Visible crew/equipment: When Johnny and Roy are speaking with the Battalion Chief in the apparatus bay, about who could have stolen the money, when they walk forward there are two tape marks visible on the floor behind them, where they were just standing.
Cook's Tour - S1-E4
Continuity mistake: When Roy and Johnny are dispatched to the home of the woman who's in labor, the deputy shatters the door's pane of glass, but there is absolutely no glass on the carpet once they enter the house.
Paper Work - S6-E11
Other mistake: When the little boy is stuck in the storm drain with the rushing water from the broken hydrant, Johnny climbs into the manhole and is submerged up to his shoulders in water while dealing with the boy, but when they lift the boy out and lay him on the grass, Johnny is quite dry except for some wet patches on his shirt.
Other mistake: When dispatch drops tones for the fire at Graymar Plaza, we see Engine 8 rolling out of the apparatus bay and heading down the street, but the problem here is that this footage of Engine 8 is from season 5, episode "Equipment", when Johnny was at Station 8 doing overtime, and we can actually see Johnny sitting there on Engine 8 as it rolls by.
The Girl on the Balance Beam - S5-E18
Other mistake: The dispatcher gives the address of "woman trapped on a wire" as "Commercial Studios,1122 Dellini Plaza", and as Engine 51 drives past the front gates, the large sign reads "World Pictures Corp." Additionally, the address of World Pictures Corp is 1731 Carlson, when we see the same footage of Engine 51 driving past the sign in episode "The Exam" in season 6.
Continuity mistake: When the TV catches fire in the kitchen, Captain Stanley unplugs it, and when it cuts to Roy running into the kitchen with the fire extinguisher, he passes Marco, who just ran into the apparatus bay. All of this while we hear Cap's voice telling Marco, who already ran out, to get the asbestos blanket. Then, in the next shot, Marco is still standing behind Captain Stanley in the kitchen.
Captain Hook - S6-E8
Other mistake: When Roy and Johnny rescue the deputy from the wrecked chopper that sank in the water, they emerge from the water soaked from head to toe, but when they are pulled to the top of the cliff, Johnny and Roy are both completely dry except for a few small wet patches on their shirts.
The Wedsworth-Townsend Act - S1-E1
Factual error: After the car falls off the cliff, Dixie lies unconscious and Roy takes her blood pressure. Roy wraps the cuff around Dixie's arm, then holds the manometer gauge in one hand and squeezes the bulb in his other hand. The stethoscope remains untouched around his neck, even though it's necessary to place the stethoscope bell on her brachial artery (inside of the elbow) in order to actually measure her blood pressure.
The Wedsworth-Townsend Act - S1-E1
Other mistake: Before the car goes over the cliff, Dixie says that the woman has a fractured radius and ulna (forearm), and then at the hospital when Dr. Brackett talks to Dixie he says the same thing, but when Dr. Early walks into Brackett's office, he says "The woman with the busted fibula (lower leg), she's coming out of shock now."
Other mistake: When Pete shows Laurie the newspaper, in the closeup of the article about Gail and Laurie entitled "women paramedics save shooting victims", the paragraphs under and around the title are repeated, and have nothing to do with the title.
The Girl on the Balance Beam - S5-E18
Other mistake: Twice during this episode, when they're dispatched to a "woman trapped on a wire" and also to the "train fire", we see Engine 51 heading out with two firemen standing at the back of the engine, and they are Johnny and Roy. This footage is actually from the episode "The Old Engine" in season 3, when they got the new Ward La France engine for Station 51, and since Roy and Johnny were waiting for the previous shift to return with the squad, Captain Stanley told them to jump on the back and go with them on their first run with the new engine.
Other mistake: When Johnny, Roy, and the cardiac patient are stuck in the stalled elevator with smoke in the shaft, Captain Stanley notifies dispatch that he wants a full first-alarm assignment, and we then see Engine 8 pulling out of their bay and heading to their run. The problem here is that this shot of Engine 8 is from the episode "Equipment" in season 5, when Johnny was doing overtime with Station 8, and we can actually see Johnny sitting on Engine 8 as it drives by.
Loose Ends - S6-E12
Other mistake: At the fire in the freight yard, Captain Stanley asks the dispatcher to respond a second-alarm assignment, and then we see Engine 8 pulling out of their apparatus bay and driving down the street. The problem is that this particular shot of Engine 8 is from season 5, episode "Equipment", when Johnny was doing some overtime at Station 8, and we can actually see Johnny sitting on Engine 8.
Loose Ends - S6-E12
Visible crew/equipment: When Dixie visits Brackett in his hospital room, he insists on seeing the little girl from the accident, but she convinces him to get back into bed. Then as he says "Alright, but later I want to see her," the actor's tape mark is visible on the floor near the second bed, where Dixie stands as Brackett gets back in bed.
Continuity mistake: When Johnny starts chasing Harriet down the street, in Johnny's closeup when he passes the white house (right after the yellow house), there is a light colored wagon-style car parked in the driveway, but in shots from other angles there is a green 2-door parked in that driveway.
Continuity mistake: After Boot shows up for the first time at Station 51, when Chet scares him away, there is a turnout coat and helmet hanging on the hook near the radio receiver base station, but when the dispatcher transmits the tones, the turnout coat and helmet have vanished as Chet turns away.
Other mistake: When Roy and Johnny are waiting in the staff lounge for Dr. Morton, Johnny opens the newspaper's sport's section and sees Brice's picture. In the page's close-up, two paragraphs in two unrelated articles are the same, and they also have nothing to do with the title of the articles. The first paragraph begins, "Thus at this conference all our governments..." and the second begins, "Of no less importance was the common recognition..."
Continuity mistake: After watching Brice's interview on TV, all the guys sit down at the table to eat dinner, and there is one jar of mustard on the table. When Roy smears mustard on his bun, Chet motions for the mustard with his eyes and Roy slides it over to him to use, but in the next few shots the open jar of mustard is either in front of Roy or Chet, depending on the angle of the shot. The milk container keeps switching places as well.
Visible crew/equipment: After Johnny and Roy are called back into the home of the young couple, who were issued the fire-code violation ticket, when Roy is on the Biophone with Rampart, the bulging outline of the mic transmitter is visible at the left side of Roy's shirt, just over his belt.
Fair Fight - S6-E5
Visible crew/equipment: At the cave-in site with the trapped men, when Johnny is up top and also when he's being lowered down to the men, the bulging outline of Johnny's mic transmitter is visible on the front, left of his shirt, right above his belt.
Answer: I believe you are speaking of the old man, Mr. Wilson. He's played by J. Pat O'Malley.
Bishop73
Correct, it was J. Pat O'Malley...he also played the grandfather with his grandson when their rocket exploded, and also played "Old Bill" in the episode with Ann Prentiss, where Gage saves the little girl from the burning tree house, and her mother falls in love with him.