Engine Vibration- Isolating??
 

After trying to adjust the high speed needle valve recently, I realized how intense the vibraiton is in these small engines. I couldn't hardly hold on to the neeble valve. I am aware that extensions can help with this but I am more interested in isolating the vibrations to engine mount cheaply. I know about the isolation mounts sold by various manufacturers, so this isn't what I am looking to do. I don't want to unload a ton of money to do this. Rather, I am wanting ideas to build my own. One idea I had was to find some rubber material and cut round disk to mount behind the engine mount itself. They could even be different thicknesses to help control torque in the air. If you have experience with this please post your ideas to help me and others out.

RE: Engine Vibration- Isolating??
 

Here ya go...
http://home.online.no/~ofremmi/Articles/Articles.htm

I thought about doing this, but central hobbies had my hyde type a mount on sale for $60 do I did not bother...

RE: Engine Vibration- Isolating??
 

Hello; I have fooled with anti-vibration mounts for years, with some success, and some failures. I tried what you mentioned on my Decathlon and a 70 OS. I found that if I tightened it up enough to keep from loosening, it didn't offer much vibe dampening. and if I used nylock nuts, so that I didn't have to cinch it down tight, the vibrations would eventually hog out the holes in the firewall. I had more success with "Lord mounts", these are bolts glued to rubber with the male threads on each end. They are available in all sizes I used dime sized ones. They were maybe 3/8 thick. They worked pretty good until they started to de-laminate (about two years) I think the oil and the heat reacted with the rubber and deteriated it. I have tried every anti-vibe mount known to man, and have now settled on the Dubro mount, as it is all that I can find here. It is expensive, but it works, and I think the benefits out-weigh the cost.

RE: Engine Vibration- Isolating??
 

I'm assuming the obvious but you have balanced your prop? Have you tried a different prop? Try moving your existing prop to a different position on the crank. Sometimes just doing that can really effect the vibration.

RE: Engine Vibration- Isolating??
 

I think the plastic motor mounts are better at absorbing vibrations that the aluminum ones but I could be wrong. I wonder about a solid wiece of rubber behing the mount cut to shape of mount. I recently took of a metal motor mount on a Ultra Stick that weighed 4oz and replaced it with a Dave Brown mound and save about 3oz. The Dave Brown mount weighed a little over 1oz. I wondered at the time about cutting a solid piec of rubber a bout 1/8" thick and sticking it behind the mount but I decided I didn't have a piece that I knew would resist the fuel. Any thought on this idea

RE: Engine Vibration- Isolating??
 

You can buy the exact thing you describe from Davis Model Products, a rubber sleeve goes in the firewall and rubber washers go on each side of the firewall. You can tune the damping with tighter and looser applications, also you can adjust the right and down thrust by tightening certain bolts differing amounts. I use them on my Diesel applications so the airframe doesn't sound like a drum. They don't let the engine move much but do an excellent job. You can add more washers to the front for a softer mount.

RE: Engine Vibration- Isolating??
 

Have a look at "Using a mousse can motor mount muffler" at http://home.wanadoo.nl/pereivers/cad.../cadviews.html ; It points to the viewer version http://home.wanadoo.nl/pereivers/cad...ssemuffle.html on my web CAD section This uses grommets and spacer bushings. Also look at http://home.wanadoo.nl/pereivers/STinstall-2.jpg . I use this backplate mounting method on all my engines from .10 (3 grommets) to 2.15 (4 grommets), and plan to use it on even larger engines like 3.60 using 6 grommets.