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Author Topic: Eachine engines. A question of rings.  (Read 170 times)

Adirondack Jack

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Eachine engines. A question of rings.
« on: September 08, 2020, 09:34:31 pm »
Am I losing my mind, or did I hear in a video about piston rings for these engines, that theyíre supposed to use two rings?  I think it was an unboxing video where replacement rings from banggood.com  were mentioned.  Another reference to someone replacing a ring said they installed a single ring in the lower groove. 
My M91 has two grooves, but came with a single ring installed in the top groove. Itís fine right now, but looking toward the day when I need to re-ring it, I want to do the best set up.

Meanwhile, before I even got the engine, and after seeing the video mentioned above, I ordered a ten pack of rings for about six cents less than banggood gets for four.

Thereís nothing magical about the rings. The eachine reference, replicated all over the net in ads for eachine piston  rings, mentions flourogel. Thatís actually the name of an entirely different product, a laboratory gel medium. The more correct nomenclature found throughout aircraft and other industries, is fluorine rubber o rings. Google that up in the 22 x 1 mm size, youíll get lots of results far beyond the eachine etc engine reference. 

I just wish I remembered who it was said two rings, or bottom groove, and why.

RedRyder

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Re: Eachine engines. A question of rings.
« Reply #1 on: September 09, 2020, 06:05:42 pm »
.
You should have only 1 ring. It was my doing that got Jin to start producing these engines with 1 ring instead of 2.

All these engines in the beginning were shipped with 2 rings. I have removed the extra ring on all that came through the Office of Steam. I always used the top groove to leave the single ring in. Some like the bottom groove. I am not certain it matters which you use as long as it is just 1 of them. The bore is so smooth that with 2 rings it is impossible to get oil between the 2 of then leaving the inside half of each ring to dry out and cause wear, friction, squeaking, and engine dying.

As long as you use white gas which is Coleman fuel or Naphtha mixed 15 to 1 with Marvel Mystery Oil or 2 cycle oil, you will not have a single ring failure for many hours. I have run these all day at shows and have yet to see my first single ring failure.

Gil

Adirondack Jack

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Re: Eachine engines. A question of rings.
« Reply #2 on: September 11, 2020, 01:37:24 am »
Thanks, Gil. I like the thinking about lube failure with two rings.  So Iím good with one in the top groove as supplied. Thatís good to know also.
Iím running zippo and MMO, eyeballing the mix, and it seems to be plenty slippery enough. I stretched the governor springs only slightly, and today, for the first time, after a bit of run in, I was able to tickle the needle valve and get it to single hit A strong pop, with a long Coast between hits when not under load.  Gotta love it.

RedRyder

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Re: Eachine engines. A question of rings.
« Reply #3 on: September 11, 2020, 08:58:15 pm »
Alright, Jack! They are fun little engines. I am happy to see you have gotten it to hit and miss (pop and coast).

Gil

70Rcode

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Re: Eachine engines. A question of rings.
« Reply #4 on: September 13, 2020, 07:23:47 am »
The overly long piston design causes inevitable piston base skirt to cylinder direct metal to metal contact with the current rubber ring position & lack of constant cylinder lubrication arrangement..A factory provided cylinder mid-length positioned drip oiller combined with a Single rubber o-ring at both piston ends would clearance isolate any metallic piston-cylinder scaring & have perfect assured lube viscosity without overly heavy fuel-lube mix ratio exhaust mess...tom.

 

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