Video of Properly Running Atomic 4

[Charles Taylor]

Don,

Which of your videos would best show a properly running Atomic 4? If they don't maybe you or someone could record one and post it on the site. Many of us are probably chasing our tails by trying to fix sounds that aren't broken.

Thanks,
Charles Taylor

[Don Moyer]

Charles,

Our ignition video contains scenes near the end where we are running an engine on a bench. I'm not sure if it will serve as a reasonable base line of sound for you or not. The engine actually sounds quite good.

Don

[Kelly]

Charles,

I have a video at home of a bench test of my A4 that I will try to find and post on the net.

I'll let you know if I find it and where to go to see it.

Kelly

[Administrator]

I think there are a least a couple of videos on YouTube. Search for "Atomic 4".

Bill

[CalebD]

Fixing sounds that aren't broken

I found 5 videos on youtube with short videos of A4 engines being run. The sound will always be somewhat different when the engine is mounted in its compartment on a boat. Most of the auido of the running engines reminded me of idling tractors.
This one reminded me most of the sounds that our engine makes at idle: http://www.youtube.com/watch?v=-JyKYvQw2dM

[marthur]

Charles,

If you are still looking, I just posted a video about using the hand crank that has an A-4 running at the beginning and end.

http://www.youtube.com/watch?v=ntUkgUXM0-o

Mike

[Kelly]

Mike,

Nice video and explanation. Thank you for posting them.

Kelly

[sastanley]

I realize these are unmuffled motors usually running on a wooden stand, but I think mine sounds pretty good when comparing!

So...how long can you run the motor without cooling water? I noticed one guy seemed to have a bucket for exhaust, but most of the others were likely not being cooled?

[Baltimore Sailor]

Here's a video of my A4 running. The noise you hear at first is actually the blower motor; it must have resonated through the deck where the camera is sitting, because it doesn't sound that loud in real life.

Unfortunately it cut off a little earlier than I wanted to, but you can at least see the tach reading 2000 rpm and hear what the engine sounds like. This is with the tranny out of gear. Doesn't that 2000 rpm sound a bit like it's over-revving? Is that REALLY 2000 rpm?

[GVIDEO]http://video.google.com/videoplay?docid=-1886630391290424624&hl=en[/GVIDEO]

[Kelly]

Very interesting. You say that the engine is out of gear but I hear a definite "whirring" or "whining" that I don't get from my engine when it is in neutral.

If you listen to this engine on You Tube -not mine- (YouTube A4 Running) you'll have exactly what mine sounds like. Note the deep "tractor" sound and the change in pitch when the engine is revved. No whining.

This You Tube engine is not muffled and I don't think it's revved to 2000rpm but even in the boat, you still get the tractor "popping" sound that smooths out to an aggressive purr at higher rpms. To me, and others will hopefully pipe in, the sound coming from your video is quite different.

Kelly

[sastanley]

Balt. Sailor,

Our engines sound very similar..I get the whining too, I think on my engine it is because the 'neutral spot' is so small...If I set the gearshift so there is no whine, the prop is slowly spinning in forward.

I slapped an old tach onto the motor, but the leads were only about 24" long, so I had it taped down below, and couldn't read it from the cockpit..before I had the prop cleaned, I could only get about 1,200 RPM, but it sounded like it was racing when out of gear around 2,000 like yours! I've since purchased a new tach, so I am gonna plug it in and see what I get..I think the old tach may have been dropped on the garage floor one too many times.

I can't imagine what it would sound like at 3,000 rpm if it ever got there!

Thanks for posting the video..I can get to google videos at work, but you tube is blocked, so I can only watch those at home. I'll try to get to the boat this weekend, get my tach in and maybe shoot a short video myself, before hauling for the winter.