ChangFa R185 video w/stock and NAPA muffler

[europachris]

Hi, all.

Got around to making up some custom intake and exhaust manifolds for the R185.  Initial tests with mounting a Solberg 1-1/4 NPT thread air compressor silencer/filter on the stock manifold proved promising that it would reduce intake noise, but something still had to be done with the muffler.

I picked up a 'universal' fit NAPA muffler (fits a '87 Sentra) for about $27.  1-5/8 ID inlet and 1-1/2 ID outlet.  6" dia and about 15" long.

Picked up a chunk of 1-5/8" x .109 wall tubing and 3" wide x .125" strip from the local steel house and made up a intake and exhaust manifold and flanges.  It turned out pretty good for a first pass, and I'm a LOUSY welder.  Next time I'll have it TIG welded by a buddy.  That will save some grinding time....

I found a NAPA paint that matched the ChangFa paint pretty good for the intake pipe and used high temp aluminum paint for the exhaust.  Muffler is welded to the exhaust and there's a little brace that I welded from the rim of the muffler bottom to the horizontal portion of the manifold to help absorb the vibration.  Air filter is attached to the intake pipe with a piece of 1-1/2" ID radiator hose and two clamps, so it can flex a bit and take the vibration, also, which isn't bad at all.

Anyway, here are the videos:http://n9zes.zippyvideos.com/gallery.z

[edit:] It's not real obvious on the video, but the muffler did make a big difference.  The exhaust is just a low frequency PUFF PUFF PUFF sound now.  The problem is the mechanical noise of these ChangFa engines is louder than the intake and exhaust put together.  Overall, though, it's a big improvement and a worthwhile project!

There are also a few videos (for you diesel heads) of a Detroit powered snowblower at our local airport this past winter.  8V71 running the blower and a 6V53 running the chassis.  Sweet sound!

Enjoy!

Chris

[mjn]

Thanks for the videos Chris.  That is a nice compact setup you have.   Your muffler addition looks great.

[rgroves]

Hi Chris and thanks for the video posting

First thing, I REALLY LIKE the traditional wood rail mount on wheels.  Even a relatively modern engine like the ChangFa looks vintage when it's set up that way.
I don't know if that would calm the smaller models that lack counter balancing (I recently used a 175A as a gravel tamper, bolted to my timbers when I was building the engine pad) , but the 195 family seems made for that setup.

And yes even on the video I could tell a big difference in sound.  The engine still sounds like it's self-destructing    but the exhaust note isn't nearly as sharp as factory stock.  Can't tell much about the intake from this video but I have no doubt it's silenced nicely as well.

Very nice, and thanks again for the show and tell.

Russell Groves 

[europachris]

Thanks for the comments!

The setup really does make the engine quite smooth, but there's still a good bit of vibration.  I have the end under the generator sitting on some industrial machine leveling mounts (about 3" diameter) that damp some vibration, but it could use more.  It's actually better sitting on the grass as the dirt absorbs quite a bit.  You can't see the mounts as my grass needed mowing (that was today's project).

The intake did reduce the 'honk', but it was not huge difference (about 2dBa by the meter - from 97 down to 95dB! at 3 feet).  I didn't measure the exhaust, but it would be another 2 to 4 dB.  It's still at least 90dB.  Not something you want to sit by for any length of time like a Listeroid.

Nevertheless, it's a fine running setup, and amazingly smoke free once it's warmed up.  Even at full load (3.5kW) it doesn't smoke but the slightest haze.  Only if I idle it down and "floor" the throttle does it belch great black clouds (like an old Mack truck).

Chris