# Can a Hobbs meter be reset to zero?

### Help Support Homebuilt Aircraft & Kit Plane Forum:

#### fly_boy_bc

##### Well-Known Member
I am purchasing some used instruments. They come with an electric Hobbs. I know the answer is probably "NO WAY" :dis: but perhaps it's not as securely set as an auto odometer.

Anybody know how to zero a Hobbs?

Gary in BC

#### TFF

##### Well-Known Member
No. They are sealed. When put in, usually one logs the number on the new meter in the maint logs and total time at that point. I opened one up with a hammer once.

Log Member

#### BBerson

##### Light Plane Philosopher
I can afford a new one.... But I might want to try doing something like this " just because I can". And it's fun to see how things work.

#### cluttonfred

##### Well-Known Member
Buy a new one. If you ever want to sell the plane, then a rejiggered Hobbs meter is going to be a very bad sign for a potential buyer.

#### batesjoe

##### Active Member
Not a directly related observation here, but this thread brought back an old memory. As a young mechanic, many years ago, I recall a flight school down the ramp that would accomplish their 100-hour inspections by changing the Hobbs meter. The guy that ran the place had a desk drawer full of them. The FAA was notified and the school was shut down very quickly.

#### prosafetypilot

##### Well-Known Member
In SOME electric hobbs meters the hours can be reset by grounding the positive and negative terminals...