So I just lost the back half of my muffler for my OS 46AX. Gone. Walked around in the snow for awhile to see if I could find it, but no luck. I was too busy witha dead stick landing to really see when and where it dropped.

Looking for suggestionsons on the replacement. Should I get another stock one? Is there a better/cheaper alternative? Is it worthwhile to seek something that will give it better performance?

TT 46pro use to be an exact bolt on an a whole lot cheaper than an OS.

Go here:

[link=http://www2.towerhobbies.com/cgi-bin/wti0001p?&W=000213529&I=LXJB16&P=K]Tower Hobbies Muffler[/link]

and buy it.

This muffler is cheaper and way better than stock. It will transform your 46AX. I use them on a 46AX, 50SX, and two GMS 47 motors. In fact, I replace the stock mufflers before I even start new motors.

Live long, and prosper
Jerry L. Gubka

I recommend the Tower Hobies muffler also. You need to use Loctite on the muffler screws and Silicone Automotive Adhesive Sealant on the muffler to engine flange and the muffler halves.

I now use the mac one piece muffler that tower hobbies have. They are not cheap but they do look cool. If you replace with a stock style muffler drill out the screw holes that hold,em together and use a thicker bolt with loctite.

Looks like you have some good choices here.

Thanks guys ... I'm going to order the tower muffler. Looks like a good choice. Cost and performance. Perfect.

Thanks again

when you get it replaced use either 60 thousands wire or a nylon strap fastened to the mounting area by the engine and wrapped around the second half of the muffler where the exhaust is. the reason they come apart is the center bolt comes loose and vibrates off. with safety wire or a nylon strap all you will lose is the center bolt and that is easier to find than the back half of a muffler. I had the same thing happen to me and started safety wiring the sections together.

Here's what I do to my mufflers so I don't lose the back half.

Ken

My club races Sky Raiders with OS .46 AX's and lost mufflers have been a common theme. For this year the rules have been changed to allow the use of the Macs one piece muffler to alleviate this problem.

http://www2.towerhobbies.com/cgi-bin...p?&I=LXZ652&P=

Ken -

Another problem the OS mufflers have experienced is the muffler loosening up from the engine. When you safety wire the back half of the muffler to the front, it doesn't hurt to wire the front half to the cylinder at the same time. I've seen more than one OS muffler retained this way.

Hogflyer

G'day Mate,
This is true for all mufflers with through bolts, if the bolt is tightened, tight, as the muffler gets hot & expands, the bolt won't expand & it snaps, causing the loss of the rear end.
Only tighten em enough so the end won't rotate, then lock the nut down firmly, it will allow for expansion, & won't snap off.

Hogflyer,
I've never had a problem with the actual muffler coming loose. I use locktite on the muffler bolts so they stay in place. The problem with the back half of the muffler coming loose is because the bolt breaks. Once it's broken I will drill out the holes and put all-thread through the muffler to hold it together.

Ken

Safety wire? You can't show something like "that" here. We have liittle kids who are very impressionable, look up to you, imitate and respect you. Geeeese Looks like it's back to "Pick on Ken Day."

Cyclic,
Gee thanks!!! I was hoping everybody had forgot about that.

Ken

Yeah, we've been neglecting "Pick on Ken day" long enough.

Cyclic - New Avitar? I like it. Is that the model you flew?

As for Ken's all-thread mod, I do that to new mufflers instead of waiting for the bolt to break and have never had a failure.

Yeh.

Sweet bird. Could be fun, if you're not being shot at.

I saw a couple pictures and a description of replacing the bolt with a fully threaded bolt with a lock not on one end and two nuts on the other. Looks like a good set up. What size bolt did you use and what size did you drill the holes to? Did you use anything to keep these new holes leak proof?

Thanks!

Grab a length of 6-32 all thread from Home Depot or similar. Cut it to an appropriate length and put a nut on each end. (a second jam nut can be a good idea if you don't have a/c grade locking nuts). Leaks? We don't worry about no stinkin' leaks. Just drill each end of the muffler very slightly bigger so the all-thread just barely goes in. A #27 (0.144 in)drill is a good close fit.

What Bruce said!!!

Ken

I have lost two mufflers and a fuel tank in flight before. The first muffler fell off os 46 fx as the plane was at the top of a hammerhead stall. The engine stalled and the plane tumbled dead stick to the ground, surprisingly only about 10 minutes work to replace the damaged components but the replacement of the muffler took longer. the next muffler I had fell off of a ys63 as it was passing by me. It landed 30 feet in front of me on the runway. Unfortuneatly when the muffler fell off it weakened and wreaked the diaphram on the fuel regulator, oh well time to replace the diaphram. Latter on the fuel tank fell off my plane in midflight on a low pass. the joys of profile aircraft. now there was some embarassment and a need to find someone who had elastic bands

I've done some battle with keeping my tower hobbies mufflers together in the last few months.. I have the one for the .75 and I think that I have finally convinced it to stay on.. Went to Ace Hardware and bought a piece of threaded rod as close to the through bolt that came with the muffler.. (It will be a little bit bigger). Get two of these guys because you will destroy one of them getting this set up.. Take entire muffler apart, so that you have three pieces. Take one of your threaded rods, and thread it into the front section of the muffler. The metal is very soft, and the bolt itself will make new threads perfectly. Once you get it through, thread it back out and put your other threaded rod into the threads you just made, with about 1/2 inch coming through the front part of the muffler. Put a drop or two of RED locktite on the portion of threads sticking out of the front of the muffler and use 2 jam nuts to hold the threaded rod in place. Let this sit overnight. I needed two rods because the pliars that I used to hold the first rod steady while threading the muffler tore up the threads pretty good..)

Now, use High Temp RTV Silicone and attatch the center tube to the front muffler section. For the aft end of the muffler... Get a drill bit that is SLIGHTLY larger in diameter than your through bolt, and drill our the threads in the aft section of the muffler where the old bolt would come through. After you have that squared away, use more RTV on the center/aft joint and put the aft end on the muffler. You will have more threaded rod coming through the aft end, cut it off later.. Now use red loctite again, and double jam nut the aft end in place. I think with the threaded rod you can put it on a bit tighter without worrying about it breaking..

Lastly, get a few very small sheet metal screws and pin the front/middle/aft sections together with the screws...

So far no leaks, no turning on the back end, and most importantly its still on my plane!!@