Go with LORD mounts
LOCKNUT said:
Has anyone used the Conical Lycoming Engine Mount Bushings sold by Aircraft Spruce P/N 08-00662?
That is pure junk. You get 8 of those, 8 big washers and smash them down to an inch of their life. They isolate vibration like (fill in bad word here). They also don't last and wear and sag very quick. You want a LORD mount.
Get the LORD engine mounts. They are expensive but worth it. I think van has them for sale ($75). The part number I recall is J-1552 ($34.95 each, you need 8). The alternative part number is J-6230-1 and they are sold in pairs for $78.95, you need 4.
The temptation to go with a $8 bushing is high, but you will not be happy. You will be replacing them and unless you have a wood prop chance is you will be unhappy with the vibrations. The "Homebuilders conical Lyc engine mount bushings that Spruce sells cost $40 for the whole set. Yoy will need 8 large washers at $7 ea, or $56. These are larger dia and thicker than plan old AN washers. So you are into it for $100. For less than $300 you can get REAL engine vibration isolation mounts.
The LORD vibration isolators are like a Dynafocal design for the conical mount. Trust me, done that been there. Call LORD at Customer Support Center +1 877 ASK LORD (275 5673) to confirm part numbers. If you buy form Van's make sure they are LORD brand. I am not getting anything from this, but I have tried all brands and types and the LORD cost a few pennies more but are well worth it. The cheap "Bushings" are just squashed down. There is no torque because all you do is smash the bushing out from around the washer. IT SUCKS.
The Lord Conical mount has built in washers and spacers so they are easy to preset and not over crush. They are just a world apart. I had a vibration problem with my RV-4. I tried evey thing. My extend hub hartzell was balanced several times but was never quite right. Going from bushings to the LORD mounts was like going to calm sea's.
The bushing deal with conical mounts is a weird things. Back 60 years ago they used them for shipping. The bushings are good for shipping but not aircraft use. Bite the bullet and pony up the better part of $300 for the real deal. The bushings and the proper washers would cost you only about 1/5th of that, but if you have to replace them all the time and rattle you fillings out, it is not a deal.
