MikeOH

Speaking as a career EE, now retired, there is NO WAY I'm going to trust dual SFs, or any other electronic 'mags'; I've just seen way too many 'unexplained' electronic failures. Despite the ridicule our 'tractor mags' receive the reality is that they have an incredible record of millions of cumulative hours of reliable operation. The odds of BOTH failing in flight are virtually zero. I can see trusting one to 'get you home' if you have a electronic mag, or electrical power, failure. Fundamentally, the fact that my entire electrical system, even planes with dual batteries and alternators, can fail and the engine will continue to run is why I'm an ardent 'tractor mag' fanboy

I've had my plane over 8 years and bought it with 2100, now 2800 SMOH engine. I look at oil consumption (7 hours/qt, looking for increase), compressions (looking for a big drop, flying after a low reading to see if it's real, which hasn't yet even happened), borescope to look for valve issues and cylinder scoring, pay attention at start-up for short-time roughness (indicative of possible valve sticking), and looking for metal at oil change. As long as those things are stable, I'm in no rush to condemn the engine.

At the risk of jumping to conclusions...I think you are going to find that both the G3 and the aircraft's tach signals are coming from the mag switch; they are both receiving the same corrupted signal and are just reacting slightly differently to that bad signal. Since this issue cropped up AFTER you had mag work done...well, sorry to say, I think your problem is with the mag. Yes, I'm relying on the theory that the last thing touched has a high probability of being the cause of a new problem

I've been very happy with my TailBeacon; the X was not available when I installed mine. Honestly, I'm not sure I would have spent the extra money had the X been an option. IMHO, if you are not going to fly outside the US and are going to remain below 18,000 feet I don't see the need for the 1090ES output. If I wanted to fly outside the US, or had a turbo, then I'd definitely get the X.

I was made fun of for checking mags on shut down...until one day the engine did NOT quit! P-lead had opened.

Just remember, your little Lycoming four banger will NEVER guzzle/inhale/chug/wolf-down/gulp/gobble or devour fuel like that IO-720

Works great! https://www.youtube.com/shorts/4WWNhZusLxw

@Ragsf15e STOP THIS!! I'm going to end up selling my F and buying a 252 if you keep this up

While getting a pre-buy is a good idea don’t assume it’s going to guarantee you won’t still have issues. Nor will the pre-buy mechanic take responsibility for what they didn’t find! It improves your odds; that’s the realistic way to look at a pre-buy. My best advice is to buy a plane that has been recently and continuously flown for the last couple of years. It demonstrates that the owner could rely upon the plane which indicates proper maintenance. Could you get lucky with a plane that has sat? Sure. But I think your odds are going to be better with recently flown. Don’t get hung up on high airframe and engine times if the recent usage is good. Honestly, I ran from ads with recent overhauls with only 100 hours; they likely ‘cheaper out’ on the OH. Finally, don’t buy the first plane you look at! Good luck!

I do consider myself pretty lucky!

Over eight years ago I bought my plane ('70F) in this exact situation, 2100 SMOH, and priced accordingly. I purchased with the idea I could be faced with an overhaul at any time I now have 2800 SMOH with oil consumption at 7 hours/qt. and good compressions (>73/80) (I have OHed the #2 cylinder)

This comment wasn't meant as any criticism of YOUR choice. This is an internet forum where contrary OPINIONS are pretty commonly offered up regardless of the OP's desires. Other potential purchasers might be interested in considering if wheel size is important to THEM. Apologies that you were butt-hurt over this.

JMHO, but I can't stand "clown" bikes with the small wheels; I guess riding road bikes with normal wheels has spoiled me. My wife and I bought two Montague folding bikes with 27" wheels. It takes a few extra minutes to pull both wheels off both bikes and stow them in the baggage area and then put the folded bikes in the back seats in their carry bags. While a bit on the heavy side at 30 lbs. they ride close to a regular road bike

FWIW, I had this issue for quite some time, even after having the prop overhauled! Thanks to learning about this 5X 'deep cycle' procedure I no longer have a leaking prop YMMV

Well, for the counterpoint to that...I have had my right tank patched twice in the last 8+ years; both have held and no new leaks have developed. A few hundred each. As you can imagine, I'm in no rush to perform a full tank strip and seal.