The economy is beginning to show signs that it's coming off the floor, and you can't blame President Reagan for trying to wring every possible political benefit out of that fact. Administration officials take the cream off every available statistic, and croon soothing assurances on the TV morning news shows.

In Manila recently, Treasury Secretary Donald T. Regan, while gracefully poking fun at his own wild guess over a year ago that the economy would come "roaring back" in the spring of 1982, nonetheless touted "one of the greatest bull market drives in recent stock-market history" as the forerunner of a solid, general recovery.

No one is disposed to argue with raw numbers: industrial production rose smartly in April, automobile sales have picked up from a miserable low, and mortgage rates in the 12-13 percent area have boosted home-building well over the numbers when mortgage rates were in the 16-17 percent area.

But a lot of questions remain in the minds of those who look beyond the next 12 to 18 months. In the immediate period ahead, there should be a further recovery, assuming that the recent increases in production will be followed by equivalent increases in consumer buying.

But can the recovery be sustained in the face of enormous budget deficits in the United States, and a potentially explosive Third World debt crisis that in its most benign form will slash American exports to the poorer nations, and in the most worrisome scenario could trigger defaults and a new banking crisis?

The harsh reality is that an adequate recovery--one that will cut into the 10 percent- plus jobless rate--can be achieved only if Congress and the president are serious about tackling $200 billion annual budget deficits, and if the world's leaders do something at the Williamsburg summit to deal with the combined growth-trade-debt problem.

The newly touted economic recovery may, at the same time, be both real and an illusion: factories operating at 71.1 percent of capacity in April are a better result than factories operating at 69.8 percent of capacity in March. That's real, and a boost for corporate profits. The illusion is that this number means very much for jobs.

Note what the hardheaded chief corporate executives said last weekend at their annual Hot Springs, Va., session with government officials: production is up, but laid-off employees will mostly stay laid off, thanks to robots and other forms of automation.

On CBS's "Face the Nation," Wall Street guru Henry Kaufman predicted that the spectacular decline of interest rates over the past year is just about over, which to him means that "the American economic recovery will continue in a kind of subnormal fashion." The kind of lift the American economy got as it surged out of recession in 1971, 1972, 1975 isn't in the cards.

And why not? It all comes back to the huge deficits, and it is both amusing and frustrating to hear President Reagan lambaste those "unacceptable" deficits, as if they are not largely the product of the original mix of Reaganomics.

Kaufman echoed the same kind of advice Reagan has been getting from Europeans, Wall Street analysts, and the Old Guard faithful in the Senate: plan for a recoupment of taxes given away two years ago in a way that will allow interest rates to go down some more.

"I think, really, we need much more of a dynamic policy in which there are compromises of significant order between fiscal and monetary policy," Kaufman said.

And how about that Third World debt "time bomb"? Last week in Paris, Regan himself cautiously warned foreign and finance ministers that potential "second-round difficulties cannot be ruled out." Used this way, "second round" is code language for one of two possibilities: still more countries on the verge of a default and requiring official bail-outs; or the need to give easier terms to those whose problems have already been "fixed" by a combination of IMF and commercial bank help.

How long can such a Band-Aid process go on? Not much longer, suggests Austrian banker and former Vice Chancellor Hannes Androsch. On a visit to Washington, he outlined the need for a "much longer-oriented" approach. He suggested that the IMF and other agencies refinance perhaps 10 percent of the existing $400 billion "in shaky credits" at lower interest rates and at longer maturities--now.

So long as the debt "time bomb" can explode at any time, it's doubtful that there will be more than a token economic recovery here or in Europe. As Androsch pointed out, the import curbs Brazil has already put into effect--trying to scrounge cash to pay the interest on its $90 billion debt--have cost 150,000 jobs at American exporting companies.