Tower .46 break in
 

Need advise. I'm in process of breaking in a Tower .46 ABC. Using the heat cycling method, ran the engine for 1 minute and then cooled down 5-6 times. Needle valve rich but always 2 cycling. Then did the same for 3 minute runs 5 times. Carefully ran engine up and using a 10X7 prop, engine would peak a little over 13,000 RPM. Set needle back to about 12,500 and ran engine with no sag. Ran for 2 tanks this way. High speed needle at 4 turns. Low speed adjustment difficult and not complete, but with only about a quart of fresh Wildcat fuel through it, I don't think it's fully broken in. Added castor, so oil is about 25%. Very good compression cold.

Engine starts on 2nd flip cold, but hot or even warm I think it would take the rest of my life to get it started even when using an electric starter. Acts flooded. Replaced glow plug with an O.S. #8. Tried different needle settings. Took entire fuel system apart and blew out, including engine and tank. Tank is centered on the carb and fuel does not drain into engine. No bubbles in fuel lines. No holes in fuel lines or tank leaks. Filters clean. Poor compression hot.

Isn't 4 turns a little much for the high speed needle?

Sure appreciate any feedback you may have.

Thanks, Dick.

RE: Tower .46 break in
 

you might want to reset the engine needles to factory setting....especially the low end, that one shouldnt be tuned while engine is running... ive never owned a tower engine so i cant really help much. It should have that info in the manual......

RE: Tower .46 break in
 

Mine acted this way before I sealed the carb. It is a siv otherwise. I also added some rtv to the muffler flange as well. It cured my warm start issues.

Kevin

RE: Tower .46 break in
 

poor compression when warm / hot indicates a couple of things like the engine is still not run in or the cylinder is becoming a little over warmed. set your needle to 2 turns out and run the engine flat out for no longer than 30 secounds , bring back to idle speed for 2 minutes then do the same flat out again. repeat this process for atleast 2 tank fulls of fuel [ 20 to 1 mix ]

RE: Tower .46 break in
 

Maybe just a poor fitting piston cylinder set was sent with this engine. If the engine was not overheated and you had 25% oil, it should have had good compression hot. I think you may need to make a warranty call. Next time don't bother with the heat cycling. It doesn't hurt anything but also doesn't do anything, at least for ABC engines, just run a few tanks through it very very rich. Monitor it to make sure its not overheating. The only advantage to heat cycling is that you don't run it long enough to cause damage from overheating.