View Full Version : Measuring humidity
11-11-2001, 07:07 PM
Fiddling with vintage cars, I just put together an engine that will sit for a while. The local hardware store had enough plastic barb fittings and vinyl tube to make a 'manifold' to all the enclosed volumes, after I machined and welded various adapters.
I plumbed the manifold to a plastic jar with desiccant packs.
Now, I'd like to see if all this effort was worthwhile. I once saw some paper strips that showed humdidity and would slip inside a 3/4" vinyl tube, kinda like the PH test strips.
Anybody know where to find the things?
11-12-2001, 02:28 PM
The only thing I know about would be something with cobalt chloride ( pink/blue ) which is used as a "used-up" indicator for dessicants such as silica gel and calcium sulfate.
IMHO, I would use a dessicant with an indicator and provide some air flow through the system. As long as the indicator indicates usable dessicant you should be safe. Although Silica gel is more expensive than calcium sulfate, the dust is probably less corrosive.
11-12-2001, 06:00 PM
I'm pretty sure that's what I'm looking for. Any sources?
BTW, I've got silica gel. Bought it in a 5 gal pail some time back. It's packed in paper 'bags' that look like they would contain any dust. It's also in a plastic jar, away from the engine proper.
I'd love to get circulation, but can't figure any way of doing it. I 'charged' the cylinders with argon from the welder and did the same to the sump as best I could. The ports will have to look out for themselves.
11-13-2001, 10:06 PM
What kind of motor are you working on? How old is it?
11-14-2001, 09:16 AM
What about an aquarium pump to circulate the air. You don't need a large air flow, just something to "sweep" the moisture into your dessicant. If you can't circulate the air another method would be to pass air through the dessicant then into your engine letting it escape through "poor seals" in the engine. Once you have achieved a good purge you wouldn't have to run it continuously. One supplier of indicating silica gel is www.gardenmedicinals.com (http://www.gardenmedicinals.com)
Also www.Midway.com (http://www.Midway.com) has it in "canisters" but they are more expensive.
[This message has been edited by rmatel (edited 11-14-2001).]
11-14-2001, 06:23 PM
I'll try both those sites.
Good idea on the pump; I'll see if I can figure a way to make it circulate.
11-14-2001, 07:04 PM
Hydrosorb (SP?) fills most of those little packets and all sorts of cans with disectant. I see them where the 400(rt) and I90 join just south of Buffalo NY and the local TV guy was there one day. But If you are going to do long term storage or store a few motors why not set up a drier (like for welding rod) to cook the moisture out? Say an old frezzer (lid on the top) with a light 40 watt light bulb?
11-14-2001, 08:13 PM
I use a 40 watt 240 volt bulb hooked up to 110 for my welding rod dryer. It gives off just enough heat to eliminate moisture and lasts forever. The one in there now has been on steady for at least five years. Could even build some kind of wood box and line it with plastic.
11-18-2001, 12:09 AM
As long as your bearings are not a pure babbitt you could just fill the engine with a high quality sythentic oil. I would contact firstname.lastname@example.org with a list of metals in the engine and known gasket types and ask them to recommend a proper fluid for storage. Amsoil Synthetics are highly ionic in nature and cling tenaciously to metal.
You have to remember that the dessicant may also react with metal and/or gasket/seals and dry them out.
Just a suggestion.
11-19-2001, 10:08 AM
I've tried filling them with oil, but most engines aren't designed to have oil above the plimsol line; they end up sitting in a puddle.
Interesting about the reaction with the desiccant. I'll check with the mfg about reagents.
Edit: Them, not then
[This message has been edited by Ron LaDow (edited 11-19-2001).]
11-19-2001, 10:31 PM
Amsoil has a chain spray safe for o-ring scooter chains that dries to a film that is also used as undercoating and protective film for long term storage. It is called Heavy Metal Protector and is quite reasonable. It may help in your situation but would require cleanup later. D-Limonene (citrus peel oil) would strip this tuff out like crazy (melts some plastics and is flamable) and is as safe as a stoddard solvent.