closed and locked.
There are also 2 small rubber buffers at each corner at the rear.
Make sure they are not stopping the hatch closed either.
Roger

 

There are no rubber feet or gaskets under the receiver. Some cars have spacer plates under the receiver to raise it. I wouldn't worry about that. I would turn the rubber bumpers on the rear corners of the hatch all the way in and see if it will latch. With new upper and lower latch parts, this is often required. The turn the bumpers out just enough to so there are no rattles. With everything just right and new parts, the hatch release will not need to "pop" loudly as it releases like you commonly see in cars that have an over-snugged the latch by setting the rubber bumpers too far out, trying to eliminate hatch rattles. Make sure all the rubber surfaces are lubed with VERY light coat of silicone grease (Sil-Glyde or Super Lube Synthetic Grease) and pop the hatch shocks off and lube the ball mounts.

One other possible cause is that the release motor has stopped in the position that has the release cam pushing on the tongue, not allowing it to latch. Check the position of the drive arm on the motor at rest. The drive arm should be at it's highest point and the release cam should be retracted away from the tongue. If the arm is correct, but the release cam is not retracted, adjust the position of the motor until it is (2 M6 bolts on the front facing side of the receiver).

 

I will try that Roger.

The rubber buffers at each corner are not adjustable are they?
It does seem that if the hatch was slid back just a bit, like suggested in the previous post, that could also be a potential fix. How is that done? Mounting bolts on the hindge, loosened and then slide the hatch back a hair?

Like I said it seems that the upper latch is not pushing deep enough to catch the plastic lip on the bottom, but it could also be that the upper lock is sitting to far back to catch?

The upper and lower latch do fit together. If it is the hatch the needs to be adjusted (moved back a hair), would the upper and lower latch still "jive" or would they appear "out of line" and the male upper would not go into the female lower.

 

The rubber buffers do adjust - they screw in and out.
Make sure they are all the way in.

 

In the headliner there are 2 small pull out covers at the hatch hing points. If the hatch has slid downhill ( to-wards bumper) then your male catch is too far back to latch to the female receiver properly. What my son and I did was loosen the 4 bolts ( hex nuts) under headliner and manhandled the hatch forward as far as we could. It takes 2 people. ( it won't go far) then re-tightened the bolts. When the bolts were out I elongated the holes in the liner with a screwdriver before reinstalling bolts for a little more movement..all you probably need is a small fraction of an inch and in my case all was well...in fact very well.

 

The Sharks in Hell method

 

Thanks for all the response, but still not there yet:

1. Rubber adjust blocks are off.
2. Rubber buffers are all the way in, then off just for grins.
3. Drive arm is at highest and Cam is not engaged (lowered) and pushing on the tongue)

I had a helper lay in the hatch while closing lid and he said rubber buffer not the issue. Male latch is going into female latch, the plastic lock on the top hatch is going into the female and it is engaging, but not going deep enough into the female to release and lock.

So I am stumped here. My next thought is to shim the lower latch with some metal washers to raise it and see if that helps.

Any other thoughts?

 

loosen the top part (the male end) and fit 2 pieces of nylon zip tie on the front and rear edges of the fitting then retighten the screws

 

Shawn,

If the new hatch lock mechanism is installed correctly you should be able to close the hatch without slamming, the key unlock and the cam unlock mechanism should work correctly, the hatch should be correclty in line with the gaps between the body and the hatch even on all sides and the hatch should not make any rattling or squeeking noises nor come unlatched when driving.

The following is a systematic method of installing a new latching mechanism or adjusting a old one and it can be undertaken without assistance.

When adjusting the closed position of the hatch, the bumpers should be fully screwed in initially and the side guides should be released or removed.

To save excessive work in adjusting the latching mechanism by opening and closing the hatch I recommend that the initial work be undertaken with the hatch fully opened.

The latching mechanism should be tested for fit with the receiver (female) mechanism removed from the body of the car and hand latched to the male mechanism by pushing it onto the upper mechanism by hand.

This procedure allows the electric operated cam to be held out of the way by the pushrod, so that it does on have any influence on the key operated latching mechanism whilst you check its correct operation and latching to the female mechanism.

If it is too hard to get it the key operated mechanism to latch there are 2 possible reasons reasons,
1. the new rubber insert is too big or if it is an old shimmed out insert is used, the shim could be too thick, and
2. the the key operated nylon latch is too worn or it fulcrum pin is worn causing the nylon latch not to fully catch under the receivers fixed latch receiver.

As you are using a new upper and lower hatch locking mechanism all should be OK, but as previously advised by Roger in another post not all new parts function correctly. By undertaking this procedure you can check all the key latching mechanism as well at the correct fit of rubber insert and its clearance.

If the female section of the latch is too snug on the male section you may have to remove some of the ribs thichness off the aft section of the insert, so that you get the correct insertion depth for the correct latching.

If this hand testing key operation is OK, as it should be with the new upper and lower hatch mechanisms, you can now test the cam operation release by hand by pulling down on the push rod to get the cam to release the nylon latch.

If the cam does not push the the latch sufficient to release then you have a problem with the new items.

One fix for this has been described to get a greater arc of influence by the cam is by fitting a couple of nylon ties around the cam. Once you have the female part latching and unlatching correctly you can now again test the key operated unlocking mechanism thereby ensuring that the both unlocking system work satisfactorily, and they are not too stiff and the lower female receiver should "pop off" the upper tongue into you hand. When you release the latch by key or cam be sure you catch the receiver as it will really "pop" off the male section due to the spring loaded nylon piston in the receiver.

If the key is too stiff then more silicone spray lubrication maybe required onto and around the key mechanism. If it still does not "pop off" the male section I have found that sometimes the rubber insert can jam the lower receiver's nylon spring loaded piston release mechanism.

If this is the case then some "relief" maybe need to be made at the bottom of the aft inner section of the rubber insert to give clearance.

By undertaking these tests, by hand, you individually test each system and can really see and feel whether the total system is operating as designed, with out the PITA of shutting and opening the hatch lid and working blind.

Now fit the lower receiver into the car without any shims under the flange. I would suggest just nippin up the 4 allen headed set bolts, so that there is a small amount of friction present, which allows the male and female sections to self align when the hatch is closed and remain in their alligned position.

Now open the hatch using the key and tighten the set bolts. When fitting the female mechanism to the body it is imperative that no aft pressure is applied to the upper male mechanism via the lower mechanism being too far in the aft position, otherwise you could crack the sides of the tongue of the male mechanism. All the pressure on the male section should be applied by the ribbed aft section of the female receptical.

One suggested fix for assisting the unlocking cam alignment is to a shim under the after side of the flange of the male tongue to bring the nylon unlocking piece more under the arc of influence of the electrical operated unlocking cam. This fix will work initially however, there will be too much aft force applied to the male mechanism with the result of cracking the sides sections. I have developed a repair for these cracks, but it is still under test in my car.

You can now test the latching of the hatch in situ to see whether it catches without the need to slam the hatch closed. If it closes correctly and can be opened by the key easily it should "pop up" a few millimetres under pressure of the receiver spring. If it does not "pot up"then the receiver's spring loaded nylon piece may be jamming and need some lubrication or added clearance.

When the hatch is locking and unlocking correctly, you can now adjust the bumpers to set the hatch edges to align with the body to get an even gap between the hatch and the trunk body. Adjustment should be by small increments otherwise you may jam the key operated latch into the lock position, as the force to close the hatch increase the more you adjust the bumpers. This adjustment is a trade off in alignment and closing force required.

If the gap is too small between the after edge of the hatch and the body after adjustment of the bumper, then full width shims can be added under the flange of the female receptical to get the gap acceptable. If shimming is undertaken then you will have to readjust the bumpers.

When you are happy with the closing force, alignment and the pressure require to turn the key to open the hatch, you then adjust the position of the motor operated opening cam as per the WSM. When operated by the pull switches it should "pop" the hatch up a few millimetres (as previously described) and when the switch is release the electric motor should continue to operate to park it in the correct position.

If the hatch does not "pop" the hatch after all of the above then the alignment of the two hatch locking mechanisms is slightly out and should be again re-aligned again as described above by just pinching up the set bolts, closing the hatch and then opening the hatch and fully torquing up the set bolts.

When all of the aboce is working correctly you can now adjust the two side guides to ensure the hatch does on move from side to side when the car is driven.

Now you should now have a fully operating hatch locking and unlocking system as designed.

Tails 1990 928 S4 Auto

 

Thanks Tails, wish I had that info before wrestling with this mothur!!!!

I will get to work on that and see what how it turns out.

This morning I tried using a few metal washers as shims on the front part of the female latch (closest to the inside of the car).
This basically raised the front higher then the rear of the female latch, with a little pressure I can get the hatch to latch (at least I can run to store without worrying about it popping up on me).

Not the fix I am looking for...............but will dig back in this week.

So what this tells me is that the actual hatch has slid "downhill" as mentioned in a previous reply, so that when I raise the front of the female latch enough to counter the hatch moving "downhill", that is when I get it to latch.

Does that make any sense?

I agree I need to still remove both parts and make sure they are working without being installed into the car.

But at this point I am leaning towards the actual hatch being out of adjustment.

Agreed though, I have to remove the parts and ensure the are working properly prior to install.

I am beginning to hate hatchbacks!!!!

 

Hi Shawn,
I have noticed that these hatches over time do tend to slide down hill. What I do is have the hatch open. All four bolts loose. One guy with a large regular screw driver push JUST the latch from the rear towards the front...not really pushing the whole hatch. This will move the latch forward and taking the hatch with it. I tried pushing the hatch but all that does is pivot the hinge. The screw driver ( or anything else that will fit under the open hatch ) will move just the part you need to move. Attached is a pic of the access points. They just pop out. No need to remove headliner