Story by Phil

The do it yourself guy would put in pure Prestone!… Pure antifreeze is like 10 weight motor oil, thick…Water pumps had a hard time pushing it.”

From 1961 thru 1963 Buick used the 215 all aluminum V-8. At the same time GM hooked up with a company called Dow Guard. Dow Guard made a product that was pre diluted antifreeze. Half water and half antifreeze in a quart can. They also produced a radiator cap that said “Use only 100% Dow Guard” Many a 215 left the assembly line this way. This lead people to believe the 215 used 100% antifreeze!

The do it yourself guy would put in pure Prestone! I believe it was around 1963 or 64 there was a legal problem with Dow Guard. Selling water in a can was not legal unless stated on container. So much for Dow Guard. We had many problems with the 215 because of this. Pure antifreeze is like 10 weight motor oil, thick. Water pumps had a hard time pushing it.

Also antifreeze gets corrosive with age. Average life is around 2 years weather you drive the car or not. Aluminum and old antifreeze don’t get along. Internal corrosion from inside the block would plug up the radiator. Most of the time you could not rod them out a recore was necessary. Overheating was a common problem with the 215. Not that it was a bad design but because the antifreeze wasn’t changed often enough. When an overheated 215 came in with blown head gaskets you held your breath when removing head bolts. Most of the time them threads in the block came out with the bolt. We had to retap the holes from 3/8 to ½ inch and use Pontiac head bolts.

This engine was put together with anti seze on most of the bolts that went into the aluminum casting. Most mechanics didn’t recoat the bolts on reassembly. This made it a lot of fun for the next guy. Thermostat housing bolts were a big problem because anti seze was not used.

The engine got an undeserved bad rap mostly because of the corrosion problems and overheating. With the proper maintenance it was a good little lightweight engine. We won’t mention the Dual Path 2 speed air-cooled transmission it was bolted to.

GM sold the engine to Land Rover and it is still being used today. The wrecking yards were cleaned out a few years back because people were converting them to a dry sump engine and using them in airplanes. I have seen several kit cars with them. Light in weight, high torque and good horsepower.


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