The Lotus Grand Tourers

Thoughts on this, before I resort to spending more money, please ?

Driver's door - locks & unlocks OK from outside and triggers central locking some of the time to lock but very very rarely (if at all) to unlock.
Passenger door - locks & unlocks from outside and triggers central locking although occasionally the system "hunts".
Driver's door - very hard to lock or unlock from inside using the "lock" handle. There's considerable resistance to movement although it does occasionally work.
Passenger door - no problems at all locking and unlocking from inside using the lock handle.

All rods in the driver's door have been tweaked and lubricated and the lever that joins the CL actuator to the rest of the system is pivoting correctly. With the driver's door actuator connecting rod disconnected, CL is perfectly happy.

I think there's a fault somewhere inside the driver's door latch (changed about 100k miles ago), on the section that handles the interior mechanism, but I'd welcome opinions.

(And if I'm right - does anyone have a spare they'd part with?)

This may not be that helpful but I have a similar problem sometimes which I think is caused by the door catch not full engaging in the lock due to the door being slightly out of line. Try getting someone to lean on the door with you inside and see if it helps. Just a thought.

Only locks from inside if latch locates on striker,the latch on mine was very worn at 128k miles and would not shut because of this without several attempts to get central locking to activate,replacement latch solved this but a nightmare job,manufacturer out of business and not easy to get good replacements especially for drivers side,PNM were refurbishing them

Grant wrote:This may not be that helpful but I have a similar problem sometimes which I think is caused by the door catch not full engaging in the lock due to the door being slightly out of line. Try getting someone to lean on the door with you inside and see if it helps. Just a thought.

It was working perfectly until quite recently. My door beams are still sound (inspected when the window frames were done, and again this weekend when I had to take a frame out to replace drop glass) and correctly aligned.

I see you have tweaked the rods, but I can tell you that one rotation of any rod can make a big difference. I spent countless hours before and after replacing my door beams to get my locks working right...
When you adjust the CL, it affects the inside mechanism, adjust the key cylinder and it affects the CL - which again affects the inside latch. I've also noticed that the rods can drag on the door card where the mechanism attaches. I put a minor bend on one rod to alleviate this - in hind sight I probably should have shaved the fiberglass back.
There are soooooo many adjustments that impact other adjustments it's nuts. Then when you start putting the door together stuff stops working because the door card adds pressure!!!! (The door card on my Excel has the indent to accommodate the CL motor, well that indent causes the window reg to bump it and then when I add the door latch cover it the puts a resistance on the inside door lock tab and potentially the rod which makes the CL work harder (or it can't work hard enough) to actuate the locks. It's such a PITA to get balanced. I've had it work card removed then fail when it's all back together.

**Starting point** I've noted that the latch mechanism wears out and the key latch interlock doesn't play nice (door locked, outside door paddle doesn't move freely). Honestly, I've found the key latch rods are the easiest to adjust and tweaking them can clean up the interlock at the mechanism which then makes the inside door latch and CL work better. SO, I'd start with the key cylinder rods give it a spin or two and see what improves. These are the easiest to manipulate IMO and have the biggest impact since they are short and move the greatest distance.
MY locks are now 98%. CL works, though I have to tug my Pass side exterior handle 2-3 times before it opens from the outside. Inside no issues. Using the key has no issue, just CL unlock on pass outside is touch n go.

I adjusted my CL by placing them in the bin about 15 years ago. Might seem a bit radical but have you tried the lock mech by disconnecting CL rods to see if its a cure. ( yes I have been on the stating the obvious course ).

Bash

bash wrote:I adjusted my CL by placing them in the bin about 15 years ago. Might seem a bit radical but have you tried the lock mech by disconnecting CL rods to see if its a cure. ( yes I have been on the stating the obvious course ).

Bash

Yes, and it isn't.

My driver door latch would not shut fully from inside but would from outside. I have no Central locking (1985 car non SE).
I opened up the latch mechanism by drilling the head of the side plate rivet/bolt, this was worn inside giving play in the latch. I replaced with a new bolt and used two nuts to secure again to the side plate. The outside nut does not foul the door to pillar gap.
It works, the job was done more than 12 months ago.

Dave the cog.

Thanks Dave. It's good to know it can be repaired.

I'm also wondering if my latch might have flexed a bit when we did the window frames. Looking at the diagrams, it should have a spacer plate and some washers between the latch and the beam (late model). I know the plate is there, but I don't remember refitting the washers...

Did you have any spare parts laying around?!? LoL.
They are pretty hearty sized aluminum? washers about 1/4" thick; they are a bit tedious to get placed as the bolts need to go through them but they float around behind the latch during install - I used a smaller gauge alan/hex wrench to index them before getting the bolts on. I'd think you'd remember fiddling with them. But I could see them causing a minor issue if they weren't in place. pretty easy to check.

Sussed it. The latch is fine - but the rods were fouling on the window frame.

For historical reasons, my frame isn't bolted to the door beam at the bottom of the rear edge (thanks to someone who replaced the beams for me and forgot to mention that they sheared the bolt in that mounting point...). As a result, it was standing proud of the beam by a few mm and just catching the rods and the levers on the latch.

After a bit of fettling, it's all working properly again.

Side note - don't bother twiddling the rod from the actuator to the lever that connects it to the interior handle rod. It won't alter the length. The rods are held into the fixings on the lever by grub screws.

Glad you got it sorted. I have found adjusting that grub (I call it a set screw) on the actuator does have an impact on the leverage the CL can exert on the lock mechanism, but if not in the sweet spot just does very little to improve performance. Chances are it's in the best place already, unless the screw loosened and the rod came out of adjustment.