Lycoming O-235 Help

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Location: Fernandina Beach, FL

Lycoming O-235 Help

Post by BBonds45 »

Hey Everybody,

New to the board and this is my first post. I acquired this boat about a month ago that had been in the family for a while. It's 12x8 with a Lycoming O-235. I am somewhat mechanically proficient but have no experience working with aircraft engines and am stuck. The boat has been sitting for about 3 years and won't start. I drained the fuel tank, replaced the fuel system and filters and put good gas in it and replaced the battery. The engine will turn over but won't start, and the positive lead to the battery starts to smoke. The wiring is a mess and I don't even know where to start to rewire it. I read several articles about ground issues, but I am not sure what needs to be grounded. I see at least on ground wire from the block to the cage.

I live in Fernandina Beach, FL and can trailer her, but was looking for some inputs on local mechanics that can help me figure this out and get her running again. Anyways, I would appreciate any help/input!


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Re: Lycoming O-235 Help

Post by Planeguy »

Smoking wires come from too much resistance. I suspect bad connections if not bad wires. Make sure all the battery and ground connections are clean. If you can use a multi-meter, it may not hurt to do a resistance check to make sure the cables don't have bad spots in them. Overheating could also be caused by using too small a cable to carry the load or the starter going bad or not being grounded well.

The carburetor could be gummed up or corroded. Especially if auto gas contaminated with alcohol was being used then allowed to sit with bad fuel for very long.

If you are getting fuel to the cylinder then it is time to check spark. The stock magnetos generate their own spark (battery not required). The small leads that come from them may be shorted to ground somewhere or something inside could be bad (condenser, coil, points...). Since mags generate their own electricity it is generally a good idea to show a healthy respect of the propeller because an aircraft engine can fire at any time if the prop is moved and the mags are not grounded.

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Re: Lycoming O-235 Help

Post by ffjpowell »

Hey Brett,
Call me tomm when u get a chance. I live in jax southside. Know a great ac mechanic and is a airboater.
Jason Powell
What the mind of man can conceive and believe, the mind of man can achieve.

Live today like theirs no tommorrow.

New build on the way!!!!!! Stay tuned.

J. Powell

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John Fenner
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Re: Lycoming O-235 Help

Post by John Fenner »

Points are likely corroded, use search tab and look for point setting, cleaning, should be a few on it.
I never finish anyth,,,.

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