Nicaragua's Sandinistas losing their followers; Even former guerrillas say their rulers fail to deliver

Nicaraguans are turning sour on the Sandinista revolution that overturned the Somoza regime in July 1979.

At least it is strikingly evident in this city, a short drive from Managua.

Dissatisfaction with the government - so obviously growing in this more traditionally conservative city - is also mirrored elsewhere in the country. Disillusionment crosses the political spectrum, represents all ages, and is seen in both elite and poor homes.

Over and over again, the visitor is asked if he is a North American, a gringo , or a Yankee, and once he says he is, the smiles of friendship broaden.

A sign on a wall says: ''Go home, Yankee.'' It is crossed out and reads: ''Come back, Yankee.''

One may read too much into these vignettes, but there can be no mistaking the developing disgust with the Sandinista leadership.

''We've been deceived by the Sandinistas,'' comments a young man in the shaded coolness of Granada's large, tree-filled central plaza. ''They came to power promising relief from the oppressions of Somoza, but life is not better today,'' he added.

This young man, who with his brothers joined the Sandinista guerrillas' final offensives against Gen. Anastasio Somoza Debayle and his National Guard, is obviously disillusioned by what has taken place since the Sandinistas triumphed more than 21/2 years ago.

Today he works as a carpenter - ''but there is little work, except to build monuments to the Sandinistas.''

Behind this obviously cynical attitude lies the fierce independence of Nicaraguans who no more like the regimentation of the Marxist-leaning Sandinista government, and the atmosphere it spawns, than they did the repression of the hated Somoza government.

''Ay, those Sandinistas have failed completely to deliver on the promises of the revolution,'' says an older voice from an open doorway. ''They have lost their way.''

One of the younger men, a grocery store owner, responded: ''No, Juan, they have not lost their way; they know what they are doing, but they have no experience. What they have is an ideology and a determination to get their way.'' Despite these dissatisfactions there are no indications as yet that the country is about to throw out the Sandinistas.

Yet all around this city, and indeed in just about every part of this Central American country, that answer ''we don't have it'' is a common phrase.

In a nearby grocery store whose shelves were much barer than they had been on this reporter's last visit, a woman complained because there was no sugar.

It was a similiar shortage of staples that prompted Granadans and other Nicaraguans in the late 1970s to blame General Somoza, eventually a factor in the massive nationwide movement to oust him.

One overriding reason a similar movement would not dislodge the Sandinistas is the Army: It is firmly in control. Another persuasive reason is that the Sandinistas do get some good marks for their work in such activities as broadening educational opportunities and cutting back sharply on illiteracy.

Yet the Marxist ideological orientation of the Sandinista government is deeply disturbing to many here. And there is little doubt that the Sandinistas' nearly three-year-old government is much less popular today than it was when, as guerrillas, the Sandinistas took over in July 1979 from General Somoza.