So I balanced the flywheels to zero (both flywheels within thousands of each other with keyway up) one flywheel was off by 1/2 inch one way the other was off the opposite way about 3/8, took about 3.25 oz on one flywheel and 3.0oz on the other to get them evened up with the keyway perfectly up. Put it all back together and while it is about 10-20% smoother, certainly not where I would like to see it.

I am wondering if there is either not enough counterbalance weight or too much? It would seem to me that the crank counterbalance should be offset by the flywheel counterbalance, just because the flywheels are both home at "zero" does not mean they have enough or too much weight in the counterbalance area to counter the crankshaft? Is  the right answer, to disconnect the connecting rod and balance both the crank and both flywheels at the same time?

And the obligatory pic and video (pic was taken while it was still rocking back and forth)
You may notice the slice in the wall in the video, this was from my makeshift fuel tank bracket before the frame was bolted to the floor, it walked over there and cut a slice in the wall....I will use that area for the exhaust pass through now....




[youtube]http://www.youtube.com/watch?v=u3IfViKqNX0&feature=youtu.be[/youtube]

This thread and not having the inclination to Muscle round the Roid to balance it, made me Dig out my little China Horizontal today.  As soon as I got it out I remembered the biggest drawback with the thing was that Damned Pulley.  I was thinking about trying to find some plate and get my brother in law to centre it up for me on his lathe so I can weld in a shaft and get him to put a 3/4 and 1" step in it.

I have some large faceplate like things off a lathe that I picked up from a scrap bin outside of a machine shop that are probably heavier then the original flywheel. I might talk to him about what these would need to bolt up to the flywheel and put the shaft on one of those.
Might be better to go somewhere and have them done, he's a fine machinist but I'd be lucky to get the things back by christmas....... next year.

I looked on some China engine sites and the only thing I found for those engines is the original flywheel and pulley. Not much good to you.
perhaps having a plate and shaft made to fit may be the easiest option for you?

While looking, I noted the starter motors on some slightly smaller machines.  They were .7 KW.
Seems that even if your starter is double that, it shouldn't pull massive amounts of Current.  The starter on my Merc was 3Kw and the one on my truck is only 2.7 and normal batteries and cables spin them up just fine.

Of course being a new engine everything is going to be tight so that may have an effect on the cranking effort.
My little engine hasn't got a great deal of hours on it but trying to turn it over today without the compression release was impossible no matter how slowly I tried to turn the flywheel and let the compression escape through the piston rings.
As I suspected might be the case, the injector pump was stuck, again, so I pulled that all apart, cleaned the gum out and got it firing again nicely. It was well and truly stuck this time and it proved hard to get apart especially the main plunger but all good now. Pressure pack $2 degreaser works great cleaning those pumps and gets everything moving again.

All part of the fun I suppose but I'll make sure to run the thing on engine or 2 stroke oil before I put it away again this time and drain the tank which is also gummed up.

Why do they put such useless fuel taps and tanks on Chinese engines?
 All my china engines fuel caps leak as do the taps where fitted.  I never fill the tanks as it gets shaken up and comes out to run all over the engine.
Pain in the Butt.

Same for me, I have hunted all over the Chinese sites, and it looks like either I need to have something made from scratch or have the existing pulley modified so I can put a coupling on it. I did a quick drawing / quote on emachineshop.com and it came out to $600 for a steel adapter, seems kind of pricey to me I will have to do a real drawing and check  some local shops.

The bouncing  fuel tank has got to go!

That's just temporary, being held in place by a bungy cord on a half assed couple brackets I through together in 10 minutes because the regular brackets didn't get shipped with the engine. I have a custom spun aluminum tank on its way which will mount on a separated frame so no shaking at all.

Yes, it does look like there is a bit too much vertical movement in that machine.

Suggestion:
Before you start pulling flywheels and adding weights, try moving to a different speed (without loading the generator because your voltage will not be correct anymore).
All we are testing for is critical frequencies.
My 6/1 shakes like a #$@% at 500 rpm but smooths out nicely above and below that speed.
So.... try that first just to make sure you have not set up a destructive bounce in relation to the natural frequency of the rubber isolators.

If you find that it solves the problem, then proceed to change the generator pulley to match the smoother engine rpm.

good luck,
veggie

I did try finding a sweet spot, and lower rpm did reduce it slightly but not enough for my taste.

Ordered a shaft, bearings and stick on wheel weights to go ahead and balance the flywheels this weekend and see what it gets me.

Looks about the same as mine was under load when I had it bolted to 3" wooden runners which were bolted to the concrete.

I think like me, you need to look at getting the thing balanced up. You might be able to stop it by filling the frame with concrete but I think that's a bit of a band aid solution to an underlying problem.  

I see it as a lot of extra stress on the engine and components and at the end of the day they just shouldn't be like that.
 If the weather is good, I might have another crack at mine tomorrow.

I would agree, it would seem I need some additional balance work.  I ordered the gib puller last week so I can pull the flywheels, guess I need to get busy this week and build a balancing fixture.

I have to wonder how much injector timing could be contributing to the shaking?



 

I'd sure like an engine like that and especially for that price!
You are getting a nice collection. Not going to be a power shortage at your place that's for sure!

I have one of these style engines and it's a real beauty. It's only the baby model but if the big one is anything like it, I'm sure you will be really pleased with it.
The flywheel does look pretty light on your one compared to my baby horizontal. The flywheel on mine isn't as large but much thicker.
Of course mine is tiny compared to yours but when I wind mine up and flip the decompression lever it will spin it through a couple of compressions.  That doesn't happen often admittedly, it usually fires right up even on straight WVO no matter how long it's been sitting round.

Dare I say it but I think so far that engine is my favourite even over the 'roid.
The only drawback to it is the thing is the noisiest engine I have by a good measure. Yours may be a lot quieter as mine is not water cooled like yours which should help a lot in the sound department. Then again that may not be important to you being on a farm and not having neighbours 30Ft away.

Looking forward to seeing pics of how you set it up and vids of it running.

The changfa clone is being built up as a back up / standby gen for my residence and I have neighbors within 30 feet on either side, but not behind me...that is all woods. I would have used a Listeroid but my wife is dead set on having AC during a power outage and I would need a monster 2cyl Listeroid to generate the minimum 15kw I need, a 30hp Changfa seemed like a better answer.

I see my plan is failing....I was masking my collection as useful equipment...and you saw right through it, wonder how fast the wife  catches on .... 

 ok, got the frame mounted on the isolation mounts, cannot feel any vibration in the floor, obviously the engine is now fixed to the floor and not walking, however the vibration seems high still, if you look at the top of the engine in the video you can see it is shaking pretty good...to me (this is my first listeroid) it seems too shaky...it looks like over time it will shake itself apart?



[youtube]http://www.youtube.com/watch?v=rbP9DvQZWEo[/youtube]

 Seems like it would be faster and easier to just pull the wheels off and balance them first and then do the trial and error to get the last 10% if necessary.

I have a wire welder and some steel around, plan to make a wheel balance fixture so I can at least get the wheels balanced to each other and see what happens. 

For the moment though, I am too impatient, going with mounting it to the floor using the isolators so I can run it more than 30 seconds