H mag update

Zachary Hoyt · Jun 22, 2010

I went to a funeral this morning and stopped by the H on my way back through the woods. I cleaned all of the connections on the condenser and wires and checked the timing. I got a spark from the coil when I put a plug in the coil wire and grounded it, also got a light shock. Still nothing at the plugs. I looked at the plug wires the previous owner put on and they say 'ultra 7mm high suppression' or something to that effect. I did some reading on here and saw reference made to non-copper core wires making the coil overheat and fail and not letting enough voltage through, so I'm thinking of changing the coil and the plug wires and seeing where I am then. I am also considering sending the mag out to be professionally rebuilt, but I'd like to do it myself if I can. It's quite a stretch to reach the starter switch while holding the spark plug against the block, one of those times when I wish there were two of me. I'm hoping to be able to get the coil at NAPA, but I'll just have to wait and see.
Zach

El Toro · Jun 22, 2010

You should be using copper plug wires with that mag. There's was a man in NY that rebuilt the IH mags. He called himself The Magman, but I haven't seen any of his postings for a long time.
He has rebuilt mag for some of the people that post on here. He may have some health issues. Hal

Jeff Z. · Jun 22, 2010

El Toro, If you don"t mind send me an email so I can reply to you with a IH problem.

Janicholson · Jun 22, 2010

The spark (and shock) are an indication of at least usable spark. The rotor must be timed correctly to the gear to make it work correctly. There are marks on the gear and drive gear to align. I also believe in low resistance wires. I like magnetic suppression wires with real wire wound around a fiber core. (MSW) wires cost some more, but keep radio interference down while working well with a mag. (or regular distributor)
If the rotor is timed correctly, the rotor or cap might be cracked, or have carbon tracking that leads the spark to ground. Good luck, Jim

Tom Fleming · Jun 22, 2010

Zach, it is relatively easy to do a basic rebuild of an H4 mag. If all you are going to do is clean it up, replace the coil, points, condensor, and re-grease it, do it yourself. If you want, you can call me and I can talk you through it in about 30 mins, while you are doing it.

Nebraska Kirk will also rebuild your mag.

Zachary Hoyt · Jun 22, 2010

Thank you very much for the advice. What do the marks look like on the two gears? I timed it roughly by bringing #1 up till the impulse clicked with both valves closed and then pointing the rotor just past the #1 contact on the cap, but I don't know that that is sufficient. I have a new cap and rotor with no more than 5 hours run time, so I'm thinking they're probably good. Would the wires I have prevent a weak spark from reaching the plugs, conceivably? Thanks again,
Zach

Zachary Hoyt · Jun 22, 2010

Thanks very much. I've already replaced the points and condenser,
so it sounds like all I really have to do now is the coil, and the
greasing. Where should I put the grease, and what type? I have
white lithium grease if that is good, or I can get some other kind.
The new condenser is shorter than the old one and has a separate
leg that screws onto it to make up the difference, but I assume it is
supposed to be like that.
Zach

gene bender · Jun 23, 2010

You font want the rotor past the tdc. Line the rotor to the tower it fires as you want fire at TDC.

H mag update

Zachary Hoyt

Well-known Member

El Toro

Well-known Member

Jeff Z.

Well-known Member

Janicholson

Well-known Member

Tom Fleming

Well-known Member

Zachary Hoyt

Well-known Member

Zachary Hoyt

Well-known Member

gene bender

Well-known Member

Similar threads