The engineers were warned of fuel problems with the helicopter crashed in the pub The Clutha two months before the accident.
In an investigation, pilot Craig Trott learned on September 30, 2013, how he informed maintenance personnel at Bond Air Services (now Babcock) about problematic fuel readings.
This was eight weeks before the crash that killed 10 people.
Jim Remfry, Maintenance Manager at Babcock, said he would "expect the work to be done".
Mr. Trott was told that two new fuel sensors would be sent to Glasgow to "replace the existing faulty component". However, the technical protocols did not see any changes to the main tank sensors until 10 October.
Mr. Remfry, a crash-time maintenance coordinator, described Mr. Trott's fuel readings as a "discrepancy" rather than a "hard debt."
He said he could only assume that the sensors were being sent and kept on standby.
The investigation at Hampden Park showed the exchange of mail between Mr. Trott and Mr. Remfry with the subject "G-SPAO Fuel Indications".
G-SPAO was the registration of the crashed police helicopter.
Mr. Trott said after refueling to 310 kg in the main tank, he had noticed that it reduced two hours later to 295 kg and after launch increased to 320 kg, before it reduced during the flight again "with normal burning rate".
In his e-mail, he wrote: "I understand that you will calibrate two new fuel probes and send them to Glasgow to exchange them with two others on the plane."
The pilot said he would continue to operate the vehicle, adding 30 kg to his calculations for the minimum fuel and informing the on-duty pilot of the next day.
Replying to Mr Trott in an e-mail on 1 October, Mr Remfry replied: 'I have taken up this problem with Martin Forster, avionics manager, who has accelerated an existing demand for two of the later fuel sensors.
"He is confident that we will receive them at Staverton next week and will then come up with a plan to replace the existing flawed component."
No record of change
The maintenance manager said he was pleased that Mr. Trott continued to fly the helicopter and included the problem in his flight planning calculations.
In technical protocols covering the period up to 10 October, no records were kept of replacement of the main fuel tank sensors.
Mr. Remfry said he could not remember if they had been changed, and assumed that the job had been done.
When asked if it would worry him if the work were not performed, he replied, "Yes, I would expect this work to be done."
Previously, he had informed the investigation that the pilots had received a series of reports from Bond regarding discrepancies between the amount of fuel being dropped into a plane and the fuel gauge reading.
"This has been discussed in detail by our management team," he said.
Pilot David Traill, 51; PC Tony Collins, 43; and PC Kirsty Nelis, 36, died in the crash, along with seven customers who were in the bar on Stockwell Street.
They were Gary Arthur, 48; Joe Cusker, 59; Colin Gibson, 33; Robert Jenkins, 61; John McGarrigle, 58; Samuel McGhee, 56; and Mark O & # 39; Prey, 44.
The investigation in front of sheriff director Craig Turnbull continues.