Post if your magneto failed due to moisture

[Wickedest1]

Thats what I normally do and I think when my new mags come in some time next week I'm going to have to seal it ...my gasket was broken and water did seep into the case causing it to short out improperly...I'm still hunting for instructions on how to rebuilds the mags...hopefully we dont get any more really crappy weather...I'm dying to cruise...and I have cut the silencer canister from my exhaust..i lose a little bit gas mileage wise but the increase of power is insane...i recommend you check local decible laws for motorized exhaust systems before you cut it off...loud pipes save lives...

 

[moonerdizzle]

loud pipes piss off cops. pissed off cops makes life hard for the rest of us. also, if your exhaust is straight piped, unless its a four stroke you will burn up your motor.

 

[bairdco]

i fixed a guy's bike a while back 'cause it wouldn't start. he left it in the backyard for months, and when i opened the mag cover up a ton of water drained out (same with the clutch cover.)

i took the mag out, sprayed it down with carb cleaner, cleaned the moldy water out of the case, and redid all the wires by unsoldering them at the mag and resoldering new ones on, and replaced the ground lead, too.

used heat shrink tubing over the connections i soldered to the cdi, and then a bigger piece of heat shrink over both wires from the inside of the mag all the way to the cdi (through the grommet.)

also scraped the epoxy off the mag where the ground lug goes.

with fresh gas the bike fired right up. it's been at least 6 months and i saw the guy the other day. still going...

i've ridden in the rain plenty of times (not by choice ) and haven't had a problem.

that being said, i've had a few mags die for no reason at all. some are crappier than others.

i think good wiring is key. cut off the crappy butt connectors and solder the wires together, and heat shrink it all up. less problems and a cleaner installation.

 

[bairdco]

here's what my wiring looks like..

 

[Wickedest1]

@mooner yes loud pipes do piss off cops...but i live in an area where there are a lot of elderly drivers and have actually been hit 3 different time riding my bike with the silencer canister on...i checked into the decibel laws here in Connecticut and am way under the db ratings for exhaust pipes...i got 2 new mags and keep one in the tool bag i ride with...i put a dab of silicone on the solder points of the mag and it seems to be ok...my mb is running great except as of my recent ride the screw that holds the pinion gear in place blew a hole in my crank case cover...and its missing...got an ngk spark plug from napa auto parts and man the difference is insane...

 

[crassius]

Has anyone tried painting the coil to seal it against moisture?

 

[Wickedest1]

Yes my last mag I painted with flat black paint...it still failed...plus the copper core is plastic coated from the factory...I've heard permatex from a few back yard motorcycle mechanics...I've never tried that becauseits more expensive than paint...

 

[wheels6942]

Hey, I wonder if you could polyurethane it?

 

[BoDean_LP]

My gasket ripped up when I opened the mag cover one day and I have yet to replace it. The mag quit on me recently. When I opened the cover, water just poured out. When the bike quit firing, I thought it was surely the CDI that had quit, because the headlight still lit up when I turned the motor over, but I wasn't getting any spark.

I tested the mag, and the white wired had voltage, but not the blue one. I unwrapped the mag to find that the tiny copper wire that connects to the blue wire's output post had broken connection. I couldn't get my soldering iron to heat up, so I just stripped the coating from the tiny copper wire about an inch back, and just wrapped it around and around the post. Then I rewrapped the wax string to hold everything in place, and finally wrapped all of that in masking tape.

When I reinstalled the "franken-mag", the bike fired on the first release of the clutch. Choked the carb, and she fired right up and runs good. I wonder how many mags have had this issue?

I'll eventually UNWRAP all of that and actually solder the wire IF the mag quits again, but with as much as I wrapped that wire, I doubt that'll be necessary.

 

[MEASURE TWICE]

I have a 70's era briggs engine 808202 0430 3hp 4stroke and the mag is just under the flywheel cover which is not like the points that have rtv or goop to seal it. There is no real gasket other than if your slobber it all around the cover for the points and the area wires feed inside cover.

The only time I ever had a problem with the connection was not soldering of wires as they only crimp them on what I got, it was myself that was moving one of the wires when working on the engine that broke it.

They just have a sleeve, not heat shrink over the very brittle magnet wire and no strain relief at all. There are 2 wires that are solid and 1 stranded. One of the solid wires must have had too many times moved and in the 40 plus years since mfr became brittle and broke.

Oh right where the solid wire went into epoxy it cracked off. I used and old solder iron tip and melted the epoxy around where a little copper dot was all that was left. I got around a 1/4 inch of coated magnet wire exposed. I scraped the insulation off the wire with an exacto knife and soldered a wire and heat shrinked it.

The extension wire I added was this very flexible high temperature / high voltage wire that I got at Radio Shack. I high temp rtv'ed it all over as a strain relief and works great now.

The kind of kit engine type you are mostly using here with the moisture problem I have to wonder if the water corrodes the solder connection and then it loosens. There is heat shrink as mentioned after removing solder and doing a better job than original and that make sense for sure. Making the cover seal better is also good.

Only think I can then add it that if you used the heat shrink that you ask specifically for at a Marine Supply Store, make sure it is the kind that not only shrinks, but has a shiny inner coating that melts like a glue and seals the ends of the heat shrink around the wire.

An old salt up there by Whidbey Island, WA had mentioned this and later I find it available in most big cities at West Marine dealers. The price is like 5 times the price for small packages, so maybe someone knows of a better way to get the stuff I’d like to know.

http://www.westmarine.com/webapp/wc...ngId=-1&searchKeyword=heatshrink#.UKb7mWf4Igo

The stuff is


ANCOR MARINE
Adhesive-Lined Heat Shrink Tubing (ALT)

MT

PS

It almost seems that a new engine should be suspect for this and just done over regardless if the mag fails so you not walking home to do it later.

 

[Tool Maker]

There are two threads active here about failed magneto coils & water. After reading both threads it appears that the failures are both mechanical & electrical in nature.

I don't have a "china girl" to dissect, but it sounds like the coils are "just good enough" like a lot of the other parts. If a coil is not bonded or impregnated when it is manufactured, engine vibration will eventually kill it. Mechanical failures often turn up at the worst moment, and can be mistaken for other issues.

I noticed that at least one person has had success with simply drying the coil. I have dried out plenty of electrical equipment that would pass High-Pot testing after drying. Sometimes there is enough crud in the water that when it dries it leaves behind conductive deposits - and the coil will fail high voltage testing even if it checks with an ohm meter. We rinsed things like motor windings in distilled water before drying to help with that.

The best answer is to keep the water out in the first place. Good coils are completely encapsulated or "potted" like Briggs, and others. A Homelite 360 chainsaw has a very similar system to the china girl, and it will run almost completely submerged - as long as the air cleaner is above the water.

Without having a coil in front of me, I can only guess what they are made of or how to improve one. If anyone has a failed coil they want to send me I would be happy to High-Pot test the insulation, and look at the failure. It seems like there must be a better solution than replacing them on the side of the road & carrying a spare.

B.

 

[wheels6942]

Where do you want me to send it, lol? Mine just went out, I just got the replacement, and, yup, I'm carryin' a spare. Also bought a 3rd to experiment with coatings to see if I can get something to work

 

[wheels6942]

I was thinking polyurethane, but not sure about working temps.

I've noticed a few people talking about the magnetos going out and cdi/spark plug/wiring upgrades in the same post.... mine blew after I put a new wire and plug in (e3.10)..ran frickin awesome......til it didn't. Of course, that trip to the car wash probly didn't help,lol. I thought everything was sealed up good and I tried to be careful, but evidence points the other way. Live and learn.

 

[Tool Maker]

Wow, that was quick! Thanks Wheels, I will PM you an address.

B.

 

[wheels6942]

Yeah, I've been haunting the forum for the 3 or4 weeks since I got my chinagirl. I finally got it dialed in and then this, lol.

 

[MEASURE TWICE]

There are two threads active here about failed magneto coils & water. After reading both threads it appears that the failures are both mechanical & electrical in nature.

I don't have a "china girl" to dissect, but it sounds like the coils are "just good enough" like a lot of the other parts. If a coil is not bonded or impregnated when it is manufactured, engine vibration will eventually kill it. Mechanical failures often turn up at the worst moment, and can be mistaken for other issues.

I noticed that at least one person has had success with simply drying the coil. I have dried out plenty of electrical equipment that would pass High-Pot testing after drying. Sometimes there is enough crud in the water that when it dries it leaves behind conductive deposits - and the coil will fail high voltage testing even if it checks with an ohm meter. We rinsed things like motor windings in distilled water before drying to help with that.

The best answer is to keep the water out in the first place. Good coils are completely encapsulated or "potted" like Briggs, and others. A Homelite 360 chainsaw has a very similar system to the china girl, and it will run almost completely submerged - as long as the air cleaner is above the water.

Without having a coil in front of me, I can only guess what they are made of or how to improve one. If anyone has a failed coil they want to send me I would be happy to High-Pot test the insulation, and look at the failure. It seems like there must be a better solution than replacing them on the side of the road & carrying a spare.

B.

I think that since the windings of the mag may be suspect for inferior coatings that could make them short out under vibration, maybe they would still work when dry, but not when wet.

If one was to add additional coating to a dried out coil, the coating may or may not actually get to where the mfr's initial coating insulated the windings have their coating rubbed off and is then still shorting.

If windings are already shorting internally in the wrap of windings there is little chance that insulation can be put back. The short would then still be intermittent with vibration. Adding another exterior covering over the coil directly or making a better seal on the case could keep out moisture, but if you can’t get to a winding near the center of the windings and insulate a short, vibration intermittent will most likely still occur.

Warranty still may not be so good as the replacement part may just have the same thing happen again. Sorry to hear all these similar problem with mags and wonder in there are aftermarket parts that are any better and are universal fit?

MT

 

[Trevorsking]

Yes I believe I am one of the people you are talking about.

I had to leave my bike out during the Sandy storm because we had guest and the wifey put her foot down and wouldn't let me keep my toy in the house (no garage)

My first indication was when I started my bike up the throttle response was very sluggish and I had to keep applying throttle just to keep it running. My first thought was moisture in the gas so I flushed (with gas) the tank, line and carb and dried it out good by towel and then letting it sit over night.

I put new fuel in the tank and tried to start it and I barely got it to fire at all and wore myself out in the process. I had a new CDI and spark plug at the ready and swapped them out, ensuring that I cut the spark plug cable back an inch and reseatingscrewing the ends in the cap and CDI. Again I got hardley any combustion when trying to start it.

So that led me to remove the magneto cover and there was fluid in there, not alot, but enough. It appears that rain water flowed down my wires and went through the hole that I had put silicon in. Guess I didn't do a great job with that, but **** you can't pressure test it. While I have had it down, I went ahead and put new piston rings and head gasket on it. The bike was running great but I did notice on two particulary steep hills near the house I was losing power so I had bought those to put on at some point, I tried to get it running again after taking the wifey's hair dryer and dried up the wound coil assemby and the protective wrap. I still have the same issue as before, so I guess my only alternative is to now order a new mag coil and hope and pray thats the problem. I have tried 3 different spark plugs that I had bought to have on hand just in case ( so much for me stockpiling replacement parts, I live on the east coast and shipping takes forever or I pay more for shipping to get it in a few days, than the parts themselves) maybe I should open a parts site for us east coasties.

Anyone have anything else I should try, Oh by the way I did and still have the kill switch unhooked. so thats not it (my first lesson and advise after my build to get it to start on my maiden voyage. My bike has about 1500 miles on it now, I ride it to work everyday and I built the bike back in late june or early july 2012. I need to get it back on the rode ASAP. The only bennie is that I was finally able to take the time to do the piston ring job and put on my manic mechanic rear hub sproket assembly with a 40 tooth sproket, but I can't check it out to see if the rings helped and the new hub assembly was worth the money. I think just the 40 tooth sproket while help me get above 35mph, which will be nice.

Just in case you need the info:

66cc megamotors from Bikeberry, NT carb with factory WOT jet ( I have a 68mm and 66 mm jets that I was going to play with, but haven't had the chance yet), Autolite 275 spark plug (tried the NGK, but my motor seems to run better with the 275), 415 chain, 40 tooth sproket, new clutch (about a three weeks old), fuel to oil ratio ( 4 oz to a gallon). Idle screw backed out 3 and a half turns after fully tightened (idles great normally).

I tried a multimeter check that someone had posted and I get nothing from blue to black, aLthough the white wire( which is isolated) reads 24 ohms.

Does anyone think it could be the woodruff key on the magnet shaft, would that make sense and I heard that the magnet removal is about 50/50 (another post I read), so I don't want to try to remove it unless I have to.

Ok I wrote a book, any suggestions or something I missed from my checklist, please respond, even if it is just a vote of encouragement, I am getting frustrated and the wife ain't helping. I spend to much time and money on my bike (she is just jealous I think

Thanks,

Ron (Trevor is my son, and he is king around here)

 

[Trevorsking]

Ok just did the ohms test again, nothing from blue to black. white to ground was 2.4 which is within the specs I have read from Norm I think. I also went old school and did the light bulb test with a new 12v bulb for my truck. No spark at the spark plug nor after the CDI and again nothing after the coil bundle

 

[MEASURE TWICE]

i fixed a guy's bike a while back 'cause it wouldn't start. he left it in the backyard for months, and when i opened the mag cover up a ton of water drained out (same with the clutch cover.)

i took the mag out, sprayed it down with carb cleaner, cleaned the moldy water out of the case, and redid all the wires by unsoldering them at the mag and resoldering new ones on, and replaced the ground lead, too.

used heat shrink tubing over the connections i soldered to the cdi, and then a bigger piece of heat shrink over both wires from the inside of the mag all the way to the cdi (through the grommet.)

also scraped the epoxy off the mag where the ground lug goes.

with fresh gas the bike fired right up. it's been at least 6 months and i saw the guy the other day. still going...

i've ridden in the rain plenty of times (not by choice ) and haven't had a problem.

that being said, i've had a few mags die for no reason at all. some are crappier than others.

i think good wiring is key. cut off the crappy butt connectors and solder the wires together, and heat shrink it all up. less problems and a cleaner installation.

=========================================


From: Measure Twice

To: Trevorsking

Did you try the bit about remove solder and re-solder wires where Bairdco mentions in a previous post?

I quoted so you can see it above!

Hope you can get it running what ever it is! If it turns out you can have it reliable and running with out any more cost than using a solder sucker first and then add new clean solder and a few watts of energy to melt it, that is a good thing. Hey but you get it running

Measure Twice

 

[Trevorsking]

hey measure twice,

Yeah I resolder everything and throw out all the electrical connections that come with the kits. This always saves time down the road and eliminates those things from troubleshooting later (but I do take a look at the soldering to ensure it hasn't been compromised from vibrations.)

I went ahead and took the magnet off the crankshaft and inspected the seal behind there and it looks good (also to be sure that it wasn't the source of the moisture), I know it has nothing to do with it not starting unless it is damaged bad enough to cause an air leak. I also inspected the woodruff key and it is good to go. I ordered another magneto coil today but it won't be here for several days due to thanksgiving. I think while I have the time I will strip the sealant off the coil and inspect the inner connection under it just for fun. I REALLY DO LOVE WORKING ON THESE MOTORS, THEY ARE NORMALLY STRAIGHT FORWARD IN REPAIRS.

I have also ridden my bike in several rain showers and never had an issue so thats why I was surprised that I had moisture in there at all.

After reading alot of these post, it appears that if we can come up with a better sealing procedure for the coils when we get them, it will save alot of problems for people down the road. I am all for preventive measures before and during installs and repairs that eliminates forseeable problems with these motors, most simple issues are preventable except for a part failure. Like the old saying "pay me now or pay me later, which is normally more expensive and causes unneccassary down time from riding our bikes.

I just wish I didn't have to pay an arm and a leg for shipping from the west coast to get my parts in under a week and a half, thats what bites the most when I have issues, I (we) can't just run out to a parts store and grab some items off the shelf and have it back running that day. I am seriously thinking of starting an online parts service here on the east coast, maybe one of the online vendors will see the benefit and marry up with me and get it up and running. I know us guys over here would apprciate getting our parts quicker with out having to pay thru the nose for it.

Thanks again, I will keep an eye out for suggetions

Ron