Garage sales are big head turners for me as well. It's always good to have a few extra bucks with you if you pass by a GS to quickly brose what's there. The best opening question is "have any tools or hardware for sale". You never know what you'll find, it's worth a 5 min stop anytime.

I'm glad I found this (very-very) old post concerning in-flight issues with an OS Max-s 35. I have my first one, a Max-s 30, (totally stock CL engine) on a SIG Banshee and am experiencing the same type of issues. Fox 35 burp type of issue when going inverted, and engine wants to quit on the second loop of an outside.

The original author said he went down to 22% oil on his engine and the in-flight problems went away. So, it sure does sound like the high oil content was the root cause.

I have been running 10% nitro and 28% total oil (50/50) on my Max-s 30 engine. The OS owner's manual for the Max-s 30 I found actually recommends 25% oil. I'll try the lower 25% oil and see how the engine does in the air.

I had similar issues wih a 35s back in the 80's.  A frend recommended some changes.  An Idle Bar Plug, a ST needle valve assembly and a smaller venturi.  Fixed mine and it ran all the way up to 2022 when it was vaporized in a fire.  Oh, we ran 22% oil.

Ken

Goes to show what a few hours of sun & sea will do to a man . Maybe the polititions should try it . Remember , No radios ! . 

Somebodys having a go building another one , so , if you found a sponcer ,you could ' accidently ' get blown ' up the coast ' . If you whipped it through a sawmill before anyone woke up to it , you should be right for a while .
https://vadebarcos.net/2014/10/12/la-kon-tiki-de-thor-heyerdahl/

kontiki II . lets see . how many trees . Would they grow in the back yard ? .

     Supposedly, the original Kontiki raft is in the St. Louis Museum of Transportation here in town. I remember Bob Underwood telling me a story that he received a call from the museum asking for suggestions on how to help prserve the wood. I haven't been there is ages, but it's very near Buder Park  and I'll have to make a stop there someday and take a tour.

   I have been  building models for many years using wood from balsa life preservers that were on the river boat SS. Admiral here on the St. Louis river front. It was an excursion boat that cruised the river for many years, but finally was docked because the hull was too deteriorated. Several attempts were made to turn it into a destination venue or casino. At one time, the construction company doing some renovation work filed a lawsuit against the then owner for non payment on the contract. They won and were awarded everything that was on the boat, including these 2" by 12" by 36" life preservers. I saw an ad in the local paper for them, went to their yard/office to investigate, and came away with 640 of them for the princely sum of $200 !! They were manufactured in the early 30's and some have a date embossed in the end grain. They were on the boat from the very beginning in 1939 and may have been on the railroad car ferry that was cannibalized for the hull to build the admiral on. I had to cut some of them up right away because there was rot on parts of them, but once that was cut away, it was good wood. I tried cutting sheet wood and such with minor success but just stuck with using the wood for blocks and such. i sold off much of the cut up length, and sold whole life preservers every now and then to collectors of Admiral memorabilia. The boat was rammed by some runaway barges in 1996 and it broke loose from it's moorings. People were on the boat gambling and they had to be rescued by fire department boats once a local tug boat operator managed to catch and stabilize the boat. That raised the question on the local TV news and talk radio station on why there were no life preservers on board, even though the boat never cruised any more. I called the local radio talk station with the story, and was interviewed by them, and then on Easter Sunday a few weeks later, local Channel 4 News came by and did a feature on me and the planks that lead off the news that night and was almost 4 minutes long!!  I still have about 150 or so. The Admiral, unfortunately was finally scrapped about 10 years ago I think it was. Such a sad end for a grand old lady!!
  Type at you later,
  Dan McEntee

Oil content over 20-22% is just a tool you can use for more cooling. If your engine is flaming out I would not hesitate to go down to 20% oil and let some heat stay in. That being said, have you tried rasing your tank 1/8" above the center line of the engine?

MM

Thanks MM

I don't claim to know more than the engineers at OS so typically follow what the OS owner's manual says regarding recommended fuel which is 25% total oil. I was using 28% oil (50/50) and will lower to 25% to see what happens. I can also go lower. The engine does seem to run a bit hot as there is fuel/oil brown discoloration on the back side of the cylinder head. I'm guessing this is somewhat normal for this particular OS engine. Ground NVA set is approximately 1/4 turn open from peak rpm, so it should be getting enough fuel for lubrication being slightly on the rich side.

And the fuel tank is already at 1/4" above the spray bar centerline. The engine does burp when going inverted but recovers and the inverted lap time seems OK.

My basic setup on the Banshee:

OS Max-s 30 (stock CL)
APC 10-4 sport prop
Tank centerline 1/4" above spray bar
10% nitro
Ground rpm at approx 10,000
Stock tube muffler with muffler pressure
Brodak 3 oz metal wide-wedge uniflow fuel tank
 

Goes to show what a few hours of sun & sea will do to a man . Maybe the polititions should try it . Remember , No radios !
[/quote]
More like a hundred days - that's how long it took them to get to Polynesia.  By the way, the radio operators (Knut Haugland and Torstein Raaby) actually managed to work a radio ham in the USA from the middle of the Pacific!