All I wanted was one of those gizmos with four wheels, a motor and a blade -- it mows the lawn. What I got is an engineering marvel, I suppose, and something of a pain in the grass.

Too much of my youth was spent pushing a balky muscle-powered reel lawnmower across acres of grass, so I was eager to cash in on the Sputnik generation's promise of the good life thanks to technology. What I didn't realize is that those futur shock stories are true.

Strolling into a hardware store and only prepared to tell a salesman how wide a swath I wanted my mower to cut, I was confronted by dozens of options, features and designs that made me feel as though I were shopping for a major weapons system. Here's a short list of choices facing yard lovers these days:

Two-cycle engines, four-cycle engines, single armature electric motors, double armature electrics, mulching deck, aluminum deck, steel deck, fiberglass deck, belt-drive, chain drive, direct drive, gear drive, points-and-condenser ignition, capacitive discharge ignition, splash lubrication system, pressure lubrication system, direct lubrication system, aluminum cylinder heads and blocks, cast-iron cylinder heads and blocks, aluminum and iron head and block aluminum and iron head and block combinations, twin blades, single blades, triple blades, rear baggers, side baggers, front bagger, electric starting, manual starting without spring loading, geared manual starting, rechargeable electrics, fingertip adjustable cutting height, bolt-adjustable cutting height, dry element air filters, oil-bath air filters, carburetor priming systems, deadman self-propelled controls, tow guards, trailing rock shields, chute deflectors, self-governing throttle controls, manual throttle controls, under-deck muffler discharge, above-deck muffler discharge . . .

Is this what we trained a generation of space-age engineers for? Complicated lawnmowers?

But there is more. On many mowers there is a small triangular label which reads, in part: "OPEI, model conforms to safety standards ANS."

OPEI stands for Outdoor Power Equipment Institute, Inc., a national trade association for manufacturers of lawn and garden equipment. OPEI has developed a set of safety tests, the passing of which entitles OPEI members to the little sticker. Here are a few of these tests:

The thrown object test -- 300 nails are introduced into the path of the mower blade and no more than 15 percent are permitted to strike a cardboard target eight feet away. No more than one percent may hit a target two feet above the ground.

The impact test -- a one-inch diameter steel rod is inserted into the path of the mower blade. No part of the mower is then permitted to hit a cardboard circle two feet away from the blade tip.

The unbalance test -- the blade has weight added or subtracted from one end and the test is considered a failure if, an OPEI spokesman says, "The mower flies apart in any way."

This sort of thing goes on for 70 pages in an American National Standard specification booklet, including sound level limits, blade-stopping time limits, warning labels that last the life of the mower, trailing shields, guarded power shafts, heat protection for hot contact points on the engine, gasoline splash shields around engines, etcetera.

But alas, despite OPEI's efforts to keep yard dummies from being ripped apart or burned by the good old American mower, it hasn't been enough for the Consumer Product Safety Commission. After Dec 31, 1981, CPSC will require mower manufacturers to provide devices that stop the blade from spinning within three seconds after an operator removes his or her hands from the handle. Which could add $50 to present prices, an OPEI spokesman says. t

So I suppose it's a good thing I got my mower this summer before things really get out of hand. What I finally ended up with sells for about $200 and is your basic four wheels, motor and a blade that spins around. But it does have these: an aluminum block and head, direct lubrication system, steel deck, under-deck exhaust, side bagging, pinion-gear "fingertip" pull starting, push-bulb priming, shorting switch, dry-element air filter, fuel shutoff valve, five-position instant cutting height adjustment, self-governing throttle, modular carburetor, trailing shield, chute deflector . . .

Of course, I still have to push it.