Montgomery County auto mechanic Jim Iler has taken to packing a new item in his toolbox since the gasoline crisis hit Washington: a .38 caliber Smith and Wesson.

The weapon has become Iler's security blanket in dealing with what many Washington service station attendants says is the violence - and the threat of it - that accompanies the area's long gasoline lines.

A survey of 24 stations in the Washington area last week found only four where attendant's said they have avoided serious confrontations with customers since the shortage struck the area in mid-June.

Threats and verbal abuse have occurred daily, the attendants said. Onefourth of the stations surveyed told of customers threatening employes or of fistfights erupting at the pumps.

Some examples:

An angry customer smashed Shell station manager Derrick Franzier's ankle June 21, sending him to the hospital for two days. Frazier said the customer became angry when told the station, located in Prince George's County, was out of gasoline.

A cadillac driver pulled a machete on employes at a Hyattsville Exxon station and threatened to "cut your . . . a -- up" when told the pumps there were closed.

Two customers threw bricks into the window of a Gulf station in Anacostial last Sunday when the manager refused to sell gasoline during off hours. D.C. police have been summoned to that station 14 times to protect attendants since the crisis began.

Such problems have been widespread, police say. "There have been weapons displayed - handguns, shoulder weapons like a shotgun or rifle - (by) customers and employes," says an Arlington police supervisor, adding that between 10 and 15 percent of calls his departments has had in recent weeks have dealt with gasoline.

At one point, one out of every four calls to the Prince George's Police force to the Prince George's Police force dealt with gasoline-related complaints, a communications officer says. "The first couple of weeks. . . .it was bad," he says.

The violence often breaks out when motorists attempt to cut into lines. John Druhan, manager of a Silver Spring Amoco station, recalls that motorists wishing to preserve their spots in the line at his station cut one such fight short.

"The line started to move and everybody started honking their horns, so the two (fighters) got back in their cars and moved ahead," says Druhan. The motorists kept their places in line and the fight was never resumed, he says.

Verbal threats have become so frequent that few attendants say they bother to report them to police anymore.

"People get violent over this line thing," said Tillie Bell, manager of Gulf station at 1301 Kenilworth Ave., NE. "I've been told that when I leave (work) they'll watch my car, follow me and blow it up."

"It happens all the time - all day." Sunoco station owner Rudolph Pettaway said. "They say they'll blow up the station . . . It doesn't bother me that much. If they were serious they'd do it. . . ."

Dr. Gary Singleton, a Washington psychiatrist, says that there is good reason for the motorists to be frustrated. "When problems go on and on and there is no end in sight, people start to cave in," he said. "They lose control."

"Very few of the public want to understand," said a D.C. police officer. "They're desperate at this point."

Some attendants say the believe the tensions of motorists in the lines have eased in recent days. But several who say they are keeping weapons nearby or hiring security guards to police their lines say they are not police their lines say they are not ready to drop the extra precautions.

For their part, gasoline attendants say they are not immune to the frustrations of long lines either.

"If they give me a real hard time," says 6-foot, 260-pound Earl Sartaine, who works at a Hyattsville station, "I give it back to them. You really don't pay attention to them - unless they start pestering you. Then you tell them to shut up or you'll slap them upside the head."

Given the widespread tensions, station employes say they are concerned that the threats ultimately will materialize.

"You never win one [customer confrontation] - eventually you're going to lose," said Bruce Gaynor, who pumps gas at the Merit station at 6th Street NE, on Florida Avenue.

"If I get (somebody) mad enough . . . one of these guys is going to come back," he said. "I get paid . . . to pump gas - not to get hurt."