Engine vibration

[jgates5454]

Was looking through the parts diagram and noticed this spacer show #24 (PN:0450195) I have never seen this spacer in any other airplane that uses the conical type engine mount rubbers 85 or 65. I do not have them installed on my aircraft. Anyone know why they are there or have seen them. (I’m trying to chase down a vibration that occurs when I transition between 15-2000 rpm and thinking this could possibly help)

(This was happening before I rebuilt my engine now it’s doing the same thing I’ve tried a different prop and same thing)

Any help is appreciated

IMG_1073.png (380.57 KiB) Viewed 1439 times

[6643]

Search the forum for that part number. There's been a lot of discussion over the years. (Not a lot of resolution, though...)

[edidin]

My C120 had the metal spacers and I put them back when I change the conical rubbers in May. A C140 also had them. The Cub whose mounts were changed last week did not have the spacers for what it's worth. I believe, though as John notes there are many opinions, that Cessna specified and used the spacers, but Continental/Piper did not.

[6643]

Oh, I'll bet you dollars to donuts they won't help with your vibration.

Look for something rigidly mounted to the engine that's touching something rigidly attached to the fuselage, like a tail pipe touching the cowl.

[8413]

What carb do you have? Some people have reported rough running in the 15-2000rpm range with the MS carb and one piece venturi.

Have you tried adding carb heat to see if that has any affect?
Josh

[V529]

What carb do you have? Some people have reported rough running in the 15-2000rpm range with the MS carb and one piece venturi.

Have you tried adding carb heat to see if that has any affect?
Josh

Your most likely suspect.........