Baltimore Mayor William Donald Schaefer ventured out of his cash-strapped city last night to bestow an expensive favor on Montgomery County -- a promise to lend city road engineers to help the state's wealthiest jurisdiction with its worsening highway problems.

Schaefer, a Democrat, is widely seen as running for governor in 1986, and the trip was viewed by Montgomery politicians as one of those reversals that only gubernatorial politics can produce.

Schaefer made no mention of politics, but told members of Montgomery's House and Senate delegations, with whom he has frequently sparred on issues ranging from highways to education: "The consensus is that when you come from a subdivision like ours where we are not as wealthy as you, that we're always takers. I don't want to be a taker. I want to be a taker and a giver."

The mayor told county officials he would lend as many as four city highway planners to help Montgomery expedite the planned widening of I-270 in the upper county.

State transportation officials recently told the county that a shortage of highway engineers threatened to delay the widening of I-270 until after 1989, when construction is scheduled to begin on adding two high-speed lanes and four access lanes to a 16-mile stretch of the road.

County officials say the $125-million project to widen the six-lane highway is the single most important road improvement necessary to spur high-technology development and ease the the daily traffic jams on Montgomery's major north-south commuter route.

Today's stop followed similar trips to the Eastern Shore and Western Maryland by Schaefer.

County legislative leaders made a point of meeting with Schaefer at the Washingtonian Country Club, just a few yards from I-270, at 5 p.m. yesterday, in hopes that Schaefer would experience first-hand the travails of driving on the interstate at the beginning of the evening rush hour.

Remarkably, Schaefer met with virtually no delays on his trip to the country club, arriving only three minutes late in his gleaming, blue Buick Electra.

But the fact that he met with no traffic jams did not stop the Schaefer's wit from drawing attention to Montgomery's transit woes.

Said Schaefer, "You say that this is the worst traffic jam you've ever been in?"

Then, without missing a beat, the mayor added, "The only place I've seen less traffic is in Japan. In Japan, they have traffic running out of their ears."

The good will shown by Schaefer vanished only momentarily when he was asked whether he would support all or part of Montgomery's recent request for $40 million in special state bonds to build feeder highways to I-270 and construct new schools in the rapidly growing up-county area near the country club.

"I'm going to have to think about that, said Schaefer. "I support bond issues for Baltimore City, I support bond issues for counties. The question is priorities."

When asked again whether he would support Montgomery's request, Schaefer responded, "The answer is, I've said all I'm going to say."

Montgomery County officials said they were pleased by Schaefer's promised loan of several highway engineers. "I'm delighted," said Del. Ida Ruben, a Silver Spring Democrat who chairs the county's House delegation. "Whether he's playing Robin Hood, Montgomery County can't afford to question," Ruben said. "We need this project."

But state Sen. Howard Denis (R-Bethesda) was more sanguine about the mayor's visit. "This is our version of the SALT talks in Geneva," he said. "This is all about Schaefer and [how] he needs Montgomery County."