Muffler Springs & RTV

[yankee-flyer]

Well, for the moment (at least) my exhaust pipe is centered in the cutout side-to-side but hits the aft end-- easy fix. My real question is, we're supposed to put hi-temp RTV in the muffler springs. It's not clear whether you're supposed to completely fill the springs (make a solid cylinder) or just fill the spaces betweel the coils. Either way looks like a pretty messy operation-- if you completely fill the spring won't that make it extremely difficult to remove the muffler for inspections? What have you who are past this point done?
Thanks very much

Wayne 120241 (who spent WAAAYY too much time on that blasted colwling)

[sandpiper]

Do not fill the spring. A wide bead of sealant down one side is sufficient. Mine is maybe 0.2" after being wiped lightly with my finger. I made no special attempt to work any of it into the spaces between the coils. The idea is to stop the vibration that can cause early spring failure. Before I put it on I would find broken safety wire about every oil change.

[Geico266]

Use gray or black high temp RTV. It looks much better than red.

Goop up the spring hooks where they attach to the muffler rings. It helps keep them from wearing by holding the spring in place.

[jte65]

Originally Posted by sandpiper

Do not fill the spring. A wide bead of sealant down one side is sufficient. Mine is maybe 0.2" after being wiped lightly with my finger. I made no special attempt to work any of it into the spaces between the coils. The idea is to stop the vibration that can cause early spring failure. Before I put it on I would find broken safety wire about every oil change.

The builders manual specifically indicates that the spring should be completely filled. I filled mine and it was not difficult at all. It all stays within the spring and therefore looks decent when it is done. There is enough give in the RTV that removal should not be an issue (other than needing to repeat application on the spring hooks).

Jeff

[Geico266]

Jeff, I remember that part in the plans, but IMHO filling the spring is not nessessary, IMHO. It certainly would not hurt anything, just added weight. It not a bad idea to replace the springs every 2-3 years anyway. They will all break eventually. A nice little item to pick up at OSH which is only 14 DAYS!

[sandpiper]

Jeff,

I could be wrong, but I don't think the rest of the 912 world fills the spring completely. It certainly was not what I was taught in my LSRM or Rotax courses. Probably can't hurt anything though.

My experience is pretty limited so I would be interested in hearing from those who have been doing this for awhile or who do it for a living.

[D&M Dan]

Anybody got a picture of the springs with the RTV installed? I am confused what it looks like. The diagram is somewhat confusing.
Thanks

[RFSchaller]

I filled mine 3 years ago. No issues so far.

[Sink]

This was discussed on the Rotax forum a week or so ago.

Here is the link and a picture that someone posted that should help with safety wiring and siliconing the springs in a better fashion.

http://www.rotax-owner.com/en/rotax-...-springs#10938