Blowing smoke?

[86rocco]

Something Bruce said about clear head fixtures in got me thinking, has anyone here used smoke so that they can observe how the air moves through their ports and into the cylinder? If so, did you find this to be a useful technique? What did you use the generate the smoke?

[Mousehouse1]

I thought about doing that but haven't tried it yet. Since I used clear deck plates, cylinder head fixture and front panel I should be able to see what the smoke does. Just haven't had time.

[bruce]

I bought one of those smoke generators you see around Halloween to use on my bench, it works ok but be ready to fill the shop up with smoke!! By necking the tubing down to a wand size you can get a nice little stream of smoke, I only used it a few times till I thought to myself whats this going to do to the inside surface of my pipes? Its packed away now . . .

I have found that a thin peice of string works much better and allows you a longer viewing time.

[Unkl Ian]

I've heard of people spraying Layout Dye into a port,
to observe the wet flow in the port.

[gofaster]

The Dykem tells you where the fuel drops out.

If you could come up with a way to mix the Dykem in a ratio representing a stochiometric blend of air and fuel it could be revealing. One caveat, Dykem is flammable.

Distilled water with food dye is fairly close to the sg of gasoline. If you use fluorescent dye, the mixture shows up with a black light.

[DaveMcLain]

I've used a pipe filled with tobacco to make a smoke generator and it worked pretty good, be careful because the pipe can get very hot quite quickly! I just get it burning and then use the mouth end to feed the port, it's somewhat useful but you need a bright light to see what the smoke is really doing in the port. It doesn't burn really very long and it fills the shop up with smoke(using some sweet smelling tobacco helps a lot).

[Ken73]

Has anyone thought of getting one of those little ultrasonic fogger devices, putting it in a tupperware tub with a top and running a tube from it? Have a hole in the top so air can get in and grab misted water or glycol or whatever and go through the tube?

[Tony]

A commercial smoke generator machine is one way, or even better still, build your own. They use an electric heating element and a special light oil that produces really dense smoke that has absolutely no smell and is completely non toxic. The fire brigade use this smoke for training exercises, and it is also used in stage and theatre. Different oil can be obtained to create smoke in various colours.

This special smoke machine oil should be available through companies that hire theatrical costumes, stage lighting and party hire equipment. A search through your local telephone book should turn up something. Just ask where you can hire a smoke machine, then just buy the oil.

For a source of heat, a hot soldering iron tip works fine, just dip it into the oil, and away you go. Or the oil can be sprayed or dripped onto a hot surface.

[Erik]

I think is hard to see where the smoke is going in the port and in the headstand when the test presure is high. I use a pice of thin string that is tie to a pin on the other end I will tie a knot and leave a pice so it will be frayed. Then you will se where it is going in the head stand and in the port.

[Ken73]

Just wanted to report - my ultrasonic fogger idea didn't work so well. Fortunately I'm not out any money for it though! I have an ultrasonic humidifier at the house that I borrowed to test the idea with; I taped a piece of sheet plastic (cut from a box of something else) to the hole on the top (where the misted fog normally comes out) and ran some flexible (aquarium) tubing over to an 1/8" tube and held it in front of one of my motors (since the flowbench isn't built yet.) I could see a tiny stream of smoke, but it's fairly useless.

I'm thinking the heated metal tin with tobacco or glycol in it would probably do a whole lot better. Not sure if a larger tube would do any better either.