1974 Rear Halfshaft Flange French Locks

[Paul L.]

My 1974 rear halfshaft flange bolts are not secured by french locks, either left or right side. I just noticed that fact this week. This has never presented any problems. The car is an L-48. Are those locks just for the L-82 and LS-4 more powerful engines? (The various catalogues do not say.) Or should I add them for extra fastening security?

[Jack H.]

Re: 1974 Rear Halfshaft Flange French Locks

The current Judging Guide makes no distinction on the use of French locks based on engine configuration.

Often, the factory originals were discarded by prior owners/mechanics in favor of a different or 'better' bolt securing system, eg. dipping the bolts with a 'glue' like Lock-Tite...

[Paul L.]

Re: 1974 Rear Halfshaft Flange French Locks

I suspect that blue LocTite was used. And it seems adequate.

[Joe L.]

Re: 1974 Rear Halfshaft Flange French Locks

I suspect that blue LocTite was used. And it seems adequate.

Paul------


ALL 63-79 Corvette applications, except, POSSIBLY, very early 1963, used the french locks on the half shaft flange bolts.

The original french locks are made of a "special steel" that's guaranteed to rust almost instantly. I use only stainless steel french locks. That way, they appear like new forever. Caution: these will not "survive" a "magnet test".

[Paul L.]

Re: 1974 Rear Halfshaft Flange French Locks

Joe,
Are those the $7.00 (I presume SS) units from the usual vendors?

[Joe L.]

Re: 1974 Rear Halfshaft Flange French Locks

Joe,
Are those the $7.00 (I presume SS) units from the usual vendors?

Paul------


I don't recall what they cost. However, if they don't specifically say stainless steel or "SS" and that's what you want, I think I'd inquire before ordering.

[Paul L.]

Re: 1974 Rear Halfshaft Flange French Locks

Paul------


I don't recall what they cost. However, if they don't specifically say stainless steel or "SS" and that's what you want, I think I'd inquire before ordering.

I'll check. I am finding it more and more difficult these days to sort out the "good" parts from the Chinese junk.

Over in CF I documented the recent internal disintegration of my 1974 #1112247 distributor; basically the brass button spread mayhem. The mainshaft and lower bushing were trashed. But heck after 97,000 miles things happen. I had a spare rebuilt unit with Lars' components in the basement so all is well for 2010 and perhaps beyond. The 1974 is running well.

But I wanted to rebuild the old or have a back-up. I am a bit anal on back-up parts as our driving season here is so short. I can't wait for back-orders.

The $95.00 EBay DragonFire HEI unit was tempting. But being old school I ordered ZIP rebuild parts and will fix at my leisure in coming months. After a careful cleaning #1112247 (1974 L-48) will work again. With a new main shaft and lower bushing it will be fine. Other ancillary parts will go on as well. I am thorough.

[Larry M.]

Re: 1974 Rear Halfshaft Flange French Locks

Paul:

Besides the rusting issue, you want the SS french locks because they are more resistant to deformation when tightening the half-shaft to spindle flange bolts. The regular steel will deform at around 55 ft-lbs. I tired everything, including coating with "moly-cote" or never-seize to reduce friction.

I have been told that the stainless steel ones will take the specified torque. You may still want to coat them with a never-seize before torqueing, just in case.

I settled for 55 ft-lbs on these bolts with my regular steel french locks.....but I will use the SS locks on the next go-around.......whenever that is.

Larry

[Paul L.]

Re: 1974 Rear Halfshaft Flange French Locks

Thanks Larry,

Where are the SS available? Generally Dr. Re Build knows the correct restoration drill but I don't see them there. Help!

[Larry M.]

Re: 1974 Rear Halfshaft Flange French Locks

Thanks Larry,

Where are the SS available? Generally Dr. Re Build knows the correct restoration drill but I don't see them there. Help!

Paul:

I checked a number of supplier catalogues............Bair's has the stainless steel ones we discussed. Part # 5291.

Did not see any in DR REBUILD, Paragon, or LICS......although it is possible they may have available if you call.

Larry

[Paul L.]

Re: 1974 Rear Halfshaft Flange French Locks

Thanks Larry. Much appreciated!

[John H.]

Re: 1974 Rear Halfshaft Flange French Locks

Did not see any in DR REBUILD, Paragon, or LICS......although it is possible they may have available if you call.

Larry

Larry -

Paragon has both steel (#249K) and stainless (#13007K).

[Larry M.]

Re: 1974 Rear Halfshaft Flange French Locks

Larry -

Paragon has both steel (#249K) and stainless (#13007K).

Thanks John. Either was older Paragon book was outdated or I missed it. I thought someone else besides Bairs carried them.

Larry