C2 French Locks and 1 Tab ?

[Alan Drake]

Did I read in some document, like the AIM, that only 1 tab of the exhaust manifold french lock was bent over. Such makes sense, since to bend 2 takes more time not to mention would not line up that well.
Does anyone know where a written ref can be had.
Alan

[Dave M.]

Re: C2 French Locks and 1 Tab ?

Hi Alan, I couldn't find any reference in the AIM. I didn't think there would be any. The manifolds were installed on the BB engine at Tonawanda. I checked my original '67 435 car and only 1 tab at each end of french lock was bent over the bolt head. There is also a thick spacer washer used at each end of the lock, placed against the manifold before lock is installed and tab is then bent over bolt head.

manifold,
spacer,
french lock,
bolt-w/1 tab bent

Hope this helps
dm

[Alan Drake]

Re: C2 French Locks

That's what I would expect, however the judges (C2) at the National where looking for two to be bent over at each stud. Now in my case I forgot to bend any over, so regardless of what is correct I lost. Still I remenber reading it some place.
Alan

[Douglas L.]

Re: C2 French Locks

Allan,

For what it's worth, I have an very original 390 horse car. One tab bent per bolt!

[Allan J. Wicklund]

Re: C2 French Locks

My recollection from years ago is that the angle for bending point is at different degree to suit a good mating of just one Tab. Al W.

[Joe L.]

Re: C2 French Locks

Allan------

That's just how it is.

[Alan Drake]

Re: We Agree, but the judges do not!

Looks like we all say only one is bent over at each bolt - which makes sense.
However the judges (for 63/64) are looking for two not one. Must be some writings someplace to offer as proof, but where?

[John H.]

Re: We Agree, but the judges do not!

That's just flat wrong - the tabs on the lock are spaced/designed as they are so ONE of them will always line up more-or-less with a flat on the hex head of the bolt. If both tabs were intended to mate with flats on the bolt head, you'd have to manually re-orient the bolt head (after torquing it) so two flats aligned with two tabs, and that isn't going to happen, as the tabs aren't 60* apart.

[William C.]

Re: We Agree, but the judges do not!

At least all the mech judges I have worked with were very much expecting one tab to be bent.

[William C.]

Re: We Agree, but the judges do not!

Look in the radio section of the aim as some of the bolts must be removed to install the brqackets for the radio shielding. I'm not home yet to check, but that is the first place I would look for "Proof"

[John D.]

Re: C2 French Locks and 1 Tab ?

Alan, One tab bent is typically the norm. Never saw two bent on original cars. My restored 63 just has one bent tab. Can't imagine an assembly line trying to bend two over when the parts are on the conveyor. That would be interesting and quite impossible wouldn't u think.You don't find this kind of stuff actually written unless it's some kind of work order. Probably buried in the aims. NO actually the AIms won't be much help??? Look on U65 Sheet 9.00 C357 or 325. SHows the exploded view of the locks but not the installed one. Maybe it's somewhere else but too hard to find. John

[Allan J. Wicklund]

Re: C2 French Locks

Thanks Joe! I've never been a "Have your car Judged" type of guy. I'm just an ole Dinosaur with some old time practicle knowledge! It is fun though to think about some of todays experts knowing they weren't even a Gleam in the old man's eye when we were tearing the streets up in these cars! LOL Al W.

[Peter L.]

Re: C2 French Locks and 1 Tab ?

We'll get those production line folks to see it our way sooner or later.

[John D.]

Re: C2 French Locks and 1 Tab ?

Peter,We sure have a lot of repeat posts over the years. I have personally tried to use the archives and have been successful once in a while. But with so much BS on here (me 2) it's hard to find stuff. Remember not long ago someone asked why do you call them French locks.? That was good for about 50 posts alone.

Just remembered Peter. We were talking about the 63 rear axle French locks or the lack of them. Trying to say we were discussing whether or not the 63's had french locks on the half shaft ends, etc. JD

[John H.]

Re: C2 French Locks and 1 Tab ?

As a matter of fact, there was an arrangement between St. Louis and Flint V-8 whereby Flint left the exhaust manifold bolt lock tabs open (not bent over) on all Corvette-suffixed engines, to simplify removal of the bolts at St. Louis in order to install the horizontal ignition shield brackets (it was a PITA to pry the tabs open to get a socket on the bolts to remove them). Flint V-8 had no clue whether any engine was going to wind up in a Corvette with a radio, so they just left all the Corvette lock tabs open, and St. Louis bent them all, whether the car got a radio or not.