Need some help.....

[Rocfrog]

My neighbor has a '71 ( I think ) pickup that is having some big time passenger side door issues. The original latch doesn't seem to stay locked at all. So he picked up a new latch from LMC thinking that was the problem but when we put in the new latch and it locks it is next to impossible to unlock, and all this testing is with the door open or closed.

Not really sure what to do.....I'm kind of baffled.....

Nick

[SS Tim]

Might want to clarify this a bit. Does the door latch close and latch properly? Does the door unlatch properly with inside and outside controls? Does the latched door lock and unlock properly?
Sorry, but having been both a tech. and a service writer I have seen all to often "Yes that is what the repair order says but that is not what I meant".

[68gmsee]

Originally Posted by Rocfrog

My neighbor has a '71 ( I think ) pickup that is having some big time passenger side door issues. The original latch doesn't seem to stay locked at all. So he picked up a new latch from LMC thinking that was the problem but when we put in the new latch and it locks it is next to impossible to unlock, and all this testing is with the door open or closed.

Not really sure what to do.....I'm kind of baffled.....

Nick

Hard to determine what part you are referring to. Can you send the page and reference number of the latch from the LMC catalog?

You can also do a comparison with the other side to see if you notice a difference but in either case, he may have to call LMC. There's been several instances of parts being bought that are not up to par. It may be that they are unaware and we need to let them know so they can make corrections.

[So.Cal.Super]

Did He replace the door seal lately?

[Rocfrog]

Sorry guys it was late last night and I really didn't know how to describe what is going on.....

Originally Posted by SS Tim

Might want to clarify this a bit. Does the door latch close and latch properly? Does the door unlatch properly with inside and outside controls? Does the latched door lock and unlock properly?
Sorry, but having been both a tech. and a service writer I have seen all to often "Yes that is what the repair order says but that is not what I meant".

The door works properly, as in closes and opens and with the old latch assembly it will lock and unlock just fine, but when you go to "check" (Open the door) to see if it's locked the door/latch just pops unlocked no matter what. When we put in the new door latch assembly from LMC the door once again works properly in the opening and closing but now when you lock the door it is stuck in the locked position and if we try with the key it is going to break off in the door and when you try and pull up on the lock plunger it takes almost lifting the truck to get it to unlock. Now with the new latch unit out side of the truck it works as it should with good solid movement and nothing binding but once it's in the truck and in the lock position is where the trouble is.

Originally Posted by 68gmsee

Hard to determine what part you are referring to. Can you send the page and reference number of the latch from the LMC catalog?

You can also do a comparison with the other side to see if you notice a difference but in either case, he may have to call LMC. There's been several instances of parts being bought that are not up to par. It may be that they are unaware and we need to let them know so they can make corrections.

on that page it is in the upper photo #10. This is the second assembly he got from LMC the first one did the same thing.

Originally Posted by So.Cal.Super

Did He replace the door seal lately?

Not that I'm aware of....???


Nick

[Rocfrog]

anyone....

Nick

[SS Tim]

Sorry Nick,
Thinking on it. But at least now I konw what the problem is. The latching is latching its just the lock function is binding installed. Need to play with a door a bit and I'll get back to you. At this point it sounds like either the lach is being preloaded by the door shell during installation or an assembly problem. Have you compared the installation it to the other side?

[Rocfrog]

No worries, I was just trying to keep it at the top to give others a go at it as well.

We did not compare it to the other side, but the new latch is installed exactly as the old one was removed. He's pretty much got it down to a science at this point. LOL!!

Nick

[Rocfrog]

TTT....

Nick

[SS Tim]

Nick,
Trying to work the problem and everything is really pretty clear in the manual. First off try to lock the door with the door open but latched, you will have to manually roll the latch to the fully closed (latched) position. If it still dosen't lock properly then the latch might be preloaded to unlatch. This is probably by the outside door push button plunger. You could test my theory by trying to lock the drivers door while holding inward pressure and some travel on the button. The thought here is that the flap on the latch that the push button contacts is not in the same relative location as the stock latch was. The other thing you could do is remove the outside handle assembly (two screws) and try it again. Hope this helps. I am out of ideas and the service manual is pretty light on info beyond striker shimming. The doors I had hoped to play with have frozen latches at this point, sorry.

[Rocfrog]

Ok not sure I'm following you 100%.....

The problem we are having is with both the original latch and the aftermarket new one...

On the original latch no matter what we do it never actually locks. you can close the door and lock it but when you push the button on the outside door handle to open it, it pops the lock up and unlocks it....

On the new aftermarket latch once you lock it (either with the door opened or closed) it pretty much stays locked.....

not sure what your meaning by " lock the door with the door open but latched".....are you meaning to make sure the "lock" lever is in one of the grooves/valleys of the cylinder on the latch??

Nick

[Rocfrog]

Still having issues with this door.....

hoping to find an original latch maybe that might help.....

Nick

[LockDoc]

-
With the window rolled down you can shine a light down inside the door and see the door latch and lock to see what they are doing. On the old latch I would say that the lock mechanisim is not engaging all the way and that is the reason the button pops up when you open it with the outside door handle. Did you try the old latch with the inside lock button removed? If the button is screwed down too far it will keep the lock mechanisim from engaging all the way and cause the problem you were seeing. Also, if you have the lock cylinder installed wrong it can cause the same problem. I posted a picture of the latch and lock cylinder here...

http://67-72chevytrucks.com/vboard/s...d.php?t=425488

Also read this thread.. Just in case.

http://67-72chevytrucks.com/vboard/s...d.php?t=530099

I would spray the crap out of the old latch with penetrating oil (not WD-40) and put it back in and try it again.

I don't know anything about the new latches, I've never seen one.

LockDoc

[silver fox]

i have a 69 c20 long bed, that has that same problem
i have to push on the door as i'm turning the key to lock the door

[Rocfrog]

When the door is locked the inside lock button is no where near in contact with the door it doesn't even seem to go down all the way, but at the same time it goes down to the same place with the new replacement latch and it is fully locked.....

What baffles me the most is that with between the original and the replacement we are having issues but we are having two completely different problems. So this leads me to believe that there is something in the door that is affecting the latches.....but looking in side as they are both installed I see nothing in the way....

Nick

[LockDoc]

-
OK, have you tried moving the striker plate out on the door jamb?

I would try moving the striker plate on the door jamb out a little. Just be sure to mark around it with a fine felt tip marker before you loosen the bolts so you know where it was originally. I would only move it out about 1/16th of an inch to start with. Make sure it doesn't drop down any.... Then close it and try the lock again.

LockDoc

[Rocfrog]

We messed with the adjustment of the striker plate at first to try and fix it before the new latch and it made no difference, I'm trying to get him to take some photo's of the inside of the door/latch so I can provide some visual references....

Nick