Because of recurring operational problems on the Metro subway's new Blue Line. Metro general manager Theodore Lutz is studying whether to recommend to the Metro board a delay in the major realignment of bus service that is scheduled for next Monday.

Metro plans to terminate or alter 210 bus routes on Monday to eliminate much parallel bus and rail service subway. Another major realignment of bus service - affecting 300 routes - in scheduled Sept. 4.

Both of those moves presume that the subway will be working. SInce the Blue Line opened from National Airport to RFK Stadium on July 1. It has been plagued with minor mechanical problems that have made riding the trains a frustrating experience. The trip from the Pentagon to Farragut West can take 8 minutes, as it supposed to, or 25 minutes, as it sometime does.

The biggest problem, a fiasco in Lutz's words, has been the automated fare-collecting system called Farecard. There are not enough Farecard vending machines or entrance and exist gates in most of the 24 subway stations and those that are there frequently do not work. Long lines of people are forming both to leave as well as to enter the subway system.

Lutz said in an interview yesterday that "we have to ask if we are going to turn off our riders" by forcing them to transfer form operating buses to balky trains.

To recommend a delay in the bus cutback, however, is to recommend losing more money, Lutz said that "we are thoroughly assessing" the question of whether subway service would improve enough during a bus cutback delay of two or four weeks to justify the less of subway revenue.

Metro has estimated that its bus cutback schedule will save it $5.3 million in operating costs in the fiscal year that began July 1, conincident with the opening of the Blue LINE.

The year's total operating deficit for bus and rail - $76 million - is supported in large part by property taxes from local jurisdictions and anything that increases that deficit becomes a political problem. Metro staff members were refining their numbers yesterday on what a two-week delay would cost in subway revenue. Metro board members have been insistent that buses be cut back at soon as possible.

Joseph Wholey, chairman of the Arlington County Board and vice chairman of the Metro board, has called parallel bus and subway service insanity and said in response to a reporter's question at least week's board meeting that "I believe the (subway) service would be sufficient . . . and don't anticipate seeking any delay in the switchover" from buses.

Lutx met with key Metro staff members yesterday and heard contlicting advice on what to recommend to the board at its next regular meeting Thursday, according to sources.

"The biggest problem." Lutz said. "Is the Farecard system. And we can't get much improvement there in two weeks."

Only two stations in the Matro system have all the Farecard equipment installed and tested - Pentagon and Rosslyn. Full equipment has been in stalled at National Airport and Rhode Island Avenue, but has not been tested.

"All stations should have their full complement of equipment by the end of the first week of November," said Paul Johnson, who is in charge of the Farecard program for Metro.

Every regular rider of Metro has least one Farecard tale: two vending machines broken in a station that has only two vending machines; long lines at the entrance and exit gates made longer while technicians fight with the machines; the machine making incorrect mathematical computations and charging one rider twice for one ride.

"We started July 1 with the minimum operational quantity of machines," Johnson said. "We just need more so that when one breaks down there is backup, and so that those we have get more rest."

The biggest problems are at Farecard West and McPherson Square - both new stations on the Blue Line. Only one of the two portals at each station is open, and there are only two Farecard exist gates.

Delays of 7 to 10 minutes to get out of Farragut West are not uncommon in the morning rush hour.

The problems with the trans are also ones of numbers. Monday morning, thousands of people (Metro will not say yet how many) from North Arlington and western Fairfax County will be forced from buses to the train at Rosslyn; many other bus commuters into the District from the south and east will find that their bus trips end at the Stadium-Armory or Potomac Avenue subway stops; virtually every Metro station in the District will be the terminus for some bus route that once went farther. Bus service still will be available for all those trips, but at less frequent intervals than today.

To handle those rowds of people, Anthony J. Stefanac, Metro's chief of rail operations, says he would like to have 13 or 14 six-car trains on the Blue Line. "With that, I could run trains every 6 minutes," he said.

Yesterday he was running the evening rush hour with three six-car trains and seven four-car trains.

In theory, Metro should be able to run with 106 operating cars. In the theory it has that many - in fact, it has accepted 180 acrs from the manufacturer, Rhor Industries.

Metro's train operations crew has certified only 150 of those 180, and 14 of those 150 are undergoing various modifications. That leaves 136, or 30 cars in reserve if Stefanac gets his 106.

Erich Vogel, Metro's chief of maintenance, said, "We do have some problems, but a lot of them we expected. We feel a car gets to be reasonable reliable only after about 20,000 miles - and we have not had these long enough to accumulate that kind of mileagc."

Some of the problems the cars have had are well-known of Metro riders; others are less visible. The most obvious is the sticking door. If the door does not seal, the train will not go.

Some passengers have figured that out and notice that if the light across the threshold is still on after the train signals "ding dong." that's the bad door. One man pushed the doors together yesterday after the train operator had tried three times to close them automatically. I worked, the train pulled out of Metro Center, and the man held up the victory sign.

There also are less visible problems with the safety devices that automatically adjust pressure to the loads on the train, and some motors have overheated because of overloading.

There have been three fires - one in the brake controls, one in the propulsion controls and, Monday night, an overheated motor.

The doors are being rechecked and readjusted; the brake device is being replaced. All this means that cars that should be available are not available. And as any rider knows, cars in the system do not always run properly.

Maintenance operatings on the Blue Line are also hampered by the fact that neither the Stadium nor the National Airport stations have maintenance facilities. Although Vogel has created makeshift maintenance facilities at the end of the Airport tracks. Major repairs mean that the car has to be shuttled through to the Red Line yards on a track under Farragut Square - a tedious process.

The good news is tha the cars are comfortable; the air-conditioning works; thousands of people are riding them: parking spaces around some Metro stations are harder and harder to find.

But, as Metro's irrespressible booster and official spokesman Cody Pfanstiehl said yesterday, "It isn-t working right. What we're having means that the impatience of the public and the media is growing."