Old log book discrepancies

[MN_Flyer]

Hi there....

I am the new maintenance officer of a flight club and have a question regarding log book discrepancies.

My club's Archer is equipped with ECI cylinders that require replacement at 2000 total hours due to an AD. When I subtract my current tach time from the time of the last overhaul when the cylinders were installed and then factor in an offset from a tach replacement, I get the total time on the cylinders. However, it appears that very soon after the overhaul, a mechanic calculated the TSMOH incorrectly on an entry. I have no idea how he came up with the number, as it does not even match the tach offset and appears to come from thin air. Ever since that entry 8 years ago, the times on the subsequent entries have mostly just been calculated using the numbers from the previous one. Therefore, I have eight years of entries that all list the correct tach times but incorrect TSMOH, with the exception of a few that were actually calculated properly.

This is becoming an issue now because I am required to change the cylinders at 2000 hours. If I base the replacement off of the TSMOH, I only have a few hours remaining on the engine. If I calculate it from the tach of the last overhaul and factor in the offset, I still have 100 hours remaining.

What is the correct legal course of action in this case? Do each of the previous incorrect entries have to be amended? Can I just continue making entries in the book using the correct times? Do I need to have the FSDO look at the book to make a determination?

Thank you for any help that you may be able to provide,
Dan

 

[kgruber]

Make a logbook correction. Have an AI inspect your math and ask him to sign as well.

 

[Greg Bockelman]

It is just a math error. I believe what Skywag in the previous post suggested should be more than adequate.

 

[Tom-D]

Karl/Greg got it right, make 1 entry that corrects the error, it should read
" this entry is to correct the time since major overhaul that has been in error since _Date_. Total time and time since major has been corrected to ETT_____ & Time since major _____."

This goes into the Engine Maintenance records.

You can sign the entry with your pilots number or simply as "Owner"

This is not a return to service entry. no A&P or IA is required.

 

[MN_Flyer]

Thank you everyone for your help.

We have an overhauled engine waiting to go in the plane, but the old one is running like a champ and there is no use in wasting 100 hours worth of time on the engine due to an error.