muffle/exhaust 049

not found yet

It sounds like a nice project but I think, the link doesn't work for me, that you are referring to the Hiscott muffler. This is a rare item and, if you find one, will not be cheap. It was designed to be installed on the Cox Medallion 049

The only alternative I can think of would be

http://www.google.co.uk/imgres?imgurl=http://www.densmodelsupplies.co.uk/media/uploads/muffler_1292270355.JPG&imgrefurl=http://densmodelsupplies.co.uk/digest.php?view%3D35%26active_page%3D1&h=534&w=400&tbnid=2XBnnu9wfrouJM:&zoom=1&docid=zGne7Izl901oLM&ei=UAPQVOyrEMreao6HgMAG&tbm=isch&ved=0CCEQMygAMAA

or this and add a homemade muffler

http://www.google.co.uk/imgres?imgurl=https://i.servimg.com/u/f49/17/19/84/93/imag0514.jpg&imgrefurl=https://www.coxengineforum.com/t1195-wanted-muffler-for-049&h=475&w=800&tbnid=g-inxp2knAokgM:&zoom=1&docid=bWanm5zDGFNPbM&ei=4QHQVOmXMsbvaueXglg&tbm=isch&ved=0CC4QMygmMCY4ZA

These (if you are using a TD) may also need a spacer on the venturi.)

Which Cox engine have you dieselised?

i have a custom sure start diesel with heavy duty crankshaft
i have both exausts you show
but they but have problems
the 1sth one leaks becaus of the throttle ring
i can weld this shut but then i have to enlarge the opening to keep a good flow

the second is just sheit
i have no good words for it

and about the link your right the ) should be removed
http://www.mh-aerotools.de/airfoils/cox_3rdparty.htm

Ian.  The original link just requires the ")" to be dropped from the end to work.  I wonder whether a Cox exhaust collector could be used as a manifold to direct the exhaust into a "catch-can" type muffler.
 
These are pretty common & easy to find.  Ex Model Engines generally has them but they're currently out of stock.  The priming hole would need to be plugged, but a pipe could easily be attached to the outlet.
Rod.

Sorry, Robot797 posted as I was. If you're using a throttle ring then forget my suggestion.

Rod.

that is the point i dont want to have a trothle ring

but this exaust has one

http://www.google.co.uk/imgres?imgurl=http://www.densmodelsupplies.co.uk/media/uploads/muffler_1292270355.JPG&imgrefurl=http://densmodelsupplies.co.uk/digest.php?view%3D35%26active_page%3D1&h=534&w=400&tbnid=2XBnnu9wfrouJM:&zoom=1&docid=zGne7Izl901oLM&ei=UAPQVOyrEMreao6HgMAG&tbm=isch&ved=0CCEQMygAMAA

i also have one of those and i actualy do not want to modifie it (becaus it was expencive)

2nd PM sent.

There is always the Tatone muffler

Question: Do dieselized Cox engines with SPI cylinders suffer from the use of a muffler, like the glow ignition engines do?

roddie wrote:Question: Do dieselized Cox engines with SPI cylinders suffer from the use of a muffler, like the glow ignition engines do?

They do and for exactly the same reasons.

It also depends on what you call "suffering" - I have engines that were designed for use with a silencer and that silencer was developed with the engine. Some of these engines don't throttle happily without the silencer/muffler attached.

The introduction of the requirement for silencers killed the performance of many engines. SPI or not, added weight and ruined a previously perfect engine/model combination.

The Cox wrap around mufflers are not great and I have never been an advocate of throttling by restricting the exhaust.

If you are happy with reduced performance, for SPI and non SPI, the engine can still be set to run at a single speed. Throttling and SPI can be unsuccessful.

The addition of a diesel head to a Cox engine also brings additional problems. It also needs the venturi reducing or it glugs diesel like I drink beer. They run rich and this also compounds SPI and muffler issues.

In the strictest sense the Cox muffllers produced for the Bees don't muffle enough. They are still too noisy for such small engines to be allowed at most flying fields in the UK.

The Cox RC .05, .09 and the Queen Bee are passable. By far the best is the Hiscott/medallion 049 combination. All have no SPI.

Thanks Ian. You've answered quite a few questions that I had.

ian1954 wrote:There is always the Tatone muffler

Ian, I have one of those, bought it in the 1970's. I wasn't too happy with it as it was restrictive enough to reduce power significantly. I think the legacy Cox car engine muffler (photo provided by Rod) would have the same effect.


The annular ring Cox muffler isn't as restrictive, although it does cut some top end off.

Bernie's got an aftermarket he's designed and selling, which is reasonably priced:

http://coxengines.ca/cox-.049-muffler.html

There is a discussion here about muffler and Sure starts on diesel; RCU

Seems the already feeble Sure start engine will lose most of it's power....

A dedicated diesel, with muffler, would be much better to work with, such as the MP Jet .061 or one of the PAW engines (mufflers are optional for their smaller engines)

ian1954 wrote:There is always the Tatone muffler

that is one nice exhaust


the reason why i want an exhaust is becaus i want the fumes and oil to be collected in a diverent spot instead of the whole generator

Surfer_kris wrote:There is a discussion here about muffler and Sure starts on diesel;
RCU
Seems the already feeble Sure start engine will lose most of it's power....

Yes and no. Yes, it will lose some top end, depending on the muffler and amount of silencing required. In the video, I noticed the modeler was testing the engine, which had SPI. Cox made silenced engines had no SPI, to prevent dilution of the intake gases with inert exhaust gases.

The aftermarket Tatone muffler was more restrictive. I only used it a short time because of that.

Mufflers are a fact of life in many places nowadays. In that case, one then chooses their power needs. A muffled reed valve engine may be more appropriate on slightly smaller airframes/lighter airframes that can get by with less power. It's all about matching the available power to the right airframe.

GallopingGhostler wrote:
Mufflers are a fact of life in many places nowadays. In that case, one then chooses their power needs. A muffled reed valve engine may be more appropriate on slightly smaller airframes/lighter airframes that can get by with less power. It's all about matching the available power to the right airframe.

Yes, I'm aware of that and I do have mufflers on all my engines.
I thought the link on RCU would be instructional in terms of the power, and power loss, one can have.

In the early 80-ties I made my own mufflers for cox engines. The trick is to have a large volume and no restriction right at the exhaust port. Plus no SPI of coarse.

even that type of exauhst would fit my need

Surfer_kris wrote:Yes, I'm aware of that and I do have mufflers on all my engines.
I thought the link on RCU would be instructional in terms of the power, and power loss, one can have. In the early 80-ties I made my own mufflers for cox engines. The trick is to have a large volume and no restriction right at the exhaust port. Plus no SPI of course.

Wow, Surfer_kris, that is quite an engineering feat you have there! I call that 1) determination, 2) hardwork, and 3) success!

There is the cheap and cheerful way. Take a piece of aluminium tube, slice out a section in the middle, bend it around the cylinder and hold it tight with a nut and bolt.



Not quite but it does direct the exhaust! This was a standard muffler for DC engines.

that is awsome

that is whet i will try

That trick doesn't work on cox engines as the ports are larger/longer. You will not be able to seal the rear part, unless you use more than just the tube in that area.

ah crap that is to bad