Ok so I bought a Vertex mag for my 255......honestly I dont know much about em. Can you guys help me out on wiring and such. I just read that resister thread and was wondering if those diagrams and such are the same for magnetos. SCHOOL ME....anything, everything, it is ALL appreciated.
what b29chevy said... some general information: magnetos run off engine rpm... more you give it, hotter the spark is. you can test this by putting your finger at the end of the coil wire and spining the base, you should get a little jolt. you can run them in a street application but they are primarily used in racing.
I have a couple of questions for you! What sort of mag is it? An old Scintilla or a modern Tayor? How long as it been sitting? This will greatly affect the running and reliability of the unit. What is the advance set-up in it? If its a old Scintilla Vertex it will have a mechanical advance. This will be on the tag on the body, written something like this "1750-15" or "1750/15". This means you have 15 degrees of advance at 1750 rpm. If its locked it should have "locked" stamped on the tag. You have to run small plug gaps, between 12-15 thou. Race cars will run closer to 20 maybe more but they also get them rebuilt at the end of every season! This is important because without the small plug gap you will encounter hard starting and un-reliability because you are forceing the coils to produce a large spark to jump the plug gap. This will eventually destroy the coils. There is one wire from the connection on the side of the body. This is the ground for the mag as once it starts you can't stop it! This simply needs to wired to ground with a simple on/off switch, but not the ground for the battery, if you still have a battery of course.
Its is a Vertex mag. Its going to be going on my AV8 that I plan to drive. Not race. So if I run with small plug gaps will it be good enough for the street and be able to perform everyday without fail?....This concerns me because I plan on driving this car everyday and I dont want the mag to **** out on me. Damn you guys are getting me worried.
Scintilla mag on my banger. Its my only car is used everyday and the mag has never let me down. Changed to the mag after I had a year of misery with a NEW Mallory. Its starts easier on the mag, runs better when cold and runs better when hot. Get it rebuilt and by a proper magneto company. The tractor guys aren't really good enough. Don't even attempt to just put it on, you'll be sorry in the long run.
These mags are very durable and simple and with just a little care will serve you well.Rule #1. NEVER apply power to the post on the side or the point spring/points will be ruined almost instantly-this is the circuit from the coil primary to the points.the mag will not fire when this post is grounded, so it goes to a special ign switch which grounds this post for engine off--opens to run--the tach can hook here but must be suitable for a mag.#2 as said before plugs will have a reduced gap-I think .022 for a Vertex-or you will have a hard time starting the engine.#3 NON resistor plugs and wires only or same result as #2.Remove the cap and the locate the metal capped wire that sticks up into the cap.A spark will show here when the mag is rotated even slowly if a wire clipped to the base of the mag is held about 1/32 inch from the metal end.If you touch the end while rotating the mag you may be afflicted with temporary incontenance and certain discomfort while throwing the mag and cursing your helper. If no spark--polish the point contact surfaces with FINE (approx 600 or 800) wet or dry paper and then clean with a buisness card or other non oily paper.DO NOT file the points-they will be ruined. To position the mag for installation--find a small hole in the lowest portion of the mag body.A close fitting drill bit inserted in this hole after feeling when it slips into the slowly turned rotor, will have the mag located for firing the #1 cylinder. Some of the tractor boys are damn good on mags.And the vertex is made by scintilla--like the one mad-lad has pictured.Most sold for performance in US were set up by Joe Hunt or who was that other guy??? Good luck
Thanks Enginenut!! And thanks everyone else.......Ok here are some more questions....Sorry But as you can see. I really want to get this right, it was EXPENSIVE and cant afford to screw up.....sooooo.. what kind of wires are you guys using and where did you get them from? And... Plugs? What are you guys using for plugs? Regular Champions wont work? Once again...thanks, Daniel (mad-lad)
Don't know where your from, if your in the USA and on the west coast I would reccomend Don Zig if you need work on it, if your closer to the midwest Mag-tech in Indy, or Mitch Ford Magnetos in Evansville Indiana.
I ran a Vertex mag on the street this summer - worked ok - but I wasn't any too impressed with getting it started. But, I had dual 4 barrels with LARGE squirters so I'm sure that didn't help things. I ran NON Resistor plugs .018" gap and SOLID wires. Cranking speed is kinda critical since the mag produces a weaker spark when turned slowly. In my case the MAG was "older" meaning it sat on my shelf for a year or two before I used it - several suggested mine would start more reliably had I sent it out for a recharge, but I never did so quite possibly that was my whole issue with the so-so starting. Some days it fired instantly - other days it cranked a bit. Make sure your battery is up to snuff. I will say this once I got it running it DID run flawlessly. Initially to test mine I pulled the cap - wrapped a 16 ga. wire around the coil wire and ran the other end close to the mag body - turn slowly and watch the spark - it was BLUE so I figured it was good. No one was able to tell me a better way so I still think that's a fair test. Good Luck
You should understand the big difference between how a mag and point/coil distributor perform. The faster a mag turns, the more powerful the spark; which is the opposite of point/coil distributor. Consequently, as rpm increases, the spark from a distributor gets weaker(with a mag spark gets stronger). As another post pointed out, if the starter turns the motor too slowly, the magneto spark is weak; which explains the option of using a smaller spark plug gap. Another thing is to modify the starting procedure. Start cranking the motor, then turn on the ignition, preventing kickback, instead allow the mag to spark by disconnecting the kill circuit after the motor is turning. Further, I don't know about your particular mag, but some don't have both centrifugal advance and vacuum advance like a conventional point distributor, so street performance at low RPMs might be compromised, making it necessary to run the motor at a higher idle setting.
Piston airplane engines use dual mags for ignition. They usually have some sort of system to compensate for the weak spark during start. Small engines usually have a racheting setup on one of the mags that causes it to lag then snap forward during start. Big engines usually have the mag geared to rotate much faster than the crankshaft.
I dont think I will have to send it in. Its brand new....As for the week starts. I run a 12 volt system with a 6 volt starter and that thing whips the motor around like no ones buiness. So that should be fast enough to produce a decent spark, right?
Bttt... anyone else running a magneto on your flatheads?....Share the pros and cons and your experiance with them... Thanks Daniel.
Here's a pic of a Wico mag. It didn't like to start with a 6 volt battery either cause it was turning over to slow. Once i threw a 12 volt battery on it this thing it starts very easy. All you need is a ground to kill it. I love them!
Some have an extra box to create spark, which opperates from a second set of points, and swithches off at a pre determined speed. The lag that Max is talking about sets the spark off at TDC allowing for a better spark, I have an ole A/C mag (Not yet fitted), but there is no way to advance the spark. Outback
I ran a Vertex mag on the roadster for many years with no problems starting at all with 12 volt, the mag had not been serviced in about 25 years so the internal coils finally quit, I'm going to put new coils in it and definitley put it back in, as far as being on the road when it quits there is not much to do except you can rig an external coil to get you going or carry a stock distributor and coil for that sometimes needed road side ***istance.
Hey 4ever4....its a new Taylor/Vertex. The Advance starts at 350 Magneto RPM's. The total automatic advance is 10 Magneto Degrees. At 1100 Magneto RPM's.
Hey Mad-Lad I've run a Vertex on my flathead for a little over 32,000 miles with no problems, set plugs at 15 thousands and go for it, by the way 12 volts turning the 6 volt starter is the ticket "Doc"
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