INTERMITTENT/NOT WORKING DOOR CATCHES

[Chunky020]

I am having trouble with both door catches!, driver side is intermittent to release and the passenger side wont open at all unless you thump the inside until the latch lets go!or you drive the car and it opens part way!, I have had a play with the drivers side this afternoon and adjusted the bolt from the push button so it now in contact with the lever( made no difference to how the latch operates)so still not working correctly,the pin seems to flip over ok!.when the door is open should the latching pin be at the top or bottom when closing the door?.
looking at new B post striker plates I have noticed that new ones have a straight internal vertical edge, mine are hooked out at the top of the catch(is this what is holding up the pin?

any tips appreciated

[Nick Jones]

They are not the greatest of devices, though to be fair they are now very old.  Lubrication is good, especially the spring loaded wedge at the bottom of the striker plate.

The release problem is most likely that the internal handle spindle mounting plate has come loose and moved backwards on the door shell, effectively making the rod too short to fully disengage the catch.  Mine does this periodically.

Nick

[Chunky020]

Thanks Nick

will give that a try

Robbie

[Stu 1986]

Also check there isn't any paint on either the catch mechanism or the striker. They're meant to be bare metal not painted.

[Chunky020]

thanks Stu,

but all clean and no paint on them !, I might try a new B post striker plate as the drivers side is hooked out on the back edge where the pin drops (pin could be getting hung up there ?,

[scotty71]

had the same problem with my doors, so i brought new striker plates. and lubed the locks up, as they would bump open by 1/2". new door hinges helped as well.
you will find the profile on the striker plates, will needed to be filed on the top edge a bit. his will stop the door jamming when it is about to shut on the striker plate. taking some pictures, but the are to big to post here.

scotty

[RobPearce]

Tessa has similar problems with the driver's door in particular. Sometimes closes well but other times gives the impression of being closed but then flies open as I pull out of the drive. When opening, sometimes fine, sometimes remains apparently latched, normally releasable by pulling it fully closed (which isn't easy with the window up). I shall try some of these suggestions on it...

[scotty71]

this is what i had to do, to make them close better. i found the filing the striker plate top edge helped. this allows the door plate to shut tighter together when the door is closed.

[Antonnick]

I have been searching the forum for this informations. I see it was a few years ago - I have borrowed the image above inorder to explain my problem. When I close the right hand door , it does not lock. the door is flush and I have tried to adjust the striker plate with only limited results .i.e sometimes the door stays shut, sometimes it flies open.

I am trying to work out what should happen when the door is closed. REfering to the copied picture . Is it correct, that when closing the door, the catch rod on the door mechanism ( horizontal arrow) strikes the striker plate and thengoes downwards ( vertical arrow)?  The spring on the door catch mechanism seems to be intended to pull in both directions. i.e catch up and down.

Edited April 1, 2022 by Antonnick

[Rosbif]

I recently had a problem that sounds similar to yours. The drivers door would give the impression of being closed properly but would occasionally fly open on the first left hand bend. If, when I got in the car, I moved the inner door handle to the locked position it did seem to prevent the problem, but not a proper cure.

I lubricated all the mechanism and removed the door car to clean and lubricate the whole of the operating mechanism. There was old dried up grease and dirt. Since doing that, only a couple of weeks ago, I haven't had the problem, need to go around a few more bends at speed to be totally sure 😁.

Hope this is of some help to you.

[RobPearce]

The pin on the door mechanism "rests" in the middle position. The bottom position is fully closed, and sits at the bottom of the cut-out, where the down-arrow points in your photo. The top position puts it at the top, where it can't quite open because the striker plate has a lip. The pin only goes that high when you are pressing the release button, to help push the door open just a fraction.

Note the wedge underneath the striker. That is spring loaded and must be free to slide. It tensions up the vertical position. Also, note that the top edge of the striker is very important. It controls the position of the latch pin relative to that cut-out. If the door is able to drop, because the top of the striker is worn, then it can push the pin upwards towards the release position.

[Antonnick]

Thankyou RobPearce, that is what I needed to know. Now I must work out how to achieve it. 😐

I think the problem is enhanced by the loose "latch pin" as you call it. I discovered after removing the lock mechanism to clean it that the inside splayed rivet was broken in several places allowing the pin to wobble about a lot. So I drilled and tapped 3mm and placed a large washer ( not seen in the pic as this was the second attempt) and bolted this up. It seems to have worked and the pin is a lot stiffer.  

Also there is no wedge any more on this side - I will try and make one using the left side one as a template. 

Fortunately I have got hold of new hinges with no play in them at all. Heavy snowfall today, so will try in the next days.

[1147cc]

OMG  I hate these...

Had the same prob on a car.  and one of doors had the large round spring broken on the end, so look for that too.  it seems so strange to me that the latch bit is designed to hit the back of the catch and kinda bounce down to the latched position.

IF I had know how bad these were I would have welded in some Spitfire mechs before doing the paint.