Rebuilding the 1949 Buick 248 Straight 8 Engine

NEW PERSPECTIVE ON AN OLD ENGINE

1949 Buick 248 Straight 8 Rebuild

Most people have never seen inside a straight 8 engine. Although this isn't the first one we've re-built at Driven Restorations, we are the FIRST to dig into THIS particular ALL ORIGINAL Buick engine and the photos in this blog post let you see it first hand. 

It feels like opening a time capsule as we excavate to the depths of the engine, revealing parts that haven't seen open air since being pieced together on the assembly floor in 1948.  

RESCUED AT LAST!
The '49 Buick emerges from storage

Those very parts transported the Buick's family all over Oklahoma, coating her undercarriage in layers of clay and speckling her body with dings along the way. We've been told a few stories hinting that there may have been some shenanigans resulting in a couple of LARGER dings and one particular joy ride ended in her engine to running low on oil (was it low or empty?). The Buick's original 248 never ran the same again. It seemed her fate was to remain shoved, nose first, in the storage garage. 

Lucky for us, she was rescued.

 It's hard to believe, but members of the very same family who enjoyed this Buick for decades not only kept the car, but they've decided to honor her with a frame off restoration at our shop!

She will be GLORIOUS 

In the photos that follow, we take you from tear down through a fresh coat of paint as we meticulously re-constructed the heart of the '49 Buick, it's original 248 Straight 8. 

*THIS IS NOT INTENDED TO BE A COMPLETE GUIDE TO REBUILD YOUR ENGINE, BUT RATHER A VISUAL GUIDE TO BASIC STAGES
**All photos are taken at our shop at Driven Restorations LLC Fall of 2017.

STEP 1: CLEANING!

Before we can undo the bolts, or even find them, we had to un-earth the engine from beneath layers of 1-3" thick and firmly packed Oklahoma clay. 

Arrived at Driven Restorations: 1949 Buick Special 40 Series 
Under the hood is the all original Buick straight-8, 248 c.i engine

As we venture further under the hood, we remove mouse droppings, piles of leaves and paper wasp nests, more droppings (these were bigger...ick), rodent graveyards, COUNTLESS rodent nests built from seat stuffing,  2 inches of battery corrosion, and a dusting of WI pollen and stray corn husks for good measure. By now, you should feel remarkably lucky that you can't smell what this Buick has wafting from every opening. 

Engine bay AFTER cleaning:
Yep... Still dirty! Ugh!
That orange glow is not rust,
it's red clay.

Engine bay BEFORE cleaning
(This could be a challenge)

We removed the radiator, several brackets, trim parts, and a few sections of the grill assembly to make way for the awkwardly shaped, extremely heavy, engine to be removed without causing any body damage.

As for the clay,  it's pretty easy to tell where the pressure washer couldn't reach. This engine is FAR from clean and the clay wont come off without a LOT of persuasion. Guess it's time to get out my rubber gloves, stiff bristle brush and favorite scraper. 

STEP 2: TEAR DOWN

LET THE EXCAVATION BEGIN!!!!

During disassembly watch for cracks, popped freeze plugs or any signs of stress (like the blackened rocker assembly we found). Photograph the "oddities"  as you go. 

Label all parts you remove. Even if you wont re-use that actual part, they will be needed to ensure the replacement parts match your application.

Scraping the clay...still scraping... removed the valve cover...
YUCK. Top end looks burnt. This is the result of running out of oil on one occasion...that we know of. Although expected, it's still not a pretty sight.

Cleaning the head after removing it from the engine

Crank removed. Time to clean!Again.
I'll get my gloves 😐

Disassembly continues with removing the rocker assembly and push rods. Check for any bent or defective parts as you remove these delicate parts, especially when they are as discolored as the ones shown.

The end of disassembly is within site. That's the original Buick Blue paint peeking out from the last layer of clay

The verdict on our engine? Overall the block and internal parts were in great shape, but we discovered 2 areas of concern 

including a very overheated rocker arm assembly and a cracked manifold.

STEP 3: PARTS ID AND REPLACEMENT

Q: BABBITT OR INSERT BEARINGS?

This particular '49 Buick, although tagged in '49 was built in '48. We used the serial number on the engine to find out if we would have babbitt or Insert bearings.  We had a 50/50 chance based on date codes, but the serial number's rarely lie. 
From the site Straight 8 Engines here's a summary of 248 changes around '48-'49:

"1948 - A new "Flex-Fit" oil ring was fitted to the pistons, an improved oil filter was installed, and a new engine/transmission assembly rubber-mounting system was installed which dampened engine and road vibrations to provide passengers a smoother ride.  This year also marked the first use of the Dynaflow automatic transmission. 

1949 - Insert-type bearings replaced the poured babbit bearings in the connecting rods in mid-1949."

We guessed this block would contain babbitt bearings. This was an "early '49" assembled car, with most of it's parts made and assembled in 1948. Our prediction of finding babbitt bearings was indeed correct.

What is a Babbitt Bearing?(I'll let Wikipedia Explain)

Original '49 Buick 248 Pistons
with Babbitt Bearings Sleeves

Original '49 Buick 248 Pistons, 
showing the "flex fit" oil 
ring noted in the quote
above for 1948 improvements 
to the 248

Original '49 Buick 248 Pistons

Original '49 Buick 248 Pistons: Pointing out babbitt sleeves

 The original set of pistons were cleaned, boxed up as core exchanges and sent out to the East Coast.

The exchanged insert type bearing pistons arrive for the bored out 248c.i engine. We sent in the original pistons as core exchange for a full set of correctly sized, insert type bearing pistons. 

248 engine block and crank have been lightly cleaned by us in the shop to inspect for cracks or damage (😓 so much cleaning!). They look great so they are ready to go out to the machine shop

TIPS for BUYING PARTS and ENSURING PROPER FIT after MACHINING: 

1. YOU MUST KNOW THE BORE OF THE BLOCK AND GRIND OF THE CRANK BEFORE ORDERING PISTONS, RINGS AND RELATED PARTS
As an example, our specs for this application: 

• Crank ground 0.10 
• Block bored 0.20 over

The pistons and rings we ordered to spec per our machine shop's final bore on the block. Depending on engine wear, you may have to be more aggressive with the bore to achieve a "clean" surface. 0.30 is a fairly standard bore to start

For this application we did the 0.20 bore because the 0.30 bore was out of stock for the foreseeable future. 

*You may want to check on parts availability with your supplier before selecting a bore (if you have a choice)

TADA! THE BLOCK AND CRANK ARE ALREADY BACK!
Just kidding...It took a couple months in real time, which is relatively fast for a machine shop that time of year. 

INSPECT BEFORE YOU ACCEPT!

Whether you pick them up yourself from the machine shop/store/ re-builder, or the parts are shipped to you, ALWAYS INSPECT them to be sure you're happy with the result and count them to verify that you received every part you sent out.

Never apologize for inspecting. Some shipping carrier's may be impatient as you unpack your parts. Remember, it's their job to delivery things intact or return to sender if there is a problem. 

Rocker arm assembly re-built
via a service in the North East

We use trusted partners with a proven track record of of quality work. Sticking with one service provider can help ensure your specifications are met and the work gets done quickly, but they are still humans! So, the rule to inspect everything still applies. When we picked up the engine block and crank we double checked that all measurements were within the spec, the parts were clean, and the block was unpainted (A+ for our engine machine shop again!)

WHAT ARE YOU LOOKING FOR UPON INSPECTION?

• ACCURACY: Engine measurements will impact every other part of your engine (bore and stroke matter!). If they are wrong they must be corrected before assembly, otherwise you can plan on doing this re-build again in the very near future.

• COMPLETENESS: On more than one occasion we have received a box with a hole or ripped tape. We've dealt with broken or missing piston rings, missing hardware, and even missing valve springs that got set aside during cleaning and never made it back into the box. (Very frustrating!!!)You think you're ready to assemble...and then suddenly you're not. Before you ship parts for re-build take the following steps as insurance:
• Label parts going in the box
• Photograph what you are sending out with labels visible
• Write an inventory of parts you are sending
• Record the date of shipment
• Note the expected date of return

Buick 248 head after machining and inspection

STEP 4: ASSEMBLY

Assembly has a natural progression. In the photos that follow, you'll notice that Steve starts at the "bottom", with the crankshaft, following the assembly instructions per the Buick Shop/Service manual. As seen in the photo below, Steve pre-assembled the engine head

Steve setting up for assembly of the Straight 8 Buick 248

Crankshaft Installed in the 248

TIPS FOR AN EASIER ASSEMBLY

1. "Clean Room" or at least a VERY clean work area: 
• Dust and debri are the enemy of a long lasting, functional engine. Do not get dirt, metal shavings, hardware, tape...or ANYTHING inside the engine that isn't supposed to be there.
2. Assembly lubricant and rubber gloves
• Latex gloves are a handy thing to keep in the shop
3. Heavy Duty Engine stand:
• Capable of supporting a Straight-8 Buick engine FULLY ASSEMBLED. These are HEAVY with quite awkward weight distribution. 
• In a pinch, custom fabricated engine cradles work very well, just make sure your welds are solid!
4. Organizer tray/tool cart
•  Lay out ALL machined parts, cleaned, labeled and in order of installation (per instructions and parts labels). 
5. Gaskets and gasket set/liquid gasket
• An engine cannot be assembled without it's gaskets, hopefully that's obvious...If it isn't obvious, back away... slowly.
6. Hardware
• Ensure you have the right number of each piece of hardware
• Sort hardware according to the parts they will attach 
•  Check threads: Any bolts broken off in the block? 
• Re-thread bolts/bolt holes as needed being conscious of metal shavings and keeping the block clean
7. Instructions and Assembly Manuals
•  Review any instructions that came back with parts that were re-built. 
• At times, small changes in metals (modern vs '48) can modify assembly procedure's from the standard shop manual process typically used. (type of lubricant, order of assembly, size of bolts/ parts etc) 
• Know what your "new" used parts need in advance.
8. Your phone 
• Phone a friend if you get stumped 
• Look up additional photos or instructions as needed. 
9. Time and lighting
• Set aside at least 4 hours in your clean, well lit  work space to complete the initial assembly 
• Bonus points if your work space is free of distractions like food, kids, dogs... you know, all the things that are in our shop photo during piston installation below! Oops 😥
10. Get your tools and get started! 
• Hopefully you took time to review the shop manual which might list a tool (or two) that you don't currently own.
11. When in doubt...call Steve. (It's what I would do😉)

Ensure that you set yourself up for success instead of a headache. Prepare your work area, set out your tools and organize your parts, however, if you started the process and quickly realized you're in over your head on this one...(No specialty tools for '49 Buick engine's just lying around or the time you had suddenly vanished?) Stay calm...we can help with that. Just follow the emergency procedure below:

• Put everything down where you found it and go get yourself a "STEVE" of your very own! He not only assembles Straight 8 Engines, but he's done straight 6's for Chevy trucks, Small blocks and built big block powerhouses. 

Assembly in progress: 
Steve is "knocking" the piston's into place and Hanna making sure everything stays lined up. She's also keeping an eye out for broken piston rings in the process of installation. Even new parts can fail during assembly.
The baby was supervising. She's smiling because they were ALMOST done!

248 Block with new pistons installed

Cam Shaft installation in the
Straight 8 can be tricky. This is
due to the progressive bearing
sizes. Be sure you do not
 damage the lobes or break
a bearing when installing.
Patience may be required.

With the cam in place the timing gear and chain are installed, then the timing cover is installed (next photo). All sheet metal parts are in acid etch primer (dark gray), ready for paint with the rest of
the block.

The block is almost ready for paint! Rocker arm assembly and push rods are in place. Next, we clean the block with degreaser (yes, cleaning again) then mask off the manifold openings and anything else that shouldn't be blue or get paint in it (threaded openings should be covered/plugged)  then set the valve cover. De-grease again, then you're ready for paint! 

STEP 5: PAINT 

We apply the color using our favorite engine enamel***** applied via HVLP paint equipment in our booth.

(Sorry, we're keeping our secret paint brand a secret...for now). 

The Original "Buick Blue" applied to the engine

For best results pay close attention to PREP. Clean and de-grease thoroughly then mask all openings and insert hardware in threaded holes. Use your favorite rust proofing High Temp Paint. Aerosol paints will work if you don't have other paint equipment. 

〈Need more info from a Buick Database?〉

TRY THE FOLLOWING LINKS

• Timeline of the Buick Straight 8 Engine and details on it's specifications

• BEST FORUM OUT THERE: AACA Forums  
• Search friendly Q/A threads (a fancy name for an online conversation if you're "uninitiated"), friendly and responsive users (within days to a week usually) and a great resource for rare parts, assembly photos for reference and a wealth of historical knowledge. You will have to register if you need to post questions.

• Photo gallery of an original *mostly* complete '49 Buick Special Series 40 which happened to be for sale recently. Helpful photos but ask the Buick forum listed above if you need detailed information on parts/installation: Sunset Classics 1949 Buick Gallery

• Original spec database for '49 Buick's: Classic Car Database

• Paint colors based on original Buick Body Code tag

Still have questions or need someone to help get your Straight 8 back on the road? email us at drivenrestorations@gmail.com