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New Member
Sep 23, 2021
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partlow, va
My name is Stanley and I have joined your forum. I looked for the appropriate place to ask a tech question but was unable to find one. I hope asking a question here will be ok.
I have an echine ET1 hit mis engine that lost compression,I believe it is the o-ring on the piston. Where can I get this item. Secondly I removed the crank and did not note the timing position, can anyone help me with this dumb error?
Don't go jumping and assuming it's the "O" ring right off the bat. These engines often have a "Dirt" problem with swarf in the intake and exhaust that get stuck in the valves. The few I've fixed for people all had chips from machining under the valves. Try blowing out the intake and exhaust and if that dosen't work try taking the head off and cleaning the valves and then relaping the valves. I know of one engine that gets run 20 - 30 minutes almost every day and has been running for over 2 years on the same "O" ring.

As for the timing the spark plug should fire the first time just at or very slightky before top dead center (TDC). I've seen this ignition fire twice as it runs. Once when the magnet approaches the sensor and then again as it leaves the sensor. So use the first spark for timing.

Jim G
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