Originally Posted by Zabriel

A very old thread but I hope I can get help:
I bought a second hand 87" PilotRC Yak54 with a DLA56 on it. The engine (and the plane) looks as in a very good shape. Bu I am frustrated! I can not start the engine without a starter. As soon as I apply a starter (max 6 turns with a starter) the engine runs great. When it stops, I am able to start it while the engine is hot by hand with a few flips. But when the engine gets cooler again, I need a starter to get the engine running. I checked the ignition, changed the spark plug, checked the plug spacing. Everything is as it should be. Also the carburettor. When it runs, its running great. I have the same problem with a DLE35RA, wich I bought new.. After over 70-80 flights its doing the same. Before I started it also by hand in every condition.
Has anyone had ever a similar problem?

Zabriel

Originally Posted by Truckracer

If this is primarily a cold start issue, I’d look to see that the choke plate is closing completely.

Originally Posted by Zabriel

Checked already. Nothing wrong with them. But a friend told me that the piston rings could be stuck when they are cold. I am going to check them next week.

Originally Posted by Truckracer

Does the engine have good compression when cold and after being run. If so, probably not a ring issue. Do you know what kind of oil the prev owner used? What are you using.

Originally Posted by Zabriel

Both engines have good compressions. When hot, they turn slightly easier. I don't really believe like its a piston ring issue either.
I am using the same gas from the gas station all club members buy their own. I use a total ratio of 1:30, 80% of its content is synthetic, 20% is mineral.