With Newport, Rhode Island, designated as her home port, Koelsch spent the rest of 1967 at Boston, Massachusetts, much of it in drydock, fitting-out, workmen covering the teardrop-shaped sonar dome with an experimental rubber coating; installing the Antisubmarine Warfare Ship Command and Control System (ASWC&CS); replacing eight superheater tube stubs on 1A boiler; and removing the Drone Antisubmarine Helicopter (DASH) equipment in preparation for the ship's receiving a manned helicopter capability.

All ships of the force anchored off Spithead, between Portsmouth (UK) and the Isle of Wright, on 14 May to be reviewed two days later by Queen Elizabeth II from the royal yacht HMY Britannia.

After a five-day visit at Cherbourg, France, the destroyer escort rejoined Wasp on 22 May to conduct Hunter-Killer Group (HuKGru) operations and to evaluate the installed Antisubmarine Warfare Tactical Data System (ASWTDS) west of Ireland.

The crew prepared their ship for a regular overhaul period by offloading ammunition at the Naval Weapons Station Earle, New Jersey, on 10 August and beginning a tender availability at Newport (21 August-14 September).

Reports of a Soviet submarine tender off Bahia de Nipe, Cuba, resulted in another interruption in her slate of training on 10 March, when she received orders to proceed immediately to those waters.

Following an upkeep period and type training in local waters, Koelsch got underway from Newport on 10 March 1972 for a six-week operation with the Spanish and Portuguese navies off the Iberian Peninsula.

Pausing at Palma on 2 September, the ship participated in a two-day NATO ASW operation prior to picking up a Navy Band at Barcelona to take part in a religious festival at Port Mahon, Minorca.

Arriving at Livorno, Italy, on 23 November for a five-day holiday port visit, the ship stopped at Toulon, France (29 November-5 December) before heading to Gibraltar for a turnover of operational orders.

Following a visit to the degaussing range at Charleston on 7 July, the ship conducted refresher training at Guantanamo Bay, and on 15 August joined other U.S. Navy vessels for CaribEx 1-76.

The ship departed Mayport on 14 April for a major deployment to the Mediterranean, spending her first two weeks with the United States Sixth Fleet participating in NATO ASW exercise Open Gate 76.

Koelsch steamed to a position southeast of Crete to stand by in alert status for Fluid Drive I, the first evacuation of American citizens from Beirut, Lebanon (19-21 June).

After celebrating the United States Bicentennial at Messina, Sicily, the frigate got underway on 7 July to participate in ASW exercises that lasted until she arrived at Kithera Strait, off Greece, on the 19th.

After two months of tender and restricted availabilities at Mayport, Koelsch participated in ASW exercises in the Narragansett Bay operational area off Rhode Island during the first week of June.

Sharem XXIII was used to gather raw data on submarine tracking for later analysis, and National Week was designed to evaluate tactical doctrine in a wartime scenario involving predominately U.S. ships.

Directed to unload all her ammunition at Naval Weapons Station, Yorktown, Va., Koelsch returned home on 15 March to begin preparations for her regularly scheduled overhaul (ROH).

After conducting sea trials in the Chesapeake Bay and Virginia capes operations areas, Koelsch ended her ROH and departed Baltimore, Maryland on 27 June 1979, onloaded ammunition at Naval Weapons Station Yorktown, and reached Mayport on 1 July.

Returning to Socotra Island, she conducted surveillance of a Soviet Navy ASW task group, followed by a transit to the Arabian Sea and a week of operations in the Straits of Hormuz.

The ship departed Mayport on 14 July to augment the UNITAS XXII battle group in the South Atlantic, visiting Saint Kitts in the West Indies en route.

The ship and crew visited Manhattan (18-20 October), and then entered the facilities of the Coastal Drydock and Repair Corporation in the Brooklyn Navy Yard for an eleven-month regular overhaul (ROH).

The ship visited Saint Thomas, U.S. Virgin Islands (18-20 April) and refueled at Roosevelt Roads before returning to Mayport on the 25th to begin a restricted availability period that lasted until 4 June.

The ship entered an IMAV at Malaga, Spain (15-26 April), and while there received the Hook 'Em award for ASW excellence personally from Vice Admiral Frank B. Kelso III, Commander Sixth Fleet.

After over two months in port, Hurricane Isabel forced Koelsch to sortie from Mayport, up the St. John's River, to Blount Island on 9 October, returning home the next day.

Koelsch departed Mayport on 2 December to conduct drone services for the Guided Missile Hydrofoil Gunboat (PHM) Squadron 2, based at Key West, Florida.

After placing a prize crew on board the Columbian vessel, the frigate rendezvoused on the 15th with USCGC Nunivak (WPB-1306) and transferred the cocaine and prisoners, along with Granelero II, to U.S. Federal authorities at San Juan, Puerto Rico.

Embarking a USCG team at Guantanamo Bay on 23 March, Koelsch conducted law enforcement operations until 12 April, investigating 112 motor vessels and pleasure craft for contraband during that time.

On 23 March, the embarked helicopter detachment transported a civilian heart attack victim from USS Mount Baker, whose crew had recovered him from his sailboat, to the Guantanamo Bay Naval Hospital.

Koelsch began a two-month IMAV on 2 November 1987, interrupted by a visit to Charleston on 10 December to offload ammunition in preparation for a regular overhaul at Bath Iron Works), Portland, Maine.

On 16 April, the Chief of Naval Operations ordered that the ship be in a "fully functional condition" at the end of the overhaul, but continued ambiguity resulted in Bath Iron Works' falling further and further behind schedule.

The Pakistani Navy completed the training plan on 24 March, covering all areas of shipboard operation and maintenance, with particular attention to engineering watch-standing to ensure the safe steaming of the ship to Karachi.

The Pakistan Navy crew participated fully in all evaluations ranging from cold checks prior to light-off through general quarters, conducting a main space fire drill and gun shoot.