Mery 6-stroke kit.

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Jack3M

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A bit longer run, in fact the longest yet. Had to make a new crankshaft after a backfire (I forgot to pin the darn thing first time around) Also got the water pump mounted, need to plumb it.
 

PhilL

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LMAO!!! I recognize that cry at the end!!!!
It will be like that for a bit. It will run for a bit then quit. You'll find something needs tweaking, then it will run a bit longer; rinse, lather, repeat.
It does sound like it's firing a bit out of balance. I didn't slow the video down to determine which side is weaker but you can do that. The video capabilities now are great for slowing down time and seeing what's happening. Check your compression balance and look for leaks. Especially on the rear packing.
 

Jack3M

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Actually the rear was not firing at all, did not get hot. Valves leaking. (intake) Both sides actually compression gone.
 

Jack3M

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Damn, get it all back together, needed a new O-ring, I used the wrong type. Regardless, the damn thing sheared the tapered pin and silver solder on the flywheel side. Maybe I need to make one piece crank?
 

PhilL

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Oh no... That sux!
I've always done 1 piece cranks. I guess there are pluses and minuses to each.
You may want to look into timing? The power stroke may be a bit too early and resulting in a more violent stroke. Since you aren't really powering anything, there's no need to fire too much earlier than TDC.
 

Jack3M

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That is where I guess the timing to be, TDC Using the timing light on the ign and visual on piston location/crank. I am pretty much lousy on working steel with any kind of decent finish. Did you start with 5/8" for your one piece?
 

Cogsy

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What ignition are you using? The REXEL types have built-in automatic advance and fire way advanced at even slow running speed compared to turning over by hand (I've been caught out before).
 

Philipintexas

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I have a piece of 1” X 10” CRS left over from my Mery, I have about $10 in it but shipping would probably be prohibitive. I’m in zip 75154 is it will help.
 

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