85 300D rear door stuck iopen in 2nd detent
 

The passenger rear door on my rust free 85 300D was feeling kind of stiff while opening and closing it last week. That door does not get used much. I was opening it part way (1st detent). Yesterday, I opened it all the way (2nd detent) so I can get better pics of the pristine floor pan to put it up for sale. When I was done, I could not close the door! It was stuck in the 2nd detent position with door wide open. I took the door card off and sprayed it with penetrating fluid which didn't help. Took the door strap out and found one of the balls came off and the strap bent (probably from me trying to force the door close).

Circled in red is the dislodged ball bearing, you can see the strap is bent compared to the 4 spares that I have.

Are the 2 on top a different style for the rears? Which type is better?

The strap in my 85 probably was never lubed since it was built in the factory, together with the rear door's lack of use, probably contributed to the ball bearing coming off.

Looks to me the only way to properly lube it is to take the door card off, reach in and smear it with grease, or take the strap out to clean and lube in order to do the best job possible.

I still have to clean up a spare and install it.

https://photos.google.com/photo/AF1Q...TxG1OR_XzSnKSk

Has this happened to anyone here?

The pic of the failed door strap is in the 1st detent position. This is because I did not give a full description the the full sequence of events. I actually cleaned and lubed it, reinstalled it and was able to close the door with a lot of force, but it was still stuck open. The second time I took the strap out, I found the loose ball bearing.

Yes, I have had a rear door check on my 300D fail and could not close the door. I also found it useful to lube the door hinges using a device used to lube chain saw chains. It comes with a pointed nozzle that fits perfectly into the lube point in the door hinge. If you need a good used rear door check just PM me. Thanks.

I replaced the door check strap on my 300SD a few years back. It was pretty easy and not very expensive. Rear driver's side.

Cleaned my 2 spares with solvent, tooth brush, and abrasion with terry cloth soaked in solvent + needle nose pliers, which really helped in removing the hard/ dried up grease/ grime. The one on the left has been greased, the other one waiting to be greased. Both are tight with no play. Installed one, door action is now super smooth, detents hold the door positions extremely well.

Been there, done that... twice.

You're lucky that you were at least in a place where you could take the door card off and play with it. Try having the door stuck open deep in the hood, at night! After that episode, i cleaned my spare and goo'ed a buncha Redline grease in there.

The OEM ones look like a pretty stout assembly. Springs are uber stiff, tolerances tight, metal is pretty beefy. I think the grease just dries out over the many, many years and somehow seizes the ball/spring assembly. Kinda find it hard to believe that the assembly just gets stuck in place. I bet lack of lube causes the ball to come detached or free of the spring, then jams up the entire mechanism

NO FUN
 

Been there, done that, as mentioned I was 'In The 'Hood' so leaving the driver's door open wasn't going to work.....

The factory tool kit is sufficient to remove the door card and the door check .

I find sometimes the ball bearings are worn and no longer perfectly round, this guarantees they'll jam up again, when you take it apart but sure to have it wrapped in a rag as those ball bearings go ! POING ! and you'll never see them again .

Long fiber lithium grease is the ticket here .

It must happen to others as some previous owner replaced the ones on the front door and I remember one of the Rear door being hard to move.

I stuck the skinny tube of the WD-40 and sprayed inside and that freeded it up.

I am assuming the original issue was rust because the bottom of the doors in the front is rusted out and to a lesser extent the same with the rear doors.

I think it is more an issue of lubrication. I have a pristine 1985 300D with absolutely no rust and had the same rear door check issue. Fortunately I have several good used door checks so was able to fix the issue easily. Also, I found the proper grease gun (used to lube chain saw chains) to lubricate my door hinges. That helped considerably.

No plans to take it apart and reassemble since the arm is bent and I still have another good spare.

Working with springs is dangerous, one must be careful with eye/ face protection. I know a friend's brother (mechanic) while taking apart a power window years ago, a spring let go and hit one eye, result in total vision loss. What a shame!

Agree it's lack of lube and lack of use of the rear doors. Not sure what a chain saw grease gun looks like. From studying the strap, looks like Lithium grease spray can with a bent straw can be inserted into strap arm opening in door to squirt grease into the 2nd detents (with door in 1st detent position). Make sure the window is up or risk Lithium grease all over the glass.

I've never had good luck repairing with lube 1 that got stuck. They seem to stick again in short order. I can't explain why. I scalp them from the yards along with the part that trips the door latch and the mono valve. Still, I'm low on all 3. Could also use the cabin temp display because all of mine are black.

Door Checks & Hinge Lube Tool
 

The reason just spraying in new grease doesn't last is : there's DIRT in there that needs to be cleaned out before re lubricating .

I've seen quite a few where the ball bearing cracks in half ~ I can only imagine the forces necessary to do that .

? Anyone got a link to this chain saw lube tool ? .

I'm pretty sure it's a needle typ adaper that snaps on the end of your regular grease gun, I saw one a while ago and have been trying to find ever since, please help .

TIA,

OBTW : a VW mechanic who didn't understand the newfangled 1971 Super Beetle's McPherson struts, undid the top nuts on one and when it let go it went in his stomach and out his shoulders, splattering his spine all over the shop wall .

RESPECT SPRINGS ! ,

I tried this today: with the rear door open in the 1st detent position, you can stick your finger in there and feel the upper and lower detents. Grease can be applied with fingertips, no special grease gun needed!