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View Full Version : Help With Hatori Muffler


carpman
10-05-2008, 10:57 AM
Just doing the final assembly of my 700, mounting the Hatori onto the heli, attached the brass pressure tap and it just spins won't tighten up :mad:

Took it out and it looks like it screws into 1-2mm of aluminium only, is this normal or should there be some backing underneath for it to bite into?

Not sure what to do now it holds and doesn't pull straight out but its not tight and I am a bit worried about it. What do you recommend, just glueing it in with any heat resistant adhesive I can find locally, not sure what I can find but I am sure I can find something...

I thought about dropping some soldering in and try and re-tap it, I'm no expert with these kinds of problems so any assistance I would be very grateful...

HeliSmith
10-05-2008, 11:39 AM
Can you put the screw back in and will it tighten up? Are the threads on the nipple stripped? I think this is a standard nipple.

I wouldn't want it coming off in flight...

carpman
10-05-2008, 12:13 PM
The brass nipple is fine the screw does the same, its the muffler the thread just doesn't tighten up at all, just spins...

HeliSmith
10-05-2008, 12:45 PM
Man... :(

I would probably go for JB Weld. Need some second opinions.

carpman
10-05-2008, 12:46 PM
Going to have a look in the local hardware shop see what they have, hopefully something similar to JB Weld...

Mercuriell
10-05-2008, 03:17 PM
Long setting epoxy - the 6-8 hr stuff is heat resistant and suitable though a bit hard to find - the 5 min stuff is a bit soft and more heat labile. The thread is M4 - I wonder if you have an imperial brass nipple eg 5/32" as that is just undersize enough to strip the thread. I'm sure JB weld would do - it's not super critical but a minor PIA if it comes off in flight - you always seem to lose the nipple!

carpman
10-05-2008, 04:05 PM
It holds in but does not tighten and I cannot pull it out, so hopefully something like JB Weld will give just that little extra to sort it out...

Failing that its a new exhaust or maybe trying to source a larger nipple and re-tapping the hole, however you do that ;-)

cbdane
10-05-2008, 04:52 PM
JB Weld will work great. You'll find at any auto parts or hardware store.

Oops, just saw Spain in your signature. JB Weld is a high temperature machinable epoxy for metal repair. I would think that you should be able to find a local equivalent.