Hi

I've just bought a new ThunderTiger GP42 glow engine. I installed straight on the plane and setup according to the instructions on the manual.

In the first flight, it was setup to very rich operation. However, after 6 to 7 flights, the engine began to loose compression. When it is cool, the compression is normal. But when is operated for a while (rich), the compression is bad... feel as if there is little resistance when flipping the propeller!

When consulted, the salesman said that the piston has to be replaced! It costs more than half the price of a new engine! It would be better to purchase a new one instead.

Any tips to solving this problem?

Thanks for any help.