I'm in the process of setting up my 12 HP single Cylinder Ruggerini Diesel with an induction motor for a generator and a couple of 80A Alternators.
Much like my roid, this thing seems to be quite the thumper. I got some 3x4" hardwood pieces I cut 1200 mm long and bolted the thing to that. It walks around the concrete even with my 120KG fat backside on one end with a 20Kg battery and the 46Kg motor on the other. It doesn't bounce like the roid, more of a vibration that causes it to walk around. I have not hooked anything up to it as yet as i'm waiting for a pulley to be machined.
I then found some Subaru Gearbox mounts which are very soft and put one on each corner of the engine and bolted it to them and then screwed it to the timber with coach bolts. that mainly stops the frame walking round but now the motor seems to vibrate the starter motor hanging off the side a surprising amount. I thought it was an optical Illusion but I jammed a screwdriver between the starter and the block and it stopped waving around.
Yes, it is bolted tightly.
I also recently got another single cylinder Diesel on a water pump and that thing wants to walk around on it's steel frame as well. It's OK if I put a couple of lumps of styrofoam under the frame and on the concrete but after a day or so it compresses the foam down and hammers and wanders off.
Neither engine seems inherently out of balance, the faster they run the smoother they get. I think its something to do maybe with the engine slowing down for compression or the boot it gets when it does fire.
Will this stop or be reduced when the engines are driving something? I was thinking to try and add wheel weights to the pulley of the electric motor but then as i'm thinking of driving it with a V belt, that isn't going to work. I do have some cam timing pulleys and belts but they are too small to add any balance weights to so back to square one... and that's if its needed of course. Maybe the rotational mass of the induction motor will smooth things out?
I'm wondering what is the best/ correct mounting method with engines like this? Should they be rubber mounted or does that allow for fatigue inducing vibration? I can see that starter motor breaking right off the cast backing of the blower housing given not too much time. Should they be hard mounted but if so, how does one stop the mounting walking around the concrete? I don't want to bolt these down as yet.
If I put them on rubber wheels, will that fix the problem? Can they be like hard rubber castors or to stop the things walking to they have to be inflatable tyres?
I think I'm asking something basic and probably stupid here that all the experienced Engine operators would know but I am ignorant at this point.
