Trying To Find The Timing Marks On The Distributor and Intake Manifold On My 66 L75

[David H.]

Re: Trying To Find The Timing Marks On The Distributor and Intake Manifold On My 66 L

On my 1980.

[John S.]

Re: Trying To Find The Timing Marks On The Distributor and Intake Manifold On My 66 L

[Philip A.]

Re: Trying To Find The Timing Marks On The Distributor and Intake Manifold On My 66 L

I’m surprised this isn’t a judged item. There are so many other seemingly obscured features listed in the judging guides.

Yeah, chisel mark is NTP (too deep, too shallow, too wide, too thin, too far left, too far right, etc)

[Larry E.]

Re: Trying To Find The Timing Marks On The Distributor and Intake Manifold On My 66 L

With the help of my new tool>General Tool#80560(See Below) I DID FIND THE CHISEL MARKS on
my 66 Base Engine Coupe which has a build date of 9/20/65. Best way to find these marks is to take
some of the Ignition Shielding off and approach to find the marks from the Passenger side of the engine.
The tool below makes it easier because of the light is generated at the mirror source. The marks are
very small like John Sigmund picture above. Thanks Again>Larry

[Owen L.]

Re: Trying To Find The Timing Marks On The Distributor and Intake Manifold On My 66 L

Like to hear from other C2 owners if they
have seen them on their cars.

I'm fairly certain my '67 390 has it. I replaced intake gaskets and tuned the distributor last spring and seem to recall that it coincided with my distributor timing experiments. I don't recall seeing it on my '72...

[Patrick B.]

Re: Trying To Find The Timing Marks On The Distributor and Intake Manifold On My 66 L

The marks are on my 67 L-71 and 70 LT-1, and I have noticed them on other engines and loose manifolds. I have always assumed that all Chevy engines had this feature.

[Mike M.]

Re: Trying To Find The Timing Marks On The Distributor and Intake Manifold On My 66 L

i just examined all 7 our our fuel injected corvettes. the four 57's have no chisel marks on the intake/base plate nor on the distributors. And the three 65 FI's don't have chisel marks on their intake/base plates, nor on their aluminum distributor spacers, nor on their distributors. mike mccagh

[Mark F.]

Re: Trying To Find The Timing Marks On The Distributor and Intake Manifold On My 66 L

The distributor installed on the engine at St Louis was supposed to be the same one installed at the engine assembly plant with one exception. If Transistor Ignition (K66) from 1968 to mid-1969 the TI distributor was installed at St Louis. In that case the points distributor was sent back to the engine assembly plant. And yes the purpose is for clearance on the rack that the engines are shipped in.

Larry Excerpt below is from a John Hinckley article on "Small Block Assembly Overview". Text is towards bottom under "HOT TEST". Article can be found on Camaros web site - link below. Dave - The operators then fired the engine, checked for oil pressure and oil or water leaks, set the timing, tightened the distributor hold-down clamp and chisel-staked the reference mark on the distributor base and intake, and listened for any unusual noises. Oil and water were drained, all test adapters were disconnected, and the engine was hoisted out of the test stand and placed on another conveyor that took it to the shipping area. Engines needing further attention due to test discrepancies were set aside for repairs; when repairs were completed, those engines were re-tested and sent on their way. http://www.camaros.org/flintV8.shtml

Thanks Terry and Dave,

I have re-reviewed my stuff on John Hinckley's Corvette Assembly process presentations and also Dave's link to the Camaro site

Let me see if I have this right...

1. Flint and Tonawanda installed points distributors on all engines
2. Hot test them at the engine plants with those distributors in place
3. remove them for shipping to St. Louis
4. then ship to StL.

Here's where I get confused...(at least for '67s)...

AIM UPC K66 sheet A4 ('67) Step #4 instructs the line worker (presumably on the Engine Dress Line) to remove the points distributor and replace it with a TI K66 distributor. (see attachment below)

So, were the points distributor re-installed upon St. Louis arrival and the un-installed for K66 optioned cars as discussed in attached AIM sheet ?

There were 5,759 K66 cars in '67 (roughly 25% of total production), so it seems a very inefficient process...

There must be a good reason though, eh ?

Anybody have any ideas ?

K66 remove points distributor - replace with TI.pdf

[Terry M.]

Re: Trying To Find The Timing Marks On The Distributor and Intake Manifold On My 66 L

Thanks Terry and Dave,

I have re-reviewed my stuff on John Hinckley's Corvette Assembly process presentations and also Dave's link to the Camaro site

Let me see if I have this right...

1. Flint and Tonawanda installed points distributors on all engines
2. Hot test them at the engine plants with those distributors in place
3. remove them for shipping to St. Louis
4. then ship to StL.

Here's where I get confused...(at least for '67s)...

AIM UPC K66 sheet A4 ('67) Step #4 instructs the line worker (presumably on the Engine Dress Line) to remove the points distributor and replace it with a TI K66 distributor. (see attachment below)

So, were the points distributor re-installed upon St. Louis arrival and the un-installed for K66 optioned cars as discussed in attached AIM sheet ?

There were 5,759 K66 cars in '67 (roughly 25% of total production), so it seems a very inefficient process...

There must be a good reason though, eh ?

Anybody have any ideas ?

[ATTACH]113393[/ATTACH]

Mark
My understanding is that at the engine plant(s) all engines (up until mid 1969 MY production) except those engines with TI as part of thee engine package (L71) were hot tested and timed with points distributors. Those distributors were then removed from the engine and placed on the intake manifold and the engine and distributor were placed in a shipping rack. The pictures I have seen show nine engines per rack -- three wide and three high. At St Louis if the car was to be equipped with K66 a TI distributor was installed and the points distributor was sent back to the engine plant(s). That is the page you reference. I assume a group of distributors were accumulated and placed on one of the shipping racks as the racks were being returned to the engine plant(s). I think it is also reasonable to assume those returned points distributors found their way to other engines. That would/could result in two chisel marks and add to the confusion of this discussion.

Mid 1969 Chevrolet recognized the inefficiency of this process as the number of TI installations increased. A list of engine suffixes was instituted at that time for engines equipped with TI and the TI distributors were installed at the engine plant(s). No more back and forth with points distributors, but the distributor still had to be removed for clearance on those recks.

I was told that another reason for distributor removal was to reduce the chances of damage. With no carburetor on the engine the distributor would be the high point of the assembly and the most likely to receive damage.

As you are looking at the 1967 AIM there will be a page in the basic engine section that instructa the line worker to install and line up the chisel marks. I had intentions to look up the 1968 AIM to give you a UPC number and sheet number to get Close to the C2 sections to make it easier to look up. That might help determine when this process began if someone with earlier AIMS can find that page. Unfortunately, I will have only one night home this week (it is a great Corvette week, but not so good for family life), but first chance I get I will take the time to look that page up in the earliest aim I have. I do have a 1967 Chevelle AIM, but I doubt a page from that would carry much weight here. So 1968 it will be, when I can.

[Mark F.]

Re: Trying To Find The Timing Marks On The Distributor and Intake Manifold On My 66 L

Hi Terry,

Thanks much...I sent you an email (not PM) with some info attached...