We all know that the white paper/cloth doesnt do diddly to protect against water damage, and gaskets dont always work. I was wondering is there anyway to waterproof the mag without insulating it against picking up the charge from the magnet? electrical tape, jb weld, epoxy, silicon spray? I already sprayed mine with silicon spray, but is that permanent protection?
Waterproofing a mag?
- Thread starter bigbutterbean
- Start date
If your gasket is good, and you use some silicone sealer where the wires go in, then it should be waterproof.
Water proofing your windings is probably ok, but completely sealing the magneto coil compartment isn't good idea. When the motor warms up from cold there will be some condensation. The condensation needs a way to escape the magneto compartment.
Sorry, Biknut, I'll have to disagree here.
If everything is dry before you seal it up there should be no appreciable condensation to worry about. There's much more chance of water, rain or splashback, to get into the magneto compartment than any moisture in the air. I could see a situation where this might be true in very high humidity areas but even then, if the cover and wires are sealed there won't be enough wet air to get into the housing to be a concern.
The trick is to get the gasket mating surfaces flat and for the gasket to seal properly. Also using a silicone sealer around the wire entry area will assure that water stays out. There is no advantage to waterproofing the mag coil. In fact any product that might conduct electricity, even a little, will negate any waterproffing attempt.
Tom
If everything is dry before you seal it up there should be no appreciable condensation to worry about. There's much more chance of water, rain or splashback, to get into the magneto compartment than any moisture in the air. I could see a situation where this might be true in very high humidity areas but even then, if the cover and wires are sealed there won't be enough wet air to get into the housing to be a concern.
The trick is to get the gasket mating surfaces flat and for the gasket to seal properly. Also using a silicone sealer around the wire entry area will assure that water stays out. There is no advantage to waterproofing the mag coil. In fact any product that might conduct electricity, even a little, will negate any waterproffing attempt.
Tom
Well, you could be right Tom. I don't think it's a big problem either way. A lot of people seem to think moisture is killing their magneto coils, and it may play a minor roll, but I think the way the stock kill switch is wired is the real culprit.
I dont use the stock killswitch. I have my own toggle on/off switch, wired to the black and blue wires from the cdi. I have burned up 3 magnetos due to water getting in. Every single time a mag went bad on me, I would take the mag cover off and an exorbitant amount of water would drip out. Does silicone spray permanently waterproof? I sprayed the windings with it already, when I put a new mag on last time.
I contend you are probably burning up your magneto coil windings with your kill switch.
A better way to wire it would be to run only the black wire through the switch.
Run the black wire from the magneto coil to the switch, and then from the switch to the CDI.
No need to run the blue wire to the switch. When the switch is closed it runs. When the switch is open it kills it. That's opposite of the way the stock switch works. The stock switch closes when you push it, and shorts the black and blue wires together.
That could be true, except for two things. One, I just installed this killswitch, and for awhile I ran without a killswitch at all. I also ruined a mag when I did not have a killswitch. I also did not have a proper magneto cover gasket at the time. I also did not post this thread to debate why my magnetos went bad. You may contend all you like, but it will not change the fact that as far as I can tell, they went bad from getting wet. The white paper around the windings also changed to a rusty color after they got wet. So I'm done debating the killswitch theory.
So currently I am theorizing that silicone spray is sufficient for waterproofing a mag. I sprayed that stuff on my mag a good month ago at least. Today, I went to open my mag compartment, and when I loosened the screws, water dripped out. It had rained last night, and I thought it would be ok with the gasket I put on there. So anyway, normally when I do get water in my mag compartment, the paper covering the mag turns to a rust color and the engine wont fire. This time, the paper was still white, and the engine did fire up for me just fine. So perhaps the silicone spray is a permanent waterproofing solution, because its the only thing different from my other mags before they got wet. So I just thought I would share this.
Maybe you should consider covering your bike with a tarp. Why leave it sit out in the rain? Even a plastic trash bag over the engine would eliminate the problem.
I still submit that you have not sealed the gasket or wire entry opening at the front of the case. If those two areas are well sealed there is no possible way for moisture to get to the magneto. Remove the cover and lay a sheet of sandpaper on a flat surface, run the cover gasket surface down, against the sandpaper and check to see if it is uniform across its surface. I've seen them warped and would leave a gap even with the gasket installed. Run a bead of silicone on the cover and reinstall.
I inject some silicone into the wire port from the mag side and from the front. Never had a drop of water get in.
Tom
I still submit that you have not sealed the gasket or wire entry opening at the front of the case. If those two areas are well sealed there is no possible way for moisture to get to the magneto. Remove the cover and lay a sheet of sandpaper on a flat surface, run the cover gasket surface down, against the sandpaper and check to see if it is uniform across its surface. I've seen them warped and would leave a gap even with the gasket installed. Run a bead of silicone on the cover and reinstall.
I inject some silicone into the wire port from the mag side and from the front. Never had a drop of water get in.
Tom
Briggs engine had on my old cast iron 5S so much glue goop over point cover (the magneto just under flywheel cover only), then when I need to access the points I was there forever with exacto knife.
I have not had a problem with a briggs magneto but it does seem to have a clear coat of some kind on it.
I had made rc models where with non-waterproof expensive servos, I used some think it was krylon clear coat epoxy spray paint. That seemed OK but then went a used stuff like dip it, stuff for replacement grip on hand tools. This is probably too thick a coat for your purpose.
That last stuff seemed to be like back at school where when making a choke (inductor) we wound our own magnetic wire with that very thin shellac insulation magnetic wire, and then bound it up with a clear or amber stuff of sort dipping it to have it not be affected by vibration or moisture.
Funny, but sad too was some guy sees me using a screw driver putting it in the live solder iron temperature adjuster testing instead with light bulb. I was only using various series parallel combination and felt it quicker not to use a wire for the various combinations of connections. Instead I contacted on the metal part away from the plastic handle to make electrical connections. The coils everyone made were not exact the same micro henry so the capacitor needed to compensate I was figuring out this way.
The guy takes a screw driver himself and I see him like wrenching the thing back and forth in the project we had to build. Sparks were flying!
He was not hurt, but I got to think he had better have not had this as his major.
MT
I have not had a problem with a briggs magneto but it does seem to have a clear coat of some kind on it.
I had made rc models where with non-waterproof expensive servos, I used some think it was krylon clear coat epoxy spray paint. That seemed OK but then went a used stuff like dip it, stuff for replacement grip on hand tools. This is probably too thick a coat for your purpose.
That last stuff seemed to be like back at school where when making a choke (inductor) we wound our own magnetic wire with that very thin shellac insulation magnetic wire, and then bound it up with a clear or amber stuff of sort dipping it to have it not be affected by vibration or moisture.
Funny, but sad too was some guy sees me using a screw driver putting it in the live solder iron temperature adjuster testing instead with light bulb. I was only using various series parallel combination and felt it quicker not to use a wire for the various combinations of connections. Instead I contacted on the metal part away from the plastic handle to make electrical connections. The coils everyone made were not exact the same micro henry so the capacitor needed to compensate I was figuring out this way.
The guy takes a screw driver himself and I see him like wrenching the thing back and forth in the project we had to build. Sparks were flying!
He was not hurt, but I got to think he had better have not had this as his major.
MT
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When you seal the mag correctly, you can cross rivers that have your mag below water level with no problems.
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That interesting that you mention that as I saw a while back an old surface / underwater scooter. This is the kind for snorkeling or scuba diving. It was not an electric motor, but a 2 stroke gas engine type. On the surface it had use of a snorkel for air intake. Underwater there was an attachment to go to the intermediate pressure on the first stage port of the regulator on the air tank (90psi) which is being used also by the scuba diver to breathe under water.
They must have had a good seal somehow for all of necessary places to keep water out, but it was used and being sold and may have been 2nd hand used.
I was tempted, but ended up on an electric type.
Saw also the Danish Navy on Discovery Channel ages ago where frog men go out a submarine under water and bring with them an inflatable boat along with gasoline engine. The boat inflated as a few tended it to the surface. They unplugged intake and exhaust at the surface and started it up and got underway at night speeding across the surface. They had a guy with a large ring over the side for other frog men that had spread out to keep cover with guns for the ones prior assembling the boat. The ones in the water grabbed the ring and got hauled in at quite a fast speed. The a few more hauled in and they went off into the night.
If I can get a fish covering over my motor bike maybe I can set up an extra air tank with valve for the engine dedicated for the motor bike / art fish mobile underwater and see if I can go diving incognito.
MT
I came up with a better idea than the silicone spray (being as I don't have much left, and I'm not sure that I could cover the entire gasket with it). I know that paint is usually waterproof, and I have almost an entire can of spraypaint that I didnt use, because after I sprayed it I realized it wasn't the color I had wanted. So I'm going to paint the gasket with it, and also give the mag another coat of silicone spray while I'm at it.
I just finished painting the gasket with rustoleum gloss protective enamel. I stuck it on some twist wire and sprayed both sides of the gasket until paint dripped off profusely, then hung it on a hook outside my back window to dry overnight, so I can put the gasket back on tomorrow. I also shot the mag with another coat of silicone. I figured while I had the cover off, might as well give it another coat of silicone, just for added protection. I let the silicone dry while I painted the gasket, then put the cover back on and put a plastic bag over it just in case it rains overnight.
Yea Krylon Paint in spray can is what I used for the servos, but first put tape over the servos first.
If there is any chance that the paint is such that it could attack the shellac or whatever is that very pretty much clear or amber cover is on the magneto windings and if it could make them short out, that would not be good!
If you have an end to the wire from the magneto where it is not part of the windings and still has the shellac thin coating that it came with, and then you could mask everything but that small part of the wire and see if it is OK first. If the thinner that cuts the spray paint adversely affect the coating like bubbling I would have to say try something else.
A lot of ideas at these links
Seems that a name came up McMaster Carr and the stuff that is called room temp. cure 2-part unsaturated polyester that is used if you don’t have vacuumed and oven or send out to shop for expert …. On the flip side some people actually used Minwax polyurethane
http://bbs.homeshopmachinist.net/archive/index.php/t-15698.html
http://en.wikipedia.org/wiki/Magnet_wire
MT
If there is any chance that the paint is such that it could attack the shellac or whatever is that very pretty much clear or amber cover is on the magneto windings and if it could make them short out, that would not be good!
If you have an end to the wire from the magneto where it is not part of the windings and still has the shellac thin coating that it came with, and then you could mask everything but that small part of the wire and see if it is OK first. If the thinner that cuts the spray paint adversely affect the coating like bubbling I would have to say try something else.
A lot of ideas at these links
Seems that a name came up McMaster Carr and the stuff that is called room temp. cure 2-part unsaturated polyester that is used if you don’t have vacuumed and oven or send out to shop for expert …. On the flip side some people actually used Minwax polyurethane
http://bbs.homeshopmachinist.net/archive/index.php/t-15698.html
http://en.wikipedia.org/wiki/Magnet_wire
MT
