Engine & Accessory Date Coding & Build Process
 

Engine/Trans & Accessory Build Process & Date Code Questions:

With regards to a date-coded restoration, it is important to understand the build process that existed both at Pontiac Engine Assembly and the Vehicle Assembly Plant.

Assumptions/Questions:

- Engine block was transferred from casting plant to engine assembly plant with Engine Unit Number stamped onto front RH face (below cylinder head).

- Engine assembly plant installed bearings, crankshaft, camshaft, pistons, cylinder heads, intake manifold, exhaust manifolds, distributor, timing chain cover, water pump, crankshaft damper, oil pan. Entire assembly was masked where necessary and painted. 2-letter usage code was stamped onto RH face of block below cylinder head along with applying a matching usage code decal.

NOTE: According to Camaro Research Group (CRG), the carb. wasn't installed until the vehicle assy. plant however, a friend who worked at Pontiac Engine Assembly in the 60's told me that he remembers assembling tri-power carb linkage, lines and installing them to the engine at the engine assembly plant. Not sure if this remained true throughout the 60s.

- Engine sub-assembly was shipped to vehicle assembly plant where it was selected according to broadcast and placed onto the engine dress (or build-up) line. Applicable trans. was attached to engine and the partial VIN for each was hand-stamped with the same tool (rolling gang stamp) according to the broadcast sequence for the intended vehicle. NOTE: Since engine was painted at engine assembly plant, VIN characters shouldn't be covered with paint.

- The following parts were installed to the engine at vehicle assembly plant:
Carb. ?,, Alternator, Starter/Solenoid, Coil, wires/wiring, pulleys, A/C & A.I.R. components where required, fan. clutch, flywheel, bell housing, (prior to trans marriage to engine), power steering pump, vacuum fittings, hoses on carb/intake, fuel pump, fuel lines, oil filter/adaptor, oil dipstick/tube, engine/trans mounts, shifter/linkage, radiator hoses, misc. brackets.

For date code matching purposes, based on the assumptions above...

- All engine/trans & accessory parts with cast or stamped date codes should proceed the build of the vehicle (as a general rule, within the week according to Trim Tag code and certainly prior to the Invoice Date). There were exceptions.... part shortages, low-run optional engines, etc.

- All cast dates used the letter "I", (Sept.)...(engine, intake manifold, cylinder heads, exhaust manifolds, water pump). All stamped date codes did NOT use the letter "I".

- Cast engine accessory parts should proceed the engine casting date by 1 week to 1 month or so (or be very close to it). Exceptions may exist.

- The distributor stamped date code should proceed the engine casting date.

- The starter, alternator, steering gear box, oil pressure sending unit (where applicable) may be before or slightly after engine casting date but certainly before vehicle build date week.

Comments, thoughts, critique, corrections?

Thanks!

I have a 68 Tempest 4-Door and a LeMans parts car that is unmolested, here are the dates. They are just 350 engines, but should represent standard sequencing.

.....................................TEMPEST...... ......LEMANS

BODY BUILD...............06C.....................06D
BLOCK..........................E088............... .....F288
INTAKE..........................E078.............. ......F198
RH HEAD.....................E018....................F 248
LH HEAD......................E088.................... F178
RH EX. MANIFOLD E078.................. F278
LH EX MANIFOLD E068...................F278
ALTERNATOR............8D9......................8E2 4
DISTRIBUTOR...........8E02...................8E26

Before going into the chassis, engines were pre run on Propane to pressure up & check for noise. (Per John Sawruk) Seems likely that this was done in Pontiac & this would necessitate an oil filter mount/filter & flywheel. Weren't mid 60's oil filters painted with the engine?

That's a great summary. thanks I have the following comments about the dating. I am not sure if I am contradicting much of what you said or not. My car's dating does follow my thoughts below.

Since most of the engine pieces were cast with a date, then assembled and then shipped to the assembly plant, these pieces are normally dated at least a week and possibly many weeks prior to the car's assembly.

There are likely several "engine casting dates." I do not know why a distributor could not be dated either before or after these dates. My distributor is dated slightly after the heads and intake dates and close to the block date code.

All of the items not shipped from the engine plant are often dated closer to the car's assembly date. I believe this is true of every such part on my car including the carb, starter, alternator, steering gear box, brake booster and rear end. (My oil pressure sender is not the original.)

Very nice summary.

Flexplate (for automatics) or flywheel and clutch bellhousing were installed at the engine plant.

I should mention that there was some variation in which of these components were provided by the engine plant across model years, based on the program team’s direction. The motivation for moving these items back and forth between the vehicle plant and engine plant usually was motivated by the desire to control part number proliferation, or to address cross platform issues that could be dealt with in the most straightforward manner. In other words, if a change to a spark plug wire would proliferate engine assemblies then it would make more sense to do that at the vehicle plant rather than engine plant

Small, complex components coming from outside suppliers should precede the vehicle and engine build dates, since it takes time to build those up and you don’t want to risk running out. Distributors, alternators, carburetors would fall into this category.

The casting date codes do not have to match exactly (like between the cylinder heads and engine block), and will vary slightly based on final assembly location. For example, there is some transportation time to get engines by rail from Pontiac Michigan to Fremont California. On the other hand, engines going into vehicles in Pontiac Michigan can be pretty short lead time.

For my Pontiac Michigan built ’65 GTO, the difference between the block/heads were cast to when the running vehicle drove off the line was 9 days.

K

I am uncertain about an engine build date, but my 1C Judge's heads/intake are Oct. '68, block and the 941 distributor are Nov. '68. The 28273 carb is Dec. '68, and the alternator is Jan. 3, '69--just prior to the car's assembly. I still believe items installed at the build plant are often dated closer to the car's assembly date. But I assume you have seen the opposite, Keith.

I am wondering about the starter date. If they were started and run on LPG at the engine plant, would the starter have been on it there? Or perhaps they had a portable engine cranking mechanism much like the top fuel dragsters use.

There can be significant variations from these rules of thumb. For example my 69 Sprint Firebird (Norwood assembly in June 69) has the engine block and other major engine components dated December of 68, 7 months earlier. (100% certain that it is the original engine with VIN etc clearly original. Another 69 Firebird (TA) I have has less extreme but similar situation (car was built in Norwood in September 69, but engine block and components all date from late May to early June.)

Are we certain that all engines were pre-run at the engine assembly plant?
I'll have to ask my friend who worked at Pontiac Engine Assembly in the early to mid 60s.
I recall him saying one of his jobs was sub assembling the Tri-Power carbs, lines, linkage and setting the entire assy. into a rack where another operator would place it on the engine/intake.
He also swung the mallet to stamp the engine usage code on the front of the block. Said they Engine Unit Number was already stamped before it got to him (at casting plant?)

I think the carb(s) weren't on the engine when ran?
Not sure if intake was on or special contraption (for propane)?

:confused:

Bet Winner, the dates of the engine castings & the factory use of the Fall dated 1941 distributor on an early RAIII engine is the absolute norm. The 1941's were also the factory installed distributor in a BUNCH of '69 WT engines installed in late Fall of '68 and the early Winter, factory uses well before the RAIV engine was released. Over the last 30 years, I've noted the mid to late J and early K casting dates on nearly a dozen original early '69 usage WS & YZ engines.

There's a thread on this forum somewhere where there is a notation of when the first non Judge availability of the RAIII engine was, & believe it was only shortly before the actual builds of '69 Judges. My own observation is what we're seeing with all the mid to late Oct & early to mid Nov dated blocks, & "48" head castings, on these engines is the result of a very well thought out engine building & stockpiling by Pontiac in anticipation of the release of the Judge. The very first '69 YZ engine I noted this on was in the early 90's. Original late J, early K casting dates on the original engine to a March built (non pattern) Judge built out of Lakewood Plant. Had its original K dated 1941 distributor as well.

Every time, I read a poster's "generic" date range recommendation for engine component dates, am sorry I have a good chuckle & think back to factory built deals like these early '69 RAIII builds. Similar deal when there is a "my Master Parts Book lists this distributor in an early '69 RA III engine" topic. Its time to get ones head out of the parts books and listen to hands on guys , i.e; Master Parts Books didn't build the cars, they listed Service parts for the original cars.

Intakes were on & painted with engine. They used some sort of rubber "mask" over the intake to run up the engine.

This Eric White interview with Pontiac factory worker Carl Papke is on Wildaboutcarsonline.com They talk about running the engines without a carb but on a natural gas / air mixture and water hoses hooked up. It is a very good series of articles with lots of info about the various plants. However, what years that this was done is not stated in the article, so unsure if every engine from that plant was fired. He also states they didn't have a starter on them at that time. Hmmmmmm...... I wonder if the starters were installed at the assembly factory then.

Engine fire up is about half way down Section 4.

http://wildaboutcarsonline.com/cgi-b...aldisplayed=50

And here is a link to section 1 - the start of the interview. The series pretty much traces the construction of the car from the frame to finished. This may help with some of the OP's questions about the build process and dates etc. It says factory worker Carl started working at the pontiac factory in Oct. 1963.

http://wildaboutcarsonline.com/cgi-b...aldisplayed=50

There are examples of parts listed in the Master Parts Book that were never built!!! Try finding a 7040278 carb. ;)

The absolute authority in literature for what went on what and when, are the Plant Inspector's Guides; but these are a wee bit difficult to obtain. In 50 plus years of collecting Pontiac factory literature, I think I have acquired only 7 different, all in the 1960's. The hold notices are also quite useful.

Jon.