jeff4912

Just got my 15cc gas engine from Evolution and they have redesigned the muffler to hopefully fix all the leaking problems it has been having.



It is a one piece design with no seams that I can see.

The pressure port for the gas tank has been sealed and there is not a bolt running through the muffler.

Exhaust is now straight out the back.

jstanton

My Feedback: (14)

I am thinking about getting one of these engines and doing some research on them. It looks like these is no tank pressure needed on the new 15GX. Have you run your yet and if so how is the new pump carb working for your?

jeff4912

Have not fired it up yet, but from everything I have heard and researched, it should be a great engine.

The only knock I had heard was that the muffler would come loose all the time and now that they have redesigned it, that should not happen.

I am building the airplane it is going into right now. Sig 4 Star 60

brones

Mine leaks like a sieve!

The 15GX2 gas (pumped carb) one piece muffler is leaking from half way down the muffler. I cannot see how to dissemble.
The manual shows a through bolt with a nut etc but my muffler looks to be a single peace with no nuts holding it together.
It is leaking from under the metal band half way down the muffler, the engine mount has sealed really nicely, so the gunk is not coming from there.
Do you know how to fix the leak? I am assuming I should be able take the muffler apart and seal, but I cannot see how to dissemble.

jstanton

My Feedback: (14)

Bones,

That is diffinitly a one piece muffler that looks like it had been press fitted together. I do not think you can take it apart. I would call Horizon Hobby and talk to their tech support and they my just send you another muffler. The muffler issue is why I choose to buy a OS GT15 gas engine. With the specials Tower is running right now I got it for 299.00 delivered. I have an NGH GT17 and have been fighting muffler issues with it for 6 months and did not want another engine that had these issues. Good luck with it and I think Horizon can help you. They have really good customer service.

Jeff,

Nice looking 4 Star 60. That plane is a great fly plane. I have the 4 star 120 with a DLE 20 and it is my beat flying plane. The Evolution 15GX should be a very good fit for your 4 Star 60

pilotpete2

I'm dissapointed to hear that the new muffler is leaking at the joints. I highly recomend the OS powerbox muffler that comes with the OS GT 15 as a replacement on the Evo 15. Looks and sounds good on the Evo/ 15.
Pete

Fwiw, it's not possible to cast a muffler like that in one piece

brones

I was hoping that was not the answer. I am in New Zealand, so it is easier said than done to get Horizon to ship a new one, might be cheaper for me to source a new one locally... not the ideal result after buying a brand new engine.

I was in a chat session yesterday with a Horizon product specialist, who to be honest had no idea what was going on, it was news to him that there were single piece mufflers out there. I have logged a call with Horizon, so it will be interesting to see what they come back with. I am picking either way I am up for a larger freight bill.

jstanton

My Feedback: (14)

Bones,

I chatted with Horizon tech support also and ask them if the new muffler had corrected all of the issues with the old muffler and he had no idea there was even a new muffler being used on the latest 15gx. That is why I decided to go with the OS GT15. I hope you can get your muffler fixed or even replaced by Horizon. It is a said thing when you have to go out and spend more money to get something corrected on a new engine

brones

After a week, Horizon have told me that the leak is pretty much normal operation, and I will need to ship the muffler to them for them to check... But disappointing from such a well known issue.

video of the leak.... Horizon, this is not normal!

http://www.youtube.com/watch?v=PL1XZkOXfPs&sns=em

jspauld2

Brones,

You are correct. I am sorry that someone told you that was normal, it definitely is not. I will get you in contact with someone to send you a new muffler free of charge.

Thanks,
Jimmy

brones

Support Request #132,733 and #133,163 they have just emailed to say they will send a new muffler out.

Ideally it would have not taken a week and half, 2 separate service requests, 2 web chats and 2 phone calls from New Zealand to USA... but hey at least I have a new muffler on the way, lets hope I can get my failure rate down from 100% to 50%

There appear to be many people not using the stock mufflers due to this issue, an idea might be to sell them without a muffler and we could use the discount to fund a decent 3rd party muffler??

I am really happy with the engine, it runs awesome.... but not sure I would buy another

jeff4912

Well...so much for the "re-designed" muffler.............



Was flying my newly built Sig 4 Star 60 breaking in the Evolution 15GX2 engine when I saw something fall off and the engine got very loud all of the sudden.

I thought, oh great! there it goes, I thought my plane was going to fall out of the sky.

Luckily the engine continued to run so I could land it in one piece.

The one piece muffler came apart at the shiny metal band.

Just ordered the OS E-4040 muffler.

Prior to coming apart, the muffler leaked like a sieve at the metal band.

pilotpete2

Ouch!!!!
Well, now it truly is a one piece muffler Jeff!
I don't know what they're using to bond the three separate pieces together, but the high temperatures, together with the oil in the exhaust are tough on whatever they used to "glue" the pieces together.
The OS muffler does use a through bolt, BUT, since the two halves of the muffler cannot rotate, due to the sorta square cross section of the muffler. I've been using the OS muffler for two years now, and have never had to tighten the through bolt
Y'know, since you have the pumped version, you might not really see any change in needle settings with the new muffler, since you're not using muffler pressure.
Let us know how you like the new muffler!
Pete

jeff4912

I will give you a flight report on the new muffler probably in a week or so.

Probably won't come the mail until mid-week.

Needless to say, that Evolution muffler was less than impressive!

jeff4912

Here is my remedy to the Evolution muffler issues.



Yes, that is a OS muffler on a Evolution engine.