I have a Bisson Pitts muffler on my DA50 and while flying my motor cut out... for those of you with a DA50 you understand how odd that is... Well knowing there had to be a problem I began inspecting my motor, plane, etc.. Nothing obvious... started the motor (first flip) no prob... then it was noticed my exhaust was shaking. Killed the motor and sure enough it was loose. Well upon further inspection I realize that the weld attaching the header to the pipe cannister was broken all the way around. The only thing holding that cannister on was will power. It is without question right on the weld. My DA doesn't vibrate at all. I'm just curious if this is a common problem with these mufflers or a freak occurance. Second, has anyone ever delt with Bisson cust svc? They are located in Canada and there's no way I'm going to ship this to them for right close to the cost of its original price... suggestions.... quick my plane wants to be flown!

Don

Shipping is not that expensive. I sent my muffler to them for a very reasonable rate. Get in touch with them to discuss warranty issues though; I told them my muffler was purchased used and they decided not to tell me that used mufflers aren't covered under warranty until I sent it to them.

what did you have done??? was it expensive???
I feel that this is a warranty issue for sure. Cool part about the internet... if they don't cover it under warranty EVERYONE will know about it!

Muffler ripped off just past the header. Pic in my gallery. It wasn't loose; fatigue just got to it. Couldn't be fixed so I had to buy a new one (at full price plus shipping). If they had told me ahead of time that used mufflers aren't covered under warranty, I could have saved myself time and money by just ordering a new one.

That's exactly where mine is broken! I only have 2 gallons through my DA though. Fatigue shouldn't be an issue.

I would suggest getting it in writing that they will replace it under warranty, then box it up and send it to them. Shipping to Canada is no big deal - under 'value' write $0.00 (which it is, since it isn't good for anything now) and shipping expense won't be much more than domestic.

That'll work, am I supposed to have a receipt??? I didn't keep it, who would have knew?

Don't know; if you bought it from them then they should have some record. If not, then they're probably decent enough to trust you. Just make sure you know exactly what you're going to get when you send it back.

Will do, thanks for the input.

Guys,

I'm sure that some of you have considerable experience with these mufflers but let me share mine with you. I have found that ALL of the manufacturers of this style of mufflers (pitts style) will break given enough time. I have adopted the policy of adding a supporting strap to the can that attaches to the engine to dampen the vibration. Some of the manufacturers give you a built in threaded boss to use for this purpose, most don't. Here's what I look for in a good quality muffler. 1. Welded construction- If you can't see real welding rod build up it's been dip soldered and will fail sooner than welded construction. 2. Built in boss for a strap on the can. If it dosen't have a strap I take it to the local weld shop and have one put on from the begining. I discontinued using Bisson due to their assembly process and no built in boss.
If Bisson isn't going to help you with warranty then gather up your broken parts and go to a shop that does TIG welding of aluminum, they can put it back together again. Be aware that TIG welding isn't cheap, if you get into a minimum charge then have a strap added or more of the joints welded.

Call Desert Aircraft - get their recommendation on a Pitts muffler -
they do have access to a nice one - I believe it is a Johnson - not certain/ As for vibration - your DA 50 viberates just as much as my ZDZ50 - this is not speculation - it is simply how these engines run - you can insure that all balance ignition carb adj is all correct but the POWER PULSES plus the inherant unbalance in all singles at about 3000 will induce vibes that can kill welds -if the muffler is not fully suported.
I have run the DA50-s - and they are excellent engines.
Your problem is not unusual nor peculiar to DA.
If you have a mounting boss added - be sure to mount the support to the engine-- NOT the firewall!

Does anyone have pics of a "mounting boss"? Would like to see just what it looks like. Also would like to print a pic to take to my buddy who welds. Thanks.

Sorry I don't have an pics of the "boss" I referred to. Surfing the net for the various manufacurers will yeild some results. Heres a description of what I am talking about. Slimline puts a threaded hole at the end of the can opposite of the header. You simply used a strap from a head mount bolt to the can and all was well. I assume they are still using this set up. When I have one welded on I simply form a piece of aluminum to the curvature of the can and have it welded on in the appropriate spot, drill a hole in end and connect a strap to it that connects to the engine. Also these things vibrate a buch simply because there is so much unsupported mass behind the engine. I always use lock nuts on the strap connections and saftey wire on all the bolts including the ones that hold the unit on to the engine, this usually takes some long bolts and spacers but is worth the trouble. It may still loosen up a bit over time but you don't have to go looking for the thing when you need to tighten the bolts.

I've run lots of Bisson mufflers over the years with no problems, so I don't think it's a common problem.

some of the larger ones -like the one for my zdz 80 have a mounting lug for a strap , not sure about the da 50 model but, as others have said u should use one.

shipping to Canada is not a problem! We are not on the other side to the world!

Bisson is probably closer than shipping to many area's of the USA

send it back , Jim Bisson has good customer service

sincerely,

Mike

Check out J&A Mufflers.

J&A incorporates the "BOSS" feature in Pitts style mufflers for engines 3.2 and above.

Well it's sent... we'll just wait and see what they do with it. I'm hoping for the best. It ended up being $10.00 to ship. I'm just upset that it had to happen before a long weekend. Oh well, might as well get the shop ready for winter building... besides my honey-dew list has gotten pretty good sized since the spring. Gotta love flyin' season!

Be prepared for a "long" wait. Canadian mail is one of the world's slowest. 12 days for my dad's birthday parcel to Ontario from Florida sent airmail. It's much the same in the other direction.

Gerry Rosebery

I just sent a new Bisson Pitts in that was on a hard mounted ZDZ50 for only 5 minutes run time...

I noticed some fo that "new engine black" on the muffler and upon closer inspection found a "micro" crack about 1/16 along the seem of the box...

Without a doubt a defect like this would result in a muffler breaking off... I could be the ones that fail sooner have these little weld defects, and are destined for doom....

I suggest checking it carefully after the first run for just such an indicator...

Question... will it do any damage to my motor running it without a muffler? yeah I'd be loud and annoying but would I see huge adverse effects?

i would not do it! your motor need the back pressure short run to tac rpm is fine but flying no

In Toole - who would hear it ?
anyway - the idle would be affected -but other than that - you won't hurt it - the noise is awful tho -
If I hear it in Murray - - I may ask you to put it back on --

LOL,

Thanks Dick. The forecast is for poor weather this weekend anyhow so I'll wait patiently. But I think I'm just going to give Dave a call and have him send me a Slimline next week. I'm kicking myself for sending it out now.

we may take over your field - the co----cker mayor of SLC got his lovlies to agree on a plan to take our field of twenty years -for another of the "needed multi sports complexes" .
we get an EQUAL facility as a fair exchange-- on top of a active landfill.
complete with seagulls -
this is no BS .

Where is that at? I really hate to hear about something like that happening. I've been out to the 23rd North airport a few times there are always quite a few people out there. That's going to be quite a dissappointment. It really sucks when you consider that the alternative to Rocky is Frank Pignanelli... Dick Hanson for mayer! lol

I am flying at the Tooele airport and Grantsville#2. I've never been out to #1 but from what I understand it's pretty much the same as #2.

We kinda met in passing a couple of weeks ago, you were talking to Pat in his shop and he and I talked a bit about the DA on my Edge having ignition problems. All's well with the DA now, runs so good it broke the muffler!

As mentioned in this posting these mufflers are not welded together. The process is similar to the aluma-weld solder method. If you attend some of the big shows you can find a guy welding beer cans together with this stuff. This works great for beer cans but for mufflers it eventually fails. Some break and others dont. If you want these fixed properly "TIG" welded, e-mail me. I have fixed to many to list!!