Carburetor varnishing and fuel delivery failure
high- Typically appears
- Any — storage-driven, not mileage-driven
- Estimated repair
- $200 – $800
1928 Cadillac
Series 314Roadster
341 CI V8 · Roadster
The 1928 Cadillac Series 314 Roadster is a pre-Depression-era American luxury automobile powered by Cadillac's landmark 341 cubic-inch (5.6L) L-head V8 — a smooth, relatively advanced engine for its day. The 'Series 314' name carried over from the earlier 314 CI displacement era, though by 1928 Cadillac had bored the engine out to 341 CI while retaining the Series designation. The Roadster body style seats two (with a rumble seat option) and represents the open, sporting expression of the lineup, finished by coachbuilders to Cadillac's chassis specifications. This is a collector and show vehicle, not a daily driver. Parts are almost exclusively sourced through vintage suppliers, specialty restorers, and marque-specific clubs like the Cadillac-LaSalle Club. Mechanical systems are entirely pre-electronic: no OBD ports, no fuel injection, no power anything. Every repair is hands-on craftsmanship work. Owning a 1928 Series 314 means joining a community of dedicated enthusiasts. Expect to budget for specialist labor, NOS or reproduced parts, and long-term storage solutions. In a climate like Lake Geneva, Wisconsin, proper winter storage is not optional — it is the single most important thing you can do to preserve this car.
Reliability
3/5
Verified data
Engine
341 CI L-head V8
Drivetrain
RWD
Fuel
Gasoline
MPG
8 city / 12 hwy / 10 combined
Seats
2
Doors
2
Body
Convertible
MSRP
$3,295
Overview
AI-curatedThe 1928 Cadillac Series 314 Roadster is a pre-Depression-era American luxury automobile powered by Cadillac's landmark 341 cubic-inch (5.6L) L-head V8 — a smooth, relatively advanced engine for its day. The 'Series 314' name carried over from the earlier 314 CI displacement era, though by 1928 Cadillac had bored the engine out to 341 CI while retaining the Series designation. The Roadster body style seats two (with a rumble seat option) and represents the open, sporting expression of the lineup, finished by coachbuilders to Cadillac's chassis specifications. This is a collector and show vehicle, not a daily driver. Parts are almost exclusively sourced through vintage suppliers, specialty restorers, and marque-specific clubs like the Cadillac-LaSalle Club. Mechanical systems are entirely pre-electronic: no OBD ports, no fuel injection, no power anything. Every repair is hands-on craftsmanship work. Owning a 1928 Series 314 means joining a community of dedicated enthusiasts. Expect to budget for specialist labor, NOS or reproduced parts, and long-term storage solutions. In a climate like Lake Geneva, Wisconsin, proper winter storage is not optional — it is the single most important thing you can do to preserve this car.
Known for
- Silky smooth 341 CI L-head V8 — a landmark American engine of its era
- Coachbuilt luxury with hand-fitted wood framing and fabric or leather bodywork
- Imposing pre-war presence and strong Cadillac marque prestige
- Mechanical simplicity relative to modern vehicles — no electronics to fail
Best for
- Seasoned collectors with a dedicated, climate-controlled garage
- Show car and club concours participants
- Drivers who enjoy hands-on, old-school mechanical work
- Special occasion and parade use
Watch for
- Wood body framing rot — the core structural concern on any surviving example
- Originality of drivetrain components; many cars have been re-engined or modified over 95+ years
- Brake system: mechanical four-wheel brakes only — stopping distances are dramatically longer than any modern vehicle
- Fuel system degradation from sitting; varnished carburetors and rotted fuel lines are nearly universal on unmaintained examples
- Electrical system: 6-volt positive-ground — incompatible with modern accessories without conversion
Common issues by mileage
6 knownWood body frame rot or structural softening
high- Typically appears
- Any — age and moisture-driven
- Estimated repair
- $2,000 – $15,000
Mechanical brake adjustment and lining wear (non-hydraulic)
medium- Typically appears
- Any — requires regular adjustment
- Estimated repair
- $300 – $1,200
6-volt electrical system failures — generator, wiring insulation cracking
high- Typically appears
- Any — age-driven
- Estimated repair
- $150 – $2,500
Rubber seal, gasket, and hose deterioration (coolant, fuel, vacuum)
high- Typically appears
- Any — rubber compounds degrade over decades
- Estimated repair
- $200 – $1,500
Valve guide wear and oil consumption (L-head engine)
medium- Typically appears
- High use or post-long-storage
- Estimated repair
- $800 – $3,500
Maintenance schedule
- 1 Every 1,000–1,500 miles or annually Change engine oil with straight-weight non-detergent oil
Pre-war flat-tappet L-head engines require non-detergent, zinc-rich (ZDDP) oil. Modern multi-viscosity detergent oils can dislodge accumulated sludge in old engines and cause bearing damage. Use a grade appropriate to season (SAE 30 summer, SAE 20 winter).
- 2 Every 500 miles or at start of each driving season Grease all chassis zerk fittings
The 1928 chassis has numerous grease points on kingpins, tie rod ends, and U-joints that must be lubricated manually. Neglecting these leads to rapid wear of irreplaceable or difficult-to-source components.
- 3 Every season or any time stopping distance increases Adjust mechanical brakes
Mechanical four-wheel brakes have no self-adjusting mechanism. They require periodic manual equalization across all four corners for safe, straight stopping. This is a safety-critical task.
- 4 Annually, and before any storage period Inspect and clean carburetor and fuel strainer
The single-barrel carburetor is prone to varnish buildup from ethanol-blended modern fuel. Use ethanol-free fuel where available (common at marine and aviation suppliers in the Lake Geneva area) to reduce this significantly.
- 5 Before each driving season and before storage Test and charge 6-volt battery; inspect all wiring
6-volt systems have less reserve capacity than 12-volt. Cold Wisconsin winters will kill an aging 6V battery fast. Inspect cloth-wrapped wiring for cracking and rodent damage every season — fire risk is real on unprotected old wiring.
- 6 Every 2 years Flush and refill cooling system
The engine has no corrosion inhibitors built into the block design. Old coolant becomes acidic and accelerates corrosion of the cast-iron block and radiator. Use a non-silicate coolant compatible with older metals.
- 7 Annually Inspect and re-treat canvas top and body seals
The Roadster's fabric top is structurally part of weatherproofing. UV degradation and moisture intrusion onto wood framing is the primary cause of body structural failure on surviving open cars.
- 8 Every 3–5 years or after any purchase Full mechanical inspection by a pre-war specialist
General mechanics are not equipped to service pre-war vehicles. A specialist familiar with L-head V8s, mechanical brakes, and pre-war electrical systems will catch problems that modern shops will miss or misdiagnose.
Always defer to the manufacturer's service manual for warranty-mandated intervals.
Cost of ownership
Annual maintenance
$800 – $5,000
Fuel
Low annual fuel cost due to very limited use; however, the engine gets approximately 8–12 MPG and requires ethanol-free premium where possible (roughly $0.20–$0.50/gallon premium over regular). Budget $100–$400/year for typical show/pleasure driving mileage.
Insurance
Collector/agreed-value insurance through a specialty insurer (Hagerty, Grundy, etc.) is strongly recommended over standard auto policy. Annual premiums for a well-restored example typically run $300–$800/year depending on agreed value and mileage restrictions.
Day-to-day running costs are low because this car covers very few miles. The real cost is in restoration, specialist labor, and storage. A climate-controlled garage in Lake Geneva is essential — heating costs aside, the alternative is wood rot, rust, and a car that depreciates into a parts donor. Budget $1,500–$3,000/year for a well-maintained example in active show use; a car coming out of dormancy or needing restoration work can easily run $10,000–$50,000+ to bring to proper standard.
Seasonal care
Lake Geneva, WI Winter
- Full winter storage is mandatory in Lake Geneva's climate. Do NOT attempt to drive on salted roads — road salt will destroy irreplaceable tin and body components within a single season.
- Drain or treat the fuel system before storage: either drain completely and fog the carburetor with light oil, or fill the tank with ethanol-free fuel and add a fuel stabilizer.
- Change the oil before storage, not after — used oil contains acids that attack bearing surfaces over a long sit.
- Remove the 6-volt battery and store it on a trickle-appropriate maintainer indoors. Cold discharge will destroy an already marginal 6V battery.
- Store on jack stands if storing longer than 3 months to prevent flat-spotting of tires and unloading the springs.
- Use a breathable cotton car cover — never plastic — to prevent moisture trapping against the body and canvas top.
Summer
- Check tire pressure before every outing — bias-ply or vintage-spec tires lose pressure more readily than modern radials and are critical to safe handling on a car with mechanical brakes.
- Monitor engine temperature closely: the cooling system has no overflow reservoir and early signs of overheating are easy to miss. Carry extra coolant.
- Inspect the canvas top for UV cracking before summer show season and treat with an appropriate fabric protectant.
- Check all grease fittings and oil levels before any long drive — there is no warning system to tell you when something runs dry.
- Keep a basic toolkit and spare parts (points, condenser, spark plugs, fan belt, extra fuel line) in the car or support vehicle for any drive over 30 miles.
Comparable vehicles
1928 Packard
526 Six
Direct luxury-market rival in the same era; similar coachbuilt construction, mechanical brake system, and collector community. Packard had arguably stronger brand prestige in 1928 and comparable parts/club support today.
No catalog match1928 Lincoln
Model L
Ford's flagship luxury marque in 1928, also V8-powered (385 CI L-head). Similar price point when new, similar collector value today, and a comparable ownership experience. Strong Lincoln club support.
No catalog match1929 LaSalle
Series 328
LaSalle was Cadillac's companion marque, sharing the same GM platform and many drivetrain components. Parts often interchange, and the Cadillac-LaSalle Club covers both marques — making it the closest practical cousin to the Series 314.
No catalog match1928 Pierce-Arrow
Series 81
Top-tier American luxury of the same era, coachbuilt to order and similarly collectible. More rare today, which means higher values but harder parts sourcing. A natural comparison point at concours events.
No catalog match