Vibrating Panel Question

[Jeff_S]

Hello all,

I test flew another J this week, one I really like and am about ready to move forward with. I noticed one thing during the flights that was interesting to me. The left side of the panel, where the standard six-pack is, is mounted on rubber shock absorbers I guess because it was vibrating noticeably, especially on high RPMs at takeoff. Once we dialed back the RPMs for cruise climb it dropped considerably but was still jiggling a bit.

I've not flown in enough Js to know whether this is common or cause for concern. Neither the owner nor the CFI I flew with, who flies the bird regularly, were that concerned about it. The CFI suggested maybe having the prop rebalanced would help solve the problem. I didn't see anything in the logs that would suggest this has caused continuous problems with the gauges (e.g. no consistent or frequent repair/replacement) but it would seem to me that it's not a great thing to have your gyros constantly jiggling like that.

Any ideas?

[hansel]

Welcome to the world of the four-banger Lycoming. This is par for the course and probably one of my only beefs about the 201. But given the efficiency of the plane and rock-solid reputation of the engine, I'm willing to accept a little vibration. If you fly your 201 for awhile then hop in say, a C210, you'll really notice the difference-- particularly at low rpm (startup/shut down or the "yellow zone")

The biggie with the IO360 will be keeping up with possible oil leaks that develop from all the shaking. You'll want to become comfortable pulling off the cowling on a regular basis to monitor the engine and everything attached to it.

Balancing the prop will help (every 500+ hours is a good idea), especially with a two-blade, but the bottom line is that the vibration will always be around. Don't worry, you'll be too in love with your Mooney to let it bother you.  Good luck! 

[Kwixdraw]

I would just about bet money that a couple of the rubber dampers behind the panel are broken.  You can't tell without getting behind there and just a couple will cause the load to overload the remaining good dampers. One of the little things that you'll find on the J.

[rotorman]

My airplane was built in 1980. When I checked under the panel a few years ago, I found all the dampers had disintegated. I bought all new ones and replaced them. This is not an area most people inspect closely. You have to get under the dash with a flashlight and inspect each one.

[Jeff_S]

Thanks guys. So the obvious follow-up: how much effort is it to replace those dampeners? Is that an "average" maintenance job (e.g. a few $$hundred) or something larger?

[Kwixdraw]

Jim's right, the rubber mounts are a nothing in the grand scheme of things. Might cost you a hundred bucks to replace all of them if you can turn a wrench. Look hard for thr "right" aircraft and don't fall in love with the first available one you run across. That can be a real moneypit.

[Jeff_S]

Yeah, that's pretty much what I've determined re: the vibrating panel. It's not a deal stopper by any means, just something to keep in mind and I'm glad to know there's a relatively easy fix.

As to my progress, it's going quite well! I've got the P&S done on this plane, and it's scheduled for pre-buy on January 6.  So if all goes according to plan I'll be flying it home sometime in the next few weeks.

Anybody want a nice, well-equipped Warrior?!

:-)

[Brooks]

i had my plane in for the IFR pitot static check and my avionics tech found that most of my mounts were broken. 

he did not have them in stock so he gave me the part number. i ordered them and after about $45.00 (you need 10 in a 231 (K))plus shipping i had them.

it took about a half an hour to replace them. the trick is to work your way arround the panel dont try to take it off completly.  second make sure you get the safety straps back on correctly. this is what prevents your pannel from ending up in your lap when you break them again.  have a needle nose pliers handy to get the studs of the broken ones out, and dont over tighten. be prepared to be on your back for the bottom ones.