Hello everyone, I’m looking to get some input on the proper way to lean a 172. It’s rather embarrassing to admit, but long story short right before my cross country in PPL I switched schools and flew Diamonds through my training all the way to getting my PPL. For those who are familiar with a DA-20, you’ll know that you watch the EGT gauge when leaning and, what I was taught, was two clicks rich of peak temp. Easy.

However, I am time building for commercial and have found a 172 to rent at a cheaper rate, and have done a checkout and all was well, went for a flight over the weekend and once I levelled out at 3500ft en route I thought to myself “oh shit, this doesn’t have an EGT gauge”. I felt so stupid to have not asked about something which is rather important like this, and have not been able to speak with my instructor recently. In the situation I was in I ‘unscrewed’ the mixture until the slight rise in rpm and gave it a generous two turns rich.

Is there a better way to lean the mixture in a 172K model, other than going off just the RPM?

Thanks!