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The Rear-Engine, Air-Cooled 1965–69 Chevrolet Corvair

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Perrya knows a fair amount about the Corvair, America's aluminum-engine classic car.

Inside the Corvair

Inside the Corvair

The Corvair Experience

Odds are if you are under 40, you have never even heard of a Chevy Corvair, as they stopped making them in 1969. Some 20-30-somethings actually think they are a Japanese car.

But if you were a kid in the mid to late '60s, you probably know about them. You probably still love the body style, sporty and sleek. They are just cool looking. Even if you have never seen one, you will probably agree when you do. Even today's tweenies (10-14 years) love them, especially the convertible!

Corvairs are known as the "poor man's" collectible car. They usually range from $1000 to $6000, over 2 million were made. Most are either on craigslist or eBay.

Parts for restoration are not an issue at all. Several places on the East and West Coast sell only Corvair parts. There are plenty of books about them. There are probably still over 40,000 of them in the US.

Owning a Corvair is an experience. It usually is a love/hate relationship. You love the car when it's running great and looking good, then hate it when you buy a costly part and are unable to install it because of rust.

The car is a time machine (well, any old car is) in that it makes one realize how far technology has come in 40+ years. Until you sit and drive one, it is hard to appreciate all the obvious and subtle differences. As a kid, I thought the '60s cars were sophisticated machines. They were for their time, but driving cars made since the '90s compared to driving a Corvair is like night and day.

The most noticeable differences involve metal: the nearly all-metal dash, the thicker body metal, more chrome. More strength is needed to steer the older car. With older cars, you hear more engine noise. Even though Corvair was Chevy's economy car, it's not small; it is as big as many of today’s cars!

The Corvair is low to the ground and comes with either two or four carbs that need to be synchronized in airflow and idle\fuel mix. The engines are primitive and simple, by today's standards, yet temperamental. Settings must be close to specifications, or they will not run correctly. A Corvair owner should always carry some tools and a spare fan belt, as one minute it runs perfectly, and the next minute it doesn’t.

A 1965 convertible in almost new condition with 47K, bought for $3700

A 1965 convertible in almost new condition with 47K, bought for $3700

The Corvair as a Collectible

Those who own a Corvair have a unique American car, the only rear-engine air-cooled American car ever made. Most buy them because they were exposed to them in the '60s when they were kids. Others buy them thinking they are a real “money maker” like a Corvette or Mustang. Not so. The Corvair is the “poor man’s” collectible car. Why?

The Corvair will seldom bring in as much as the 'Vette or Mustang in the same primo condition. The car suffered from a bad public image for a variety of reasons: it was called temperamental, an oil leaker, unsafe (thanks to Ralph Nader), and, in its pre-1965 models, ugly.

Owning such a car is usually reserved for the mechanically inclined or rich guys who can hire someone. In either case, you will need to find and purchase the manuals for your car's year, model, and chassis. These will help you repair and diagnose the inevitable problems. Without manuals, you are lost. Even with them you may be! If you don’t already have them, you will be investing in more tools. If you are not a mechanic by nature, you will become one just to save money and time. And if you are a mechanic, you will need the shop manuals, as the Corvair is not a typical GM car!

The problem with nearly all previously published material is that it presumes the target audience is either a mechanic, was a hobby mechanic, or knows a lot about '60s-era cars. Even mechanics who know your standard type engine, knows little about the Corvair engine, unless they worked on VW’s, its closest cousin!

I have the manuals and books from the “pro” owners, but many times the procedure was lacking in detail for a newbie, because the target audience was presumed to know general items related to the field. This led the writer to gloss over details instead of creating a detailed procedure.

For any new Corvair owner, the most helpful resource is This is a forum for only Corvair owners with none or years of experience. Their advice and tolerance helped me a zillion times. You can post a question, and within hours someone will provide the answer.

Read books on Corvairs, mainly those by Bob Helt and Richard Finch as well as the GM manuals. They all have their role. As a novice, all of those books did help me, but all were lacking in some way, and all were written for those who were much more experienced with cars in general.

The original 1954 Corvair prototype based on the Corvette

The original 1954 Corvair prototype based on the Corvette

A Brief History of the Corvair

The Corvair name originally belonged to a fastback show car in 1954. Like many Chevy concept cars of the period, it was based on the Corvette. The design was an answer to the growing popularity of small, lightweight imported cars (namely VW).

The car was originally an experimental two-passenger fastback and was a “new aerodynamic design” for the sports car class. The streamlined roofline swept back into the jet exhaust-type rear opening. GM failed to convince the public, and sluggish sales of the 1954 production model Corvette deterred GM from moving forward with the 1954 fastback coupe.

Of course, the nameplate would be recycled later for the infamous 1960 rear-engined compact car. This version was a rear-engine vehicle in the style of the Volkswagen Beetle and the Porsche 356 Speedster and shared very little with the 1954 concept but for its name.

The rear engine version design began in 1956. The early model (EM) style is a more boxy, dated body style, while the later model (LM) from 1965-69, is a timeless design that continues to appeal due to its sporty corvette type look and a European sports car.

A dramatic redesign of the Corvair body and suspension and several powerful new engines came in 1965. A new fully-independent suspension similar to that used on the Corvette replaced the original swing-axle rear suspension. In 1966, one change of note was a more robust four-speed synchromesh transmission using the standard Saginaw gear set used by other GM vehicles. In 1967, the 140 hp and 180 hp engine options were deleted as well, although the 140 hp option would remain available until Corvair production ended in 1969. Dual brake system was also introduced allowing for independent braking.

Corvair production finally ceased in 1969 with sales of only 6,000 cars, a victim of Nader's book, and also of Ford's Mustang, and Chevrolet's own Camaro and Nova, and other mid-60’s muscle cars, all having way more horsepower. Oddly enough, despite its sporting look, it was never intended to be a muscle car with high HP. It was always an economy car even to the end. Chevrolet did provide “muscle” car type packages, such as a 180 Hp Turbo and a four-carburetor 140 hp, but even these additions were weak in power when compared to a stock Mustang with a 289 hp.

A new Corvair in 1965-69 ranged from $2000-3000. The top of the line was the Corsa. Corsa’s were only made in 1965 and 1966. Why? Corsa failed because the difference between it and the less expensive Monza was small: a Corsa had more gauges on the dash giving it a racing look, the trim and emblems were slightly different, and the engine was a 140 hp or more, but apart from those features, one could not tell the two apart. So if you have bought a Corsa, make sure by its VIN that it is really a Corsa, not a Monza made to look like a Corsa! To complicate things, you could buy a Monza or the most base model, the 500, with a 140 hp motor, and except for the trim, little else was different.

The Corvair was radical for an American car, and litigation and controversy followed it throughout its life. One main issue that continues today are the pushrod rubber O-rings. During its production, the material to seal the tubes into the block and head was unable to withstand the high engine temperatures, and after about a year, the car would begin to leak oil. The leak would only get worse over time. Once the oil leaked onto the hot exhaust, the burnt oil smell permeated into the interior at times or could be seen while at a stop light or when the car stopped coming from the vents.

Also, carbon monoxide could also enter the passenger compartment if the engine hoses connected to the heater had become disconnected or fallen apart. I recall this vividly as my friend in high school had a Corvair and picked me up in the morning. In the dead of winter, we drove with the heater on and windows open to avoid being asphyxiated! It was not until the 70’s that a new O-ring was created for other uses. This Viton O-ring, once installed correctly would create a leak-free Corvair as the rubber O-rings could withstand high engine temperatures without falling apart.

Enter Ralph Nader

This young lawyer nearly destroyed the car with his book, Unsafe at Any Speed. In his book, only one chapter specifically mentions Corvair issues and only with those made from 1960-64. The rest of the book deals with car manufacturers in general and why safety was really a political issue.

One of his gripes was that the steering column, upon impact, would be shoved into the driver causing serious injury. Not many cars at that time had collapsible steering columns.

His more serious accusation was its steering. A driver could easily oversteer and flip the car over because it only weighed 2000 lbs. This was true if the tire pressure in the front was 25-35 psi; however, Chevy knew this and stated clearly the front tires should not exceed 15 psi, though your typical buyer did not heed the warning.

The car was designed to avoid terminal oversteer by using very low air pressure in the front tires, typically 12 to 15 psi , so that they would begin to understeer (slip) before the swing axle oversteer would come into play. Although this pressure was quite adequate for the very lightweight Corvair front end, owners and mechanics, either through ignorance of the necessity for this pressure differential between front and rear or thinking that the pressure was too low for the front, would inflate the front tires to more "normal" pressures (25-35psi), thus ensuring that the rear of the car would lose traction before the front, causing it to oversteer.

It should be mentioned that the Corvair is by no means unique in requiring different front and rear tire pressures for normal controllability. The Ford Explorer (many years later) had widely-publicized stability problems when equal pressures were used. See Firestone vs, Ford Motor Company controversy. Corvairs built from 1965-69 do not have this issue. Chevy had made the necessary changes to the chassis as a result of his book.

Nader overstated the severity of the handling problems, as was later found by US National Highway Traffic Safety Administration investigators, and Chevrolet made changes to the suspension: in 1964, adding a transverse leaf spring extending between the rear wheels to limit rear wheel camber change. In 1965 the Corvair got a fully independent rear suspension closely resembling that of the Corvette, even sharing some components.

The National Highway Traffic Safety Administration (NHTSA) ran a series of comparative tests in 1971, studying the handling of the 1963 Corvair against four contemporary cars: a Ford Falcon, Plymouth Valiant, Volkswagen Beetle, and a Renault Dauphine. A 1967 Corvair (with a revised suspension design) was included for comparison. The final result concluded, "The 1960-63 Corvair compares favorably with contemporary vehicles used in the tests...the handling and stability performance of the 1960-63 Corvair does not result in an abnormal potential for loss of control or rollover, and it is at least as good as the performance of some contemporary vehicles both foreign and domestic."

Nader is wrongly vilified for the demise of the car. While his book did not help, the muscle car fad of 1964-71 was what really killed the Corvair. From 65 on, the muscle car fad was just in full swing. While the LM Corvairs looked great and their style has withstood the test of time, they were never muscle cars. So, their racy look was misleading to all as they only had either 140 HP or 110 HP. When compared to other cars, it was underpowered, to wit: the 289 HP Ford Mustang in 1964, the Hemi engines of Dodge and Chrysler, the GTO and Le Mans from Pontiac, even Chevy had the Malibu SS, Corvette, Camaro. To combat this, the Corvair could be bought with a 180 HP, which was still way under the others.

The car was king for gas economy, averaging 20 mph or so; unfortunately, this feature was ill-timed. With gas only 25-50 cents a gallon until 1971, nobody cared, which favored the gas-guzzling muscle cars. Had the Corvair lasted until 1973-4, when the oil embargo occurred and fuel economy was important, the car might have survived.

General Motors produced nearly 1.8 million Corvairs over 10 model years. The Corvair pioneered such technological advances as turbo-charging, true four-wheel independent suspension and unit-body (or unibody) construction, and its independent suspension was adapted for later model Corvettes.

Today, 41 years after its introduction and 30 years after production ceased, the Corvair still enjoys a loyal following. The Corvair Society of America (CORSA) has a membership of over 5,500 people with 130 local chapters found everywhere from Idaho to Amsterdam. There are probably over 20,000 of them on the road. Some owners have several. Parts are easy to find from Clarks, Corvair Underground, and Larry’s.

Corvair Design Nuances

Engineers at Chevrolet began designing the rear engine Corvair in 1955 or 56 by investigating the foreign cars being imported into the US at that time, namely VW, Opel, Fiat, etc. After considering all the pros and cons of each, it was decided to create an entirely American rear air-cooled engine car, as none of the foreign cars were satisfactory. Chevrolet also considered a front engine car but quickly came to the conclusion this was not the way to go. Early on, it was decided the car would have an aluminum engine to reduce weight and more importantly, a 40 front\60 rear percentage weight ratio for its stability platform. This weight ratio would allow for responsive steering, fairly uniform braking wear, and better traction. Early on, performance was also clearly defined with a target of 0-60 mph in 20 seconds and a constant fuel economy at 50 mph of 25 mpg. This is still a good economy in 2008! To achieve these goals, engineers focused on making the car light.

Using an IBM 704 computer, (yes, computer!) engineers entered over 300 different types of cars over a four year period, both American and foreign. Weight ran from 5000 lbs (American luxury cars) to 2000 lb. foreign four passenger cars. In the end, the computer model designated a 3000 lb test weight (curb weight of 2400 lbs, with 600 lb payload). To compare, the Corvair weighed 2382 lbs in 1960, versus a Chevy Biscayne at 3714 lbs., a difference of 1,332 lbs!

The IBM 704 used highly advanced fixed-point or floating-point arithmetic for the first large-scale produced computer. Both of these modes of operation are completely automatic. It was available from 1954 to 1960. The computer multiplied or divided in 240 microseconds, or approximately 4,000 operations per second. The doubling of speed in arithmetic, plus the use of index commands, made the 704 a very versatile and capable data processing machine for its time. Its principal language was FORTRAN. The 704 was considered a “super-computer”.

An individual magnetic core was about the size of a pinhead and was shaped like a doughnut -- with a hole in the center. In a 704, thousands of cores were strung on a complex of wires in such a fashion that several wires passed through the center of each core. Combinations of electrical pulses on these wires altered the magnetic state of the tiny cores, and a line of cores, some altered, some unaltered, stood for a certain word or number. A word or number stored in the magnetic core memory in this fashion was available for calculation in 12 millionths of a second.

In addition to this high-speed memory, the 704 had a magnetic drum storage unit. The drum could be used for storage of parts of the program, intermediate results, rate tables, or other information. Finally, the tapes themselves acted as bulk storage, each holding up to 5 million characters.

The usual method of input to the system was magnetic tape, but entry could also be gained from punched cards through the card reader or from the operator's console, if special instructions were required. All information, whether part of the data to be processed or part of the program of instructions, started out on punched cards. Then, it either could be converted directly to magnetic tape before being read into the system, or it could be read directly.

Once established, the IBM 704 computer was used again to determine the correct engine to build for such a car. Again, over 300 were entered, and data was retrieved. The computer indicated the correct match would be a 140 cubic inch motor and 13” wheels.

Chevy wanted the Corvair to have a smooth ride similar to its larger cars. To do so, they used independent coil suspension and efficient swing axle with coil springs. The swing axle proved to have far less wheel hop and shake compared to rear axle cars. Coil springs on all four wheels also smoothed out the ride. The swing axle also proved to have excellent roll stability.

The combination of understeer built into the front and rear suspension, small wheels, proper tire inflation, and low to the ground made the Corvair one of Chevy’s best-handling cars. It was found that when the car’s tires were properly inflated, 15 psi in front, 26 psi in rear, the car handled better around corners than cars with larger tires and was a very stable platform. Sadly, while the car was stable if the tires were correctly inflated, it was not (front wheels would lose traction) if the tires were inflated to what would seem the “normal” range, that is, 26 psi all around.

This nuance remains critical to owners of 1960-64, and one that Ralph Nader homed in on. Chevy’s only fault was that they did not emphasize how important proper inflation was to the new car owner and old habits are difficult to break for the general public. From 1965-69, the problem was no longer there as Chevy had made changes to those models, yet, they still recommended to properly inflate.

Engineers early on demanded that the car would have front and rear independent suspension in a unitized format for handling and rideability. The rear suspension geometry of the car made for anti-lift during braking and in the front, anti-dive in the front. That is, when the car brakes, it basically stays flat, unlike all other cars. Its swing rear axle reduced wheel hop. The placement of the fuel tank in the front between the front cross member and passenger compartment nearly made it impossible for it to be impacted upon collision from the rear, front or side. Having it at the other end of the car made it totally removed from the exhaust in the rear — no chance for ignition.

Because of the car’s balanced design, brake wear remains very little. In Chevy tests, the average wear on the brakes after a 1000 mile test was only .004”.

Corvair’s luggage capacity was also significant for a small car, with the rear seat folded down, the rear area had 17.6 cubic feet, and the front trunk, 11.3 cubic feet.

140 hp 4-carb engine

140 hp 4-carb engine

Chevy had decided early on to go with an aluminum engine to reduce the car weight. One early engine design had the engine heads and cylinders cast into single pieces, each consisting of three cylinders, a head, and intake manifold. This idea was discarded since special coatings would be required which was beyond that era’s technology. Thus, while most of the Corvair engine is aluminum, the cylinders are cast in iron, adding another 12 lbs. to the engine.

The air flow of the engine is such as the air is not sucked in through the air filter, but is pushed out from the carburators and through the filter, totally reverse from most other cars.

One item of concern for the engineers was the engine design and its ability to deflect heat. It was decided to use the air fins so commonly found in aircraft engines to channel and deflect heat and air. Engineers found out that within the engine compartment, 18 cubic feet of air per minute per horsepower. During engine destructive testing, tests showed that the Corvair engine could withstand temperatures of up to 600°F without serious damage. The air passing over the engine came to 60% over the cylinder heads and 40% over the barrels. These requirements demanded that the Corvair blower consist of 24 vanes, producing 1850 cubic feet of air per minute at 4000 rpm.

The fan belt is one notable feature of the Corvair engine as it turns and twists a total of 540 degrees. As designed, the belt is to last 250 hrs at 4000 rpm. It was also found out (despite folklore) that the car can be driven at slow speed for a limited time without the belt.

The oil cooler also plays a vital role as air moves through the fins keeping the oil temp to 280 F when at full throttle, at an ambient temperature of 100F. In cold weather or when the engine is started the cooler is bypassed, and oil is sent directly to the oil galleries. The bellows thermostat below the left cylinder bank has a temperature range of 185-195F, at which time discharge occurs and the door vents open. During winter months, the thermostat keeps the engine ambient temperature at 80F.

Engine temperatures range from 300°F at 20 mph to 445F at maximum speed (100 mph). It operates at its lightest load when in idle and in heavy traffic since the blower is regulated by the engine speed, not the load. When climbing long hills or mountains, the engine temperatures rises only 20-30°F higher than its maximum speed on a flat road. The aluminum in the engine weighs only 92 lbs, or 28% of the total car weight. The total weight of the engine is 256 lbs, which was half of the normal Chevy car at the time.

The '65 and '67

The '65 and '67

A Checklist for Buying a Corvair

There are some universal items one should check into or look at if (if possible) when buying a Corvair. Many of the issues can be asked of any car-it is not rocket science. If you cannot personally inspect the car or have a proxy do it, be sure to ask the correct questions.

As a buyer, you must investigate and interrogate the seller. Failure to do this may yield a ca you should not have bought. If you do not get satisfactory answers, ask again, if no answer comes back or only half an answer, that is a red flag. Do some research or talk to other owners and prepare a series of questions that will reveal the condition. Focus on the chassis and engine first, then the interior.

As a newbie to Corvairs, make life easier—buy only a car that runs and has brakes. Buying a car you cannot drive poses all sorts of question marks and unknowns—some think this is fun—I don’t. I consider it a red flag about the true internal condition despite the excellent body and external appearance. There is a reason the car does not run or has no brakes- and it probably is bad and costly!

Having bought both of my Corvairs online- you must have trust and faith in the seller. If there is any doubt of being ripped off, not getting the truth, don’t deal with the seller. Period.

I was going to buy a LM Corvair on eBay. During the auction I asked specific questions that would reveal the car’s condition. Some were answered, most were not. I was suspicious. In the end, I won. I asked the same questions after and this time answers revealed a very rusty chassis, ripped seats under the covers, brakes not working. I refused to pay and Ebay eventually allowed me to withdraw my bid and chastised the seller for non-disclosure of material facts. Facts, had I known about, would have made me not bid for the car. One tip-off regarding the rust was that when I demanded the car at least have some braking capability, the owner acquiesced and tried for three hrs to remove a bleeder nut on the front wheel. When he reported back to me, I knew the chassis was probably quite rusty.

Some Corvairs look like new cars externally, yet their chassis is so rusted (snow, salt or rain) its safety and structure is compromised making it dangerous.

A couple of key questions can reveal the state of the engine, depending on the answer. You can always ask for a video file to listen to the engine. You want to hear a steady engine with minimum clicking or tapping, steady hum and one that is near vibration free (the coil should not be moving very much). If there is excessive vibration, this may indicate bad engine mounts or engine balance.

Here are a few key questions:

  1. Does the car stall at stop signs or lights? If yes, it indicates that the carbs are not synchronized and the idle and fuel\mix screws on both carbs are not at the correct setting (both must be near identical settings). Timing may also be off. A vacuum leak, clogged carb jets or filters are key suspects. Not a big deal when you learn how to do it.
  2. Does it idle steady? If no, same as #1.
  3. Does it hesitate on acceleration from a stop? See #1.
  4. Does the car leak oil after the engine has been running for 15-20 minutes and turned off? If yes, it indicates that the O-rings, valve cover gasket, and/or oil cooler seal may be defective. Most likely suspects are the O-rings that fit onto each end of the Push Rod Tube. Even if the leak is bad, once these are changed, the leak will be gone, unless other gaskets etc. leak. Again, once you do this yourself, it is not too forbidding. The car does have to be hot (15 min running) and turned off to determine. Running it less than 15 min, does not get the engine hot enough.
  5. When the car brakes, are there any scraping or squealing noises? If yes, probably needs new brake shoes or relined drums.
  6. When braking, is the brake pedal spongy or near the floor when the car stops? If yes, indicates air in the brake line or leak at the master cylinder or at the brake lines. A car that needs no brakes will be silent, and the pedal will NOT go near the floor, very little foot pressure is required to stop. If there are no brakes in the car, both 5 and 6 are the reason. Also, ask if the master cylinder or wheel cylinders leak brake fluid.
  7. Does the Automatic Tranny Stick read (when car is running and hot) empty or very little? This indicates either that the tranny needs ATF fluid added OR a defective modulator on the tranny. The Corvair TTF level is checked when the engine is hot and running, if the reading is nil, something is wrong. It should read something on the stick. Changing the modulator is easy with the correct tools.
  8. Does the car shift easily? If an automatic, the shifting is usually between 10-30Mph, if a stick, if it does not go into gear, may be a clutch or something else.
  9. Do the instrument gauges work on the dash? If the fuel gauge does not, it is the fuel sending unit in the gas tank. Either it needs to be replaced, or the ground wire that attaches to the car frame is gone\disconnected. Again, not a hard thing to fix. If the car blinkers do not work, it is probably the turning switch inside the steering column. If the blinker arm works properly, yet no blinkers, may be the bulbs or a new Flasher unit needs to be installed or other troublesome electrical issues.
  10. Do the lights and wipers work? If the lights do not work, either the bulbs\connectors are bad, or wiring is bad. If wipers, the wiper motor needs to be replaced.
  11. Does the radio work? If no, replace the radio, check the speaker, which may be bad, check for antenna connection.
  12. Does the car have problems starting? Maybe be the Starter that is going bad, car may need a tune-up, fuel pump may not be good.
  13. Is the chassis and frame free from destructive rust? This rust crumbles the metal, creates holes, cannot withstand pressure. Surface rust does not; it has not done any damage yet, just discoloration.
  14. Are there rust holes on the floor of the car or car body? If yes, this is a nuisance issue if the car runs fine, but the floor will have to be replaced with new sheet metal, it can get very expensive.
  15. Does the car ride bouncy? If yes, indicates that shock absorbers and\or wheel coils need replacing. Not a big deal.
  16. Does the car have white or bluish smoke when running? If yes, the white smoke may indicate that ATF is getting into the transaxle because of a bad modulator, while bluish may indicate that the engine needs new rings around the piston.
  17. Is there an oil leak from the bell housing area? If yes, rethink about buying it as the engine must be removed to replace the seal.
  18. Any leaks from the tranny area? If yes, you may have to remove the tranny to repair.

I call these my core questions to assess the car if I am buying from a remote location. Besides these, I ask the basic common ones regarding previous owner, mileage, how it drives, paint condition, issues that are critical for operation and non-critical ones, how long the car has been not running, why?, when it ran last, when the car was bought, what has the owner done to the car, last time oil was changed or tune-up.

If I can get contact info about the previous owners, I try to contact them to their history of the car when they owned it; good info may be provided.

Naturally, car inspection is always best because opinions differ. If you are unable to, buying the car on the internet whether from eBay or Craigslist is totally doable and simply requires an act of faith and more questions than if you could not look at the car yourself. Requiring the seller to send detailed photos or video is common and if they cannot, be a little more cautious.

As a rule, if the seller does not provide details about the car and provide photos in his online ad, I am skeptical. These types of sellers are more likely just wanting to sell and could care less about the answers they provide. The whole purpose of the ad is to sell. If the seller responds to questions with non-direct answers or just short, curt ones, look elsewhere or confront the seller with the issue.

1966 Corsa Interior

1966 Corsa Interior

Why You Should Care About Rust

Rust is any old car’s number-one enemy. It can make a simple job turn into a costly, long, nightmarish episode. Any Corvair you buy will have at best, just surface rust. Even surface rust can cause problems. At worst, a Corvair can have such heavy rust as to make the car’s chassis unsafe and an externally nice-looking car worthless. Rust multiplies everything: your time, cost to remove, cost to fix things, and so on.

Most Corvairs one can buy fall in between the extremes of the rust range depending on where the car spent most of its life. If it spent its life on the East Coast, with the winter snow and salt, the car will have serious rust. How bad depends on whether the car was kept in a protected area. If the car was in the Midwest, the same applies, but may be not as bad. Corvairs that spent their life in the South, Southwest, or West generally have the least rust.

In a nutshell, you want the least amount of rust. Rust destroys. It creates holes in the body, brings restoration to a halt (even the most minor things like getting a nut off), forces you to spend more money, causes frustration. You will have enough frustrations without additional rust-caused ones.

Dealing With Your Rusting Car

Rust is oxidation, which occurs when oxygen comes in long-term contact with certain metals. Over time, the oxygen combines with the metal forming a new compound called an oxide and weakening the bonds of the metal itself. If the metal is iron or steel, the rust is properly called iron oxide. Rusted aluminum would be called aluminum oxide, copper forms copper oxide and so on.

The rusting process is water. Iron or steel structures may appear solid, but water molecules can easily penetrate the microscopic pits and cracks in any exposed metal. The hydrogen and water can combine with other elements to form acids, which will eventually cause more metal to be exposed. If salt is present, corrosion will likely occur more quickly. Meanwhile, oxygen combines with metal to form the destructive oxide compound. As this happens over time, they weaken the metal, making the structure brittle and crumbly.

Some pieces of iron or steel are thick enough to maintain their integrity even if rust forms on the surface. Others are protected by water-resistant paints or other chemical barriers such as oil, dirt caked on with oil over time. The thinner the metal, the better chance rusting will occur. Water alone does not cause steel to rust, but the acidic reaction allows oxygen to attack vulnerable exposed metal. For example, placing a steel wool pad in water and exposing it to air will cause almost-immediate rusting. Rust formation is a cancer that cannot be stopped easily, but metals can be treated to resist the most damaging effects.

Rust translates your Corvair into an expensive mess. It is on every Corvair-somewhere. Cars that lived in the Midwest or East will be in far worse shape than a car from the South, Southwest, or West. If you have long periods of snow and salted roads, it will eat any car over time. Areas with only rain will fare much better.

Rust will halt your restoration process and make it more expensive at every turn. It will halt the process with a simple rusted bolt holding a brake line. Soaking it in Liquid Wrench and tapping and banging can usually help get it off. Sometimes, it may take 45 minutes of soaking and banging until it is freed. The worst-case scenario is that you have to cut if off. Rust is your enemy so try to minimize the war by buying a car with the least amount! If you see the rust is heavy on the chassis and floor, think about the problems it will cause even if the body and interior are mint. Think about how you can remove it. I would rather buy one that looks so-so and have it near rust free.

If rust is showing up on the body of your vehicle, you may want to engage in some simple rust removal and color blending in order to maintain the appearance of your car. There are ways that you can do the job yourself, although it will take several steps and a couple of days to accomplish. If you have a free weekend coming up, here are the basic steps involved in removing rust from a car.

Rusting normally occurs because the finish has been damaged in some manner. The rust spot increases as oxidation on the bare metal that is exposed by a hairline scratch or a small dent causes the rust to spread. A sanding wheel along with a few sheets of sandpaper will also come in handy. Finally, have a small amount of rust acid compound on hand.

Begin by covering and taping off the area surrounding the scratch or dent. The idea is to protect the immediate surface that is still in great shape. Roll up the windows on the vehicle. When you begin to sand the rusted area, tiny particles will fly in every direction. Make sure none of the fine rush particles have a chance to settle and begin to imbed themselves in other areas of the car body.

Your first task is to address the thicker outer layer of oxidized rust. Use the sanding wheel for this part of the job. Do not rush with this step, as moving too quickly makes it easier to cause damage to the metal. Once the tougher outer layer of rust is removed, switch to the sandpaper sheets to get into the fine nooks and crannies. This will help ensure you get all the rust from a car during this procedure, including any small amount or residue that may have resettled during the sanding action.

When the sanded surface feels smooth, gently wipe it clean and apply a thin coat of the acid to the area. This step will handle even the tiniest of particles and leave the exposed metal perfectly clean. Make sure to not leave the compound on the exposed metal longer than recommended in the instructions. Failure to remove the acid could lead to pitting and even more work. After removing the acid, gently wipe the area with mineral spirits and a clean cloth, and allow the section to dry.

Keep in mind that removing rust from a car should only be done when you can re-prime and repaint the sanded area within the next twenty four-hour period. If you choose to leave the bare metal exposed for even a short time, the process of oxidation will take place and the damage will be worse than the initial problem. When you prime the car, remember that primer is not paint and does not repel paint. Protect the car if it is sitting outside in the elements. If you prime the car and it starts to develop surface rust, you will have to sand it again down to metal and prime again!

Common Home Remedies

Cream of tartar, hydrogen peroxide, and a product such as Borax or baking soda can be combined to create a homemade rust remover paste. The Borax or baking soda can be replaced with other similar products because their main purpose is to add grit to the solution without causing damage to the surface when used. To make this rust remover, a teaspoon of cream of tarter and a quarter cup of Borax or baking soda should be mixed with enough hydrogen peroxide to make a thick paste.

The paste should be rubbed onto the rust spot and allowed to stand for 30 minutes. Then, the rust stain should be wiped away with a damp sponge. If the stain remains, the entire process should be repeated.

White vinegar is another rust remover commonly found in homes. When using white vinegar as a rust remover, it should be sprayed directly onto the rust stain and scrubbed in. Then, the area should be sprayed again with white vinegar and allowed to sit for twenty to thirty minutes. After being allowed to sit, the rust stain should come off easily when the vinegar is wiped away.

66 Corsa

66 Corsa

Oil: Use Only CI-4\SL

It is strongly advised by most Corvair owners to use only CI-4/SL type oil in your car. The reason has to with the wear on flat tappet valve trains and other parts of these engines caused by the reduction of ZDDP in the newer oils (API SM and CJ-4). In the '60s, oil was different and more “primitive”. Today these base oils would be called “API group I”. This is the group you do not want in your car. The CI-4/SL type contains the correct amount of ZDDP, which is a combo of zine and phosphorus to protect and reduce wear on the engine parts!

ZDDP tries to adhere to the metallic surfaces of the engine to keep it clean or keep it from wearing during periods of contact. Very important! Using oil not labeled with this classification will work, but over time, your engine will deteriorate faster depending on driving habits and frequency. A good CI-4/SL (not SM) oil in the market today has 1200 to 1400 ppm of zinc and 1000 to1200 ppm of phosphorus.

Viscosity is thickness. The higher the viscosity, the higher the fuel consumption, engine temperature, and load on the engine. The Corvair Service Manuals recommend SAE 10W-30 or SAE 30 for most operating conditions anticipated. Chevrolet designed this engine to run on oil that is between 5W-30, 10-30, 30, 0-30, 10-40W.

Many people consider lifter noise normal. While a few seconds could be considered normal, any more than that is damaging the engine, especially on a Corvair engine that uses pushrods between the rockers and the lifters. The noise that you hear is the banging of metal, whether internal to the lifter or directly against the ends of the pushrods. Every “bang” adds up, causing more fatigue, wear and distortion of the ends of each piece. Even a sliding tappet has increased wear when it receives a hit in the middle of its slide.

Assuming the valves are properly adjusted, there should be no “play” in the system and the lifters or rocker arms should be silent. The causes of lifter noise are:

1. Actual mechanical damage in the camshaft lobe or the lifter itself.

2. Broken parts within the lifter.

Low-quality oil or excessively high metallic anti-wear additives (ZDDP) in the oil increase the deposits. Wax, sludge, or varnish deposits cause internal parts to stick. This is typical of an engine that sits for long periods (months to years) without use. The oil oxidizes where it is, forming varnish deposits. Running an engine too cold or many short trips without a longer/hotter trip weekly or so will also lead to sludge.

On a cold start the oil is much more thick than at other times, creating resistance to flow through the pickup screen and passageways. The thicker the oil, the slower it travels. So, 0W-30 or 40 travels through the engine fast, while 10W-30 is much slower, 15W-40 is the slowest. This is why one does NOT to race your engine at start up! Let it idle for at least one minute.

In general, a Group II oil will have better performance with 10% less additives than a Group I oil. So when you look at the container try to find at least a Group II. Group I oil is old technology, so to speak.

A Few of Many Sites for the Corvair

This article is accurate and true to the best of the author’s knowledge. Content is for informational or entertainment purposes only and does not substitute for personal counsel or professional advice in business, financial, legal, or technical matters.