OS 40 SF Ring The Second Run

[@Laser100man]

Those older OS engines seem the highest quality ones in my view, can recall a friend at my Club who uses a 1986 (I think?) 108 2-stroke, he's never even had to change the bearing yet. Which I find far more than incredible. Glad to see you back doing engine vids David, was wondering what happened of you the past 1+ month Regards Harry

[@calvinharned6421]

That is a great running engine.

[@randyherbrechtsmeier9769]

Well David, I've been buying engines off of ebay. I just retired and had Heart Surgery. I painted planes at Beechcraft for 37 years. Spent the last 25 at flight as the Piston Painter. Well. I'm starting back into the hobby after years of being too busy to do much of anything but Work. I just bought a Magnum .30 4stroke off ebay. Never Ran, New in the box. Got it the other day. It GRINDS when turned over. Had to open it see what's going on. RUST! The Valves the Head and the Crank all rusted. One valve rusted solid. Got it out. Oiled it. Cleaned a Lil bit. Put it back together. No Conpression. Seller refunded the entire amount. Nice Guy. I think the Valves and head are going to be polished. I'm gonna use Met all. Works great on airplanes. Two questions Ole Wiseman of the Motors. Where can I find new Bearings, they don't seen to be bad. Clean up and use? 2nd and Most important thing. It was a Pain to get the C clips off the Valves, any suggestions? I've just found your channel and it's Very Interesting. Yep I love Saito .45 too. I've never had a S. I keep looking for one. Thanks for all ya Do. Randy

[@dmrcflyr2]

A NIB Magnum with rust eh? Yeah, that is a Chinese made engine for you. Unfortunate for sure. I get my bearings from Brant on eBay. www.ebay.com/str/rcenginebearings?_trkparms=folent%3Arcenginebearings%7Cfolenttp%3A1&_trksid=p3542580.m47492.l74602 I have several videos of removing the c-clips and dropping valves on engines of that design but I could not tell you where or what the video(s) is at this time. Possibly search the Customer Repair engines. I use an appropriate sized box end ignition wrench to depress the retainer and using a magnet in the other hand remove the c clip.

[@dmrcflyr2]

Found this video. Start at the 5:07 mark. kzbin.info/www/bejne/mpqYgYeGmpKXi6s

[@luisgarza2036]

Runs pretty well even at this stage of break in process on FAI fuel, almost at the end of video i heard a boxer twin 4 stroke flying around.

[@dmrcflyr2]

That was a Spacewalker. Uncertain if it was the SIG 1/3 scale though.

[@coriscotupi]

I still have a couple of OS 40F SR engines. It was my best nitro airplane engine, ran like clockwork for decades on end. My best heli engine was the OS 50SX-H Hyper. But my nitro days are over, I fly electric and gasoline only.

[@dmrcflyr2]

Well let me know if you decide to part with the FSR engines that you have. I cold make some videos with them.

[@coriscotupi]

@@dmrcflyr2 Will do. But man, for now it's hard to let go, they're part of my life history. I know, they're just model engines. ...But.

[@dmrcflyr2]

@@coriscotupi Yes, I understand.

[@dmrcflyr2]

I just picked up a used but excellent condition OS 61 FSR at the local fun fly swap meet.

[@SomeGuyInSandy]

I just did a complete rebuild on a OS 46 FX Max. Nice engines, especially with the 40C (or D) carbs. I haven't had time to run it yet, but the compression is excellent, so it should be a ripper!

[@souradeepzkundu3259]

Hello Sir I have a OS95AX brand new , can i run the engine with OS E 4050 in cowl muffler, need your suggestion whether using such muffler decrease the performance of the engine or overheating problems

[@dmrcflyr2]

I am not sure that I am qualified to answer that. What I can say is that any fully enclosed exhaust in a cowl is going to increase the temperature inside the cowling and thus the engine. Depending on the cowl size more than 2x the inlet may be required for outlet air opening size. That can tend to make the cowling look really bad with so much open for heat to escape. Running an engine hotter within a cowl than exposed to outside air will obviously make tuning a bit different and more challenging. Especially since you tune it on the ground without the airflow of flight going through the cowling.

[@souradeepzkundu3259]

@@dmrcflyr2 I will use this OS 95AX in Hangar 9 Carbon Cub 15CC

[@dmrcflyr2]

Knowing that does not change my answer