Had a broken door cable?

Daryl Adams · 04-23-08, 12:50 PM

So it's the first warm spring day after an especially crappy winter and I'm excited about driving the GT40 to work. I've been waiting for this day for three years. I get into the car, start her up, go to get out to close the barn door and the driver's side door cable breaks. The latch refused to work with what's left of the cable, so I had to clamber out the passenger side. MAJOR disappointment. Anyone been here? Any shortcuts to gaining access to the latch internals? Thanks.

Jack · 04-23-08, 01:11 PM

While in Monterey last year I took pictures of #1083 door latches, I think I can make them and will do away the cable. Its pretty easy to get to, just take all the screws out from the door panel and its just to the left. I will send you pictures when I get home tonight of the ones on #83.

Mike Drew · 04-24-08, 02:26 AM

I just can't believe that Superformance did such a great job replicating the GT40, but then took such a dumb shortcut and replaced the proper GT40 interior doorhandles (which are purely mechanical, as seen here on #1080),

with a stupid pull cable which is not only not authentic, but is just begging to fail.

I'm still years away from getting my own Superformance, and I would hope that they would ditch the shortcut and install proper, original-style hardware. If not, mine will be modified appropriately before I ever get inside it.

And FWIW, the only Superformance car I ever sat in, a brand new rolling chassis at the SPF HQ in Irvine, came completely with a broken door cable; the salesman had to let me out of the car....

Jack · 04-24-08, 07:46 AM

Thats it Mike! You can drive mine dude, we just got to be in the same place at the same time.

chuck smith · 04-24-08, 11:02 AM

I was under the impression that some 40s had pull cable latches. I actually like the pull cable better as far a ease of use, compared to my CAV which has the above type latch. The SPF system should certainly be more stout however, it is too fragile. I bet Dennis Olthoff can fix that.

Daryl Adams · 04-24-08, 12:05 PM

Quote:

Originally Posted by chuck 1

I was under the impression that some 40s had pull cable latches. I actually like the pull cable better as far a ease of use, compared to my CAV which has the above type latch. The SPF system should certainly be more stout however, it is too fragile. I bet Dennis Olthoff can fix that.

Okay, here's the deal. I pulled things apart last night for a look. There was just enough slack in the wiring harness to pull the inner door panel out far enough to see the latch assembly. Bottom line is that my latch shaft was not rotating, even after being released by the cable. Sooo... the first reaction is to pull a bit harder on the cable, which overstressed the connector at the cockpit end, and it failed. The return spring seems fine, and exerts plenty of return tension. There doesn't seem to be any physical restriction on the latch shaft, so I'm hopefull that simply lubricating the thing will solve the problem. My rolling chassis sat in Dennis Olthoff's shop for nearly a year waiting for the drive train, so that may have contributed to this. There is no evidence of any factory applied grease or other other lube. Aside from that, I think the cable attachment point is too near the centerline of the shaft. If the cable were attached farther out, perhaps at the same point as the door handle rod, there would be a much more favorable lever arm. There might be a bit more cable travel required, but the tension on the cable would be substantially reduced. We'll see what happens after I oil things up. As for the cable versus lever question, I have a photo of Jochen Rindt driving a GT40 with a cable operated door, so I guess it's certainly authentic. It's a moot point, though, if the latch shaft won't rotate.

Daryl Adams · 04-25-08, 10:10 AM

Oiled it up last night and got it working just fine. Just need to repair the cable. Thanks guys.

SpyderMike · 04-25-08, 11:44 AM

any pics of the inside of the door Daryl?

DaveM · 04-25-08, 12:36 PM

Some interior door pics here
SPF GT40 Power Door Locks - David Miller

Daryl Adams · 04-25-08, 02:55 PM

The latch photo is actually rotated. The correct orientation is below. You can see how close to the pivot the cable attaches. This is the passenger side latch, driver side being identical but opposite hand. The door handle rod and the release cable are attached to the lever arm of the release pawl. When pulled, they rotate the pawl away from the notched disc of the latch shaft, freeing the torsion spring on the latch shaft to rotate the latch to the open position. It was that torsion spring that was hanging up on mine.

SpyderMike · 04-25-08, 04:53 PM

I see - thanks!