I'm looking for an O-300D engine or good crank for same...

I believe Aircraft Specialties has one. $$$

I would call Kelly at Aviation Airparts in Oceanside CA. When the employees purchased the business from Rick and Ann, I’m pretty sure it came with a large parts inventory. They are really good peeps too. 760 721-1389

Great thread here as I have a 172G (same as the H) and looking at overhaul options. I have almost 2500 hrs on my O-300D and it runs well with a second set (some third set) of cylinders on it. Doesn't burn oil, and oil analysis every oil change shows everything stable. I like the smoothness of the engine and have never taken it to the mountains. For all these reasons, I am looking for someone to overhaul, rather than an upgrade (although the Airworx option looks interesting).

I'm told the challenge with these engines is getting the parts (other than cylinders) and would be interested in hearing from anyone who has had good or bad experiences with overhauling a O-300.

Magnesium Oil sumps and accessory cases are a problem corroding from the inside out with no signs on the outside until the oil starts seeping through the casting pores. Also engine mount legs corrode.

Some of the "Repairs" I have seen were coating the inside of these items with what appeared to be JB weld and painting the insides of them.

there was a reddish coating I believe applied by the factory inside the later engines. There is a name for it but I don't recall the name. I find other coatings peeling off the inside of the case when the engine is disassembled.

Interesting. One of the few negative comments on Powerflow I've heard. I added one to my first Tiger when the muffler required replacement and found the performance gain significant, and did not notice much if any difference in sound. I liked it enough to put one on my second Tiger when I acquired it, even though the existing muffler was fine.

I recently completed a 210hp STC upgrade on a 172E. It has a constant speed prop with a Continental IO-360G, and its climb performance is outstanding.

That being said, it was a long process. I am doing a 170 next, but while the performance is great, it does have a lot of details which aren’t intuitive when you read the installation instructions.

Who’s STC did you use?

I had that same experience in my 172N with the Penn Yan 180 w fixed pitch prop. Great useful load and tremendous climb. We upgraded to the Bonanza for more speed but I often miss the useful load of the 172. Four adults, full fuel and some luggage? No problem.

Interesting. One of the few negative comments on Powerflow I've heard. I added one to my first Tiger when the muffler required replacement and found the performance gain significant, and did not notice much if any difference in sound. I liked it enough to put one on my second Tiger when I acquired it, even though the existing muffler was fine.[/quote]

Powerflow ICA

https://drive.google.com/file/d/1s2GJdD ... view?pli=1

6.2.3 Page 21. All slip joints need to be disassembled and lubricated every 12 months.

That's muffler to header pipe joints, tail pipe etc. Whole system needs to come off and reinstall to do this every 12 months. You can cheat a bit with one side but it's still a pain.

Observing the Difference from the right seat looking down between 172s in many trips around the pattern directly over our town (normal approach and departure). people look up at the Powerflow airplane, They don't look up at the stock 172s. People call or stop me in the grocery store and ask "what was that airplane today" when I give dual in the Powerflow 172. They don't with the stock 172s.

Who’s STC did you use?