You said that you have been flying for five months and thats great but its hardly enough time to have an exccessively coated engine and to need to remove an give it crock pot baths or as one poster said to remove and take off carbs, and back plates so forth.

Yes those techniques do work for a thoughly coated engine but its not time for that yet.

If a little discoloration around the cylinder head and around the header/muffler bothers you, just reduce the castor content of your fuel as one poster noted simply by changing to one with less castor or simply no castor.

The fuel you use is about one third of the oil is castor. You will find far more folks use fuel where about only three percent of the oil is castor. Thats for some of us who prefer to retain some of the benefits of castor. Or you can just use fuel with no castor.

In the distant past all glow fuels consisted of 100 percent castor and yes the varnish built up far faster and yes if you wanted a pristine engine it was neccessary to remove and cleanup far more often. Most folks back when just did not worry about it much as running problems from this were much, much further down down the line.

John