67 French Locks on Manifolds

[Kirk M.]

Where in the AIM are the French locks on the manifolds called out? I've looked through the engine section three times and don't see it. Does anyone have a picture of these mounted? Can someone tell me exactly how the go on the manifolds. Also, are they suppose to be painted black? Thanks.

Kirk

[Joe L.]

Re: 67 French Locks on Manifolds

Where in the AIM are the French locks on the manifolds called out? I've looked through the engine section three times and don't see it. Does anyone have a picture of these mounted? Can someone tell me exactly how the go on the manifolds. Also, are they suppose to be painted black? Thanks.

Kirk

Kirk-----


You can look in the AIM until the "cows come home" and you won't find a thing regarding french lock installation. You would need an ENGINE ASSEMBLY MANUAL for that information and those are not generally available. The french locks were installed at the engine plants.

Installation is quite simple, though; they are installed on the last 2 manifold bolts of both ends of both side for BOTH big blocks and small blocks. I'm not really sure that late 1967 big blocks had the french locks. However, everyone else seems to be sure of it, so they may be right.

[Kirk M.]

Re: 67 French Locks on Manifolds

Connecting bar up or down and are washers used? If washers are used, do you need washers on the other bolts as well to even things out? Thanks.

[Joe L.]

Re: 67 French Locks on Manifolds

Connecting bar up or down and are washers used? If washers are used, do you need washers on the other bolts as well to even things out? Thanks.

Kirk----

The "connecting bar" goes DOWN on a small block. No washers are used in conjunction with the french locks. In fact, you can prove this to yourself. If washers were used, it would not be possible to properly bend up the tabs on the french locks so that they lock the bolts.

[Timothy B.]

Re: 67 French Locks on Manifolds

Kirk and Joe,

I always thought washers are used, that arrangment is manifold, washer, french lock, bolt.

[Joseph T.]

Re: 67 French Locks on Manifolds

I believe washers were used underneath the french locks to prevent the french locks from becoming mangled when the bolt is tightened. As mentioned previously, Exhaust manifold,washer,french lock, bolt on both big and small blocks. This allows you to bend the french lock tabs.

[Stephen L.]

Re: 67 French Locks on Manifolds

French locks are used on BB in 67.

Sequence of assy:

manifold
thick washer
french lock
bolt

Photo below.... tabs not yet bent over the bolt head, but should be.

[Kirk M.]

Re: 67 French Locks on Manifolds

Sorry for my stupidity here, but I have not seen these installed before so I'm try to get it straight in my head. Do I have it correct:

1. Gasket
2. Manifold
3. On outer two manifold bolts
- washer
- French lock
- Bolt
4. Bend up tabs to prevent bolts from backing out

Is that correct? Does anyone have a picture? Thanks.

Kirk

[Terry M.]

Re: 67 French Locks on Manifolds

Just say NO to a gasket

[Stuart F.]

Re: 67 French Locks on Manifolds

I was wondering the same thing. I can't recall the last time I used gaskets with cast Iron (stock) exhaust manifolds, at least on a small block. Have no idea about BB's.

I had my manifolds off last about 1992 for refinishing. I used new washers, french locks and bolts at that time, according to my records, but no gaskets. As long as they are not warped, there should be no need. Even then, if they are, they should be milled true before reapplying. Now with headers, that's another story.

Stu Fox

[Kirk M.]

Re: 67 French Locks on Manifolds

Was making reference to an engine re-build book I was checking out last night to see if they mentioned the French locks. Their pic showed a gasket between the manifold and block. Don't believe mine actually has a gasket either - so delete the gasket. Just wanted to get the sequence correct. From the pic it appears the lock is up in BB, but DOWN in SB. Correct? Thanks.

[Timothy B.]

Re: 67 French Locks on Manifolds

Kirk,

Before you install the exhaust manifolds lay a straight edge across them and make sure they are flat. If not you can file flat or machine shop.

[Gerard F.]

No French Locks on my 67 327/300

Kirk,

I have a late June 67 which I've owned for nearly 40 years now. Exhaust manifolds have never been removed. The engine has manifold bolts with a shoulder head which would obviate to purpose of the french locks.
My car never had french locks on the manifold.

Take a look at the second archive thread below for a picture of the manifold and bolt without french locks.

I ain't putting french locks on a car which never had them, and any judge is at least going to get an argument from me, before he deducts points.

[Jim D.]

Re: 67 French Locks on Manifolds

I have a June 1 67 300 hp BG survivor does not have French locks. However my 67 427 a november 66 car does.

[Mike M.]

Re: 67 French Locks on Manifolds

Kirk,
Tim, Joe and Steve have it correct.
In addition, ONLY ONE of the two tabs was bent-over.
That one being the one that lines-up best with one of the flat sides of the bolt head.
HaND