Hey guys, I recently took off the top of the transmission so I could swap my reverse and brake bands (brake band was chattering ... was my dad's idea). Well, i've got the car all together now, except now it won't run on magneto - only battery. I did take off the magneto post (i've got an external oil line that feeds into the magneto post - also my dad's idea), and I thought I assembled it correctly but I'm not sure. does someone have a diagram of how it ought to be assembled? I figure this is the likely source of my problem - it's the only part of the electrical system involved in the repair. Might as well start troubleshooting there, ya know? Car is a (real) '15 roadster, if that makes a difference.
John,
Make sure your battery and magneto connections to the coil box are correct. If you mistakenly connect battery to the magneto contact, you will weaken the magnets strength greatly. Should you have done that, there is a way to re-charge the magnets in the car.
If you connect an Ohmmeter to the magneto post and check the resistance to ground, it should be very low. I believe less than one Ohm. The post is actually connected to ground through the 16 coils in the magneto. If it is open, check your new oiler and also make sure there is no lint on the coil contact inside the cover.
Tom, thanks for the tip. I couldn't have connected battery to mag, as the wire at the top of the mag post was the only one i undid.
Here are some pics:
Err, there was supposed to be text with those. THe first pic is how i had it on the car.
the second is a recreation of how i had it assembled. As you can see, there is nothing holding the spring-loaded pin onto the top of the magneto, so that's why i wasn't getting any spark on mag. here's the problem - how is it supposed to hold on? what was insulating it before from shorting out thru the oil line? the pin carrier is a snug fit in the steel piece, so there doesn't seem to be any way to insulate.
Crap! The second one is supposed to be with this caption:
I took it off again, here's the different pieces. on the far right is the oil feed thingy, that screws into the magneto post on its immediate left - see the hole in the side? That steel piece screws into another piece attached to the hogshead with three screws and separated w/ a black gasket. beside that is a spring-loaded pin + carrier - that slides into the steel thing. the two nuts thread on to the pin carrier, and i had it set up with the wire to the coil box in between those.
The caption I sent in the post above goes with this pic:
Ugh, i totally effed this up -__- just ignore everything
OK here's the post i wanted to make:
I took it off again, here's the different pieces. on the far right is the oil feed thingy, that screws into the magneto post on its immediate left - see the hole in the side? That steel piece screws into another piece attached to the hogshead with three screws and separated w/ a black gasket. beside that is a spring-loaded pin + carrier - that slides into the steel thing. the two nuts thread on to the pin carrier, and i had it set up with the wire to the coil box in between those.
Loose the mag. post oiler - there was another thread with the same trouble.
steve, did you mean "lose the mag post oiler"? as in, swap it for a normal one? Because I'm considering doing just that.
looking at your pictures, it looks like you have quite a bit of threaded material sticking out the top. If you make a sleeve to go above the wider unthreaded part of that piece, it will move the tip closer to the button at the top of the magneto coils. That is one of the problems with the magneto oiler plug. It is sometimes too short to make a good connection. There should only be enough threads to put on the two nuts with the wire connection between. Don't get rid of the oiler. It can save your engine if the inside oil line gets plugged.
Norm
norm, that's good advice - but what would i do about preventing the fuel line from shorting out the mag?
Aren't there supposed to be two red fiber washers to insulate the post from the base to prevent the ground of the post to the base? I see no washers. If it was working before, but isn't now, you most likely misplaced the washers and forgot to put them in. Jim Patrick
i was wondering about that, jim - but i don't know where the washers would go. The needle carrier is a snug fit in the steel piece, so even if you put washers to insulate at the top and bottom you'd still be shorting out thru the side. The post is insulated from the hogshead by a fiber washer, but it's going to short out via the oil line which goes right into the crank-case.
The post must be insulated from the magneto base or it will ground out. I believe there is a fiber washer that goes over the threaded post before pushing it up through the base and another that goes over the threaded post on the outside and the bottom nut is tightened against it and holds the post centered inside the hole. It would make sense for there to be a small tube to insulate the post from the walls of the base, but I don't believe there ever was one of those. Perhaps you could make one using a plastic straw slit up the side and slide it onto the post and roll it around the post as you slide it into the hole and cut to the correct length. Jim Patrick
The first fiber washer is slid onto the contact and rests on it's shoulder, it keeps the larger diameter part of the contact from going up into the hole. There might/would be a fiber sleeve that goes down around the threaded part into the hole then another fiber washer is placed on top. The first nut hold the whole assembly together. Only the threaded part fits through the hole.
If the O.D of the fiber washer on the inside fits flush against the inside walls of the base and the I.D. fits tight against the threads, it would automatically hold the threaded post precisely centered in the hole. If the hole is too small, as you say, I would drill it out to a slightly larger size so that there would be no chance for the post to come in contact with the ID of the hole. Jim Patrick
He is trying to shove the whole thing up into the hole not just the threaded part as it should be.
jim, there isn't enough room to fit anything between the carrier and the steel piece. I actually haven't tried it making sure that the needle was firm against the magneto button, so i'm not 100% positive that it would actually ground out thru the oil line ... but i don't see why it wouldn't, it's a regular copper line.
mark, that's the way i remember it being when i took it apart the first time ... with the needle carrier body in the hole. And if that's not where it's supposed to go, why go to the trouble of making them such a precise fit? Thanks for the ideas everyone, keep 'em coming!
Unless the fitting for the copper line is screwed in too far it has no more chances of grounding then the body of the part that is connected directly to the hogs head. You have to have air space between the threaded part of the contact and the hole it goes through. The missing fiber washers center it in that hole.
If the post is insulated from the base properly, it won't ground out against the oil line unless the oil line fitting is screwed in so far as to touch the mag post. The mag post, from threaded tip, to sharpened tip embedded in the mag coil button, should be totally independent of the mag post housing base. Jim Patrick
John - I did mean "lose" as in replace. Replace with an original mag. post and see what happens - guarantee, it's that oiler fitting shorting out.
If it's assembled wrong it will short out as John is trying to put his together. If reading the post I think this image may be how he is trying to assemble it;
Maybe so. The way to keep the spring loaded post housing from going up into the hole is to slide the rigid fiber washer (I've seen white plastic washers used too, which are easier to find at hardware stores) over the threaded post before sliding it up into the hole from the bottom. The fiber washer will sit on the shoulder of the post and keep it from going any further while also centering the threaded portion in the hole. Jim Patrick