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Rotax exhaust manufacture
Posted: Mon Nov 26, 2012 11:44 am
by mulderpm
Hi all, the inlet cone assembly of my 180 deg side mount 582 exhaust cracked on both sides. Apparently, this happens with age.

The 90 deg inlet cone's do not do this. I am having it welded but want to replace it. The agents say that this component is no longer available separately and I must buy the whole exhaust, eina!

Does anyone know who can manufacture this tapered, tuned, pipe?

NB : this is not the small ball joint elbow.
Paul.

Re: Rotax exhaust manufacture
Posted: Mon Nov 26, 2012 6:08 pm
by Bundy
Have you phoned a few AP's and asked if they have a 2nd hand one?
How much does the Taliban's Extortion Programme want for a new one?
Call Alex Rudd....tell him what you seek my son.....

Re: Rotax exhaust manufacture
Posted: Tue Nov 27, 2012 8:12 am
by mulderpm
Bundy wrote:Have you phoned a few AP's and asked if they have a 2nd hand one?
How much does the Taliban's Extortion Programme want for a new one?
Call Alex Rudd....tell him what you seek my son.....

Thanks Alan.
New one, hold on.......R 4015.
After some searching I found the following:
De Graaf Silencers make exhausts and silencers to order.

mThey have made some for aircraft, even out of stainless steel if you want.

They welded mine and showed me a stock replacement, which they will fit if the weld does not hold.

I fitted the exhaust this morning and took AMH for a flight. No leak

. I think that is why the Taliban does not stock the cone separately. No one will buy it if De Graaf has it in stock at a fraction of the cost.

I did not ask them about a 90 deg bend cone, but I am sure they can make it.
So there you go....need an exhaust, who do you call...De Graaf.
Paul.
Re: Rotax exhaust manufacture
Posted: Mon Dec 03, 2012 9:14 pm
by nickjaxe
Read a scary tale on another forum the other day of a guy who mig welded his 2 stroke silencer...I think it was a 447....long story short....the engine somehow sucked in a piece of mig wire and destroyed the bore and piston.
Nick.
Re: Rotax exhaust manufacture
Posted: Tue Dec 04, 2012 10:03 am
by falconp1
You need to gusset the exhaust as shown. This is the only thing that ever worked for me.
Re: Rotax exhaust manufacture
Posted: Fri Dec 07, 2012 8:21 pm
by Boet
Have a nice one for you.

Check your PM.
Re: Rotax exhaust manufacture
Posted: Sun Dec 09, 2012 3:30 pm
by mulderpm
Thanks Boet for your offer.

Except for the crack the exhaust is still in good condition. My AP inspected the wall thickneses and gave it the thumbs up.
The gusseting method realy makes sense. Wonder why Rotax does not do this standard....oh I suppose then they wont sell any spare parts.

Re: Rotax exhaust manufacture
Posted: Fri Feb 01, 2013 12:45 pm
by mulderpm
Just come back from Van De Graaf who welded the Gusset on for me. I am sure she won't crack again with the gusset in place. Thanks for the great advice.

I will report if there is a problem.

Re: Rotax exhaust manufacture
Posted: Fri Feb 01, 2013 1:09 pm
by falconp1
Mine still going strong. I'm told the gusset dampens the harmonics which causes the cracking.
If you need to know more about the exhaust coating I can forward you the number.
Re: Rotax exhaust manufacture
Posted: Fri Feb 01, 2013 2:43 pm
by mulderpm
Thanks Falcon

She is coated with Aluminum....which I had to remove in the places where she had to be welded.

The flat bar gusset is obviously also not coated...so yes please, can I have the number.

Looking a bid shoddy with the cracks welded and now the gusset added to the ugliness.
P.S. what I find so strange is she has done in excess of 600 hrs, without cracking. She must be getting thin.
Enjoy your weekend

Re: Rotax exhaust manufacture
Posted: Fri Feb 01, 2013 3:39 pm
by falconp1
Had mine done by these guys. Cost me R1200-00 for all the bits (exhaust and manifolds)
http://www.google.co.za/url?sa=t&rct=j& ... JMyCyvYQ-Q
Usually if it wears to thin it blows a hole but doesn't crack. It would be a pity if you spend all this tom only to find that you have a recurring problem. If the people that welded the gusset on didn't have a problem blowing holes in your silencer then it can't be to thin. Just a thought.
Have a good one Paul

Re: Rotax exhaust manufacture
Posted: Sun Feb 03, 2013 3:21 pm
by mulderpm
Thanks Falcon. Those are the guys I heard about. Ididn't realise it was so expensive. I agree, before I spend the lute lets see if the gusset solves the problem on my exhaust. The guys that welded it did not have blow holes ! So maybe it is still ok.

Re: Rotax exhaust manufacture
Posted: Wed Apr 03, 2013 9:12 am
by mulderpm
25 hours later and no problems.

Re: Rotax exhaust manufacture
Posted: Wed Apr 03, 2013 10:04 pm
by bobthebuilder
My whole exhaust was repainted with a spray can. I think it was a Sprayon product. Not the crappy black gloss stuff, but rather a brownish colour ..... Yes a bit like crap I suppose.
Once sprayed, it is baked in an oven for some time. I did this three years ago, and it still looks like the day I painted it.
Your prep must be good though. The can was fairly expensive, around three hundred bucks if I remember.
I'll see if I still have some, and will post details if I come right.
Re: Rotax exhaust manufacture
Posted: Thu Apr 18, 2013 6:15 pm
by Poens Jacobs
Hi, Painted my exhaust with aerosol stove paint. Withstands temps of 700 degrees. Bought it at our local Mica Store. Price R90.00 Really works well.
Tends to burn away a bit at the manifold, but is fine on the exhaust!