Narrative:

We have planned for a 27K maximum bump bleeds off take-off on runway 28. My copilot and I have done this several times in the last 30 days while not together but both very experienced with the procedures and the airport. We followed the procedures to the letter and fully briefed the take-off. After being cleared for take-off and lining up with the runway I advanced the throttles to 40%. After they were established at 40%; I hit toga. Just as the aircraft started rolling it suddenly surged to the right and at the same time the co-pilot called out the #2 engine not accelerating. By then the #1 was at full 27K 103.1 N1. I was able to retard both engines and was able to keep the aircraft on the runway. We taxied back to the gate and called for maintenance to come out and inspect the tires and write up the #2 engine slow to accelerate after 40% power setting. The inspection showed no damage or wear on the tires and no faults on eec or any other systems.we talked with tech in ZZZ and they said that this has occurred several times on the 737 and was usually the cause of having one engine that is new and the other engine having a lot of time on it. The older engine is 'looser' and may not accelerate like a new engine but when 2 older engines are matched up they accelerate at the same rate so you don't notice the acceleration rate. He said that was the case with our aircraft. Our #1 engine was just installed 2 months ago. Our #2 engine was the original engine installed new recently. The #1 engine has 253 cycles; the #2 engine has 12;588 cycles and is 10 years old compared to a brand new aircraft. I was told by the technician that they just watched a video on this subject and in the video it recommends after the power is set to 40% to leave it there for 20 seconds prior to hitting toga. I told him that is not something we were told about or trained to do.I believe that as our aircraft are getting older and engines are getting changed with high cycles; we should be tracking this combination and have a procedure in effect such as the 20 seconds at 40% N1 prior to toga especially when high N1 is required such as 27K bump; to avoid what could have been a more serious outcome had this crew not acted so quickly and communicated so quickly regarding the #2 engine not accelerating after toga.

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Original NASA ASRS Text

Title: B737 Captain reported a rejected takeoff after #2 engine would not accelerate to match #1 engine.

Narrative: We have planned for a 27K MAX BUMP bleeds off take-off on Runway 28. My copilot and I have done this several times in the last 30 days while not together but both very experienced with the procedures and the airport. We followed the procedures to the letter and fully briefed the take-off. After being cleared for take-off and lining up with the runway I advanced the throttles to 40%. After they were established at 40%; I hit TOGA. Just as the aircraft started rolling it suddenly surged to the right and at the same time the co-pilot called out the #2 engine not accelerating. By then the #1 was at full 27K 103.1 N1. I was able to retard both engines and was able to keep the aircraft on the runway. We taxied back to the gate and called for Maintenance to come out and inspect the tires and write up the #2 engine slow to accelerate after 40% power setting. The inspection showed no damage or wear on the tires and no faults on EEC or any other systems.We talked with TECH in ZZZ and they said that this has occurred several times on the 737 and was usually the cause of having one engine that is new and the other engine having a lot of time on it. The older engine is 'looser' and may not accelerate like a new engine but when 2 older engines are matched up they accelerate at the same rate so you don't notice the acceleration rate. He said that was the case with our aircraft. Our #1 engine was just installed 2 months ago. Our #2 engine was the original engine installed NEW recently. The #1 engine has 253 cycles; the #2 engine has 12;588 cycles and is 10 years old compared to a brand new aircraft. I was told by the Technician that they just watched a video on this subject and in the video it recommends after the power is set to 40% to leave it there for 20 seconds prior to hitting TOGA. I told him that is not something we were told about or trained to do.I believe that as our aircraft are getting older and engines are getting changed with high cycles; we should be tracking this combination and have a procedure in effect such as the 20 seconds at 40% N1 prior to TOGA especially when high N1 is required such as 27K BUMP; to avoid what could have been a more serious outcome had this crew not acted so quickly and communicated so quickly regarding the #2 engine not accelerating after TOGA.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.