fargophil

My Feedback: (3)

I have an old K&B 3.5 rear exhaust engine that has the exhaust ports on the muffler pointing straight up. Rather than get exhaust in my eyes when I start the engine I would like to turn the ports to the back. I removed the two little screws on each end cap in the body of the muffler but the end caps don't seem to want to turn. Am I missing something or are the end caps just very very tight in the muffler body?

proptop

My Feedback: (8)

I don't have one for the 3.5 but have a couple for the 6.5's and they are just a snug slip fit...maybe yours have some varnish sticking them together?

Might be some little burrs in the screw holes too...
I would try a little heat...just get it good 'n warm...then try turning them to work 'em loose (with a leather gloved hands) perhaps?

fargophil

My Feedback: (3)

Thanks for the tip. Tried it and still no turning.
I did do some online research and find that K&B/Mecoa shows three different mufflers for this engine. One with the vertical stacks I hav, one with stacks at 45 degrees and the final one with horizontal stacks. Beginning to think that even though there are screws at the end caps what you have for a configuration is what you are stuck with. Considering Mecoa wants $34.95 for the muffler with horizontal stacks, if it is in stock, I think Ill just be careful running the engine with the vertical stacks.

1QwkSport2.5r

Post a picture of the muffler you speak of. Anytime I see a muffler with a bolt going through it or screws holding it together I assume the muffler will come apart. Sometimes the machining fit is tight and lots of heat is the only way to make it budge. Just a thought.

aspeed

You could just make a 60 degree cut and bend the tip over a bit, or use a couple angled silicon extensions. Also flip it upside down, or remove the tubes, plug them and add a couple more.

Mr Cox

The ends should come off, I have one that is missing one end...

You could rotate the hole muffler (180°) and have the two outlets pointing down?
Or would that give you oil in the pressure line?

fargophil

My Feedback: (3)

hate to admit that the thought of just pointing the sack down had never crossed my mind. Kind of a forest for the trees thing.Dont think oil in the pressure line would be that much of an issue while flying but might drip after flight.
One other thought I had was to remove the screws holding the ends on and then run the engine and let pressure and vibration work in my favor.
Here is a picture I copied from Mecoa of what I would like to see, my muffler has the stacks pointing straight up.

Mr Cox

That's the one I have. The ends will come right off once you remove the two small screws that hold it in place. In cannot be twisted off though, it needs to be pulled or pushed, as it interlocks with a thicker part around the screws that holds it to the engine. So the first one is tricky to get off while the second one can be pushed off from the inside...

The ends can be placed in four different rotations, and would only require making the tiny holes and threads for the two screws.

fargophil

My Feedback: (3)

So if I were successful in getting the end caps off, I would need to drill and tap holes in the end caps for the hold down screws when the stacks are in the desired position?

Mr Cox

Yes, that's all it takes, at least on the version that I have.

jaka

Hi!
I also had the version my Swedish friend have shown you!
You have to ask yourself : How could they manufacture a tube formed silencer with end caps?? Either they soldered on or screwed on the end caps ...there are no other choices. As you have two screws ,there must be a possibility of taking the end caps off.