Hunt magneto and dead spark plugs

[reverb]

...hello, so yesterday was a hot weather day and I was riding my 48 Triumph for a long distance, then I decided to stop by the side of the road then no more sparks at the plugs...
Was a "bang" sound too. Then after a while the motor started and took me home.
Champion with only a few hundreds of kms. I never had too much problems with the magneto and the plugs but in short time (around 1500kms) I have been changing plugs because they become dead.

I sanded a bit the points but letting the same plugs I do not have spark. With new ones I have spark.
Never missfired.

How do I check the magneto to see a possible problem?
Could be the condenser?
The points look ok.

Thanks

[rigidpanman]

I would say the condenser or coil,it appears to be hot start problem.when it cools of it starts

Sent from my R1 HD using Tapatalk

[rhysmort]

Happened to my mag, I changed condenser and points and it's like brand new. I had to get bump started. Condenser and hot start is the issue.

Try a new condenser and see how it goes!

[shovithead]

watch the fire on the points when spinning the mag, it should give you a bluish spark, if is appears more yellow, then it is usually the condenser. If you have not done a tune up on the mag in some time, now would be the time to do one. If you get blue at the points, hook the wires and install the plugs and rotate the mag, and see if you get the same bluish spark. Gap on the plugs are important too. I have seen plug wires(which should be solid metal core, not the carbon filament style) burn up plugs too, and don't forget, most ignition problems, turn out to be in the fuel system. So inspect them for black soot. If they are tanish, you should be good. If they are black sooted up, check the fuel system.

[reverb]

...hello Rigidpan, however, today (a day after) I did not have spark as mentioned.

Hi Rhysmort, is an international order for me, hence I am asking before do anything.

Hi Shovithead, I have good color on the plugs and new carburetor. I will check if I have that spark on the points; with these new plugs I have spark and that Blueish color but with the others I do not have any spark and that is my concern; that every 1000 or a bit more kms I need new plugs.

[shovithead]

If you have blue spark at the plugs, then you have to have similar results on the mag points. The resistance on the plug wires may be eating the plugs. You did not say if the color of the plugs were good(tan) or bad (white or black). If you constantly keep the ceramic on a spark plug wet with unburnt fuel, it will foul the plug. You need to get spare plugs, go for a ride, and when it wont start, see what you have at the mag points, if anything, and or at the plugs. If you loose spark altogether, then it is probably the coil, or if you have weak yellow fire on points, the condenser. But it all needs to be checked, when it fails and is still running temps. Coils can be checked for ohms, and the wrong ohms coil can do damage to the points, or even if it is starting to break down.

[whittiger650]

shovithead has posted excellent info and his advice should be followed to the fullest. To add to that, when I have experienced what you have reverb, it was the coil gone bad. Replaced and good to go.

[rhysmort]

Originally Posted by reverb

...hello Rigidpan, however, today (a day after) I did not have spark as mentioned.

Hi Rhysmort, is an international order for me, hence I am asking before do anything.

Hi Shovithead, I have good color on the plugs and new carburetor. I will check if I have that spark on the points; with these new plugs I have spark and that Blueish color but with the others I do not have any spark and that is my concern; that every 1000 or a bit more kms I need new plugs.

Same for me dude. I'm british, took a month for the parts to come as well.

I'm saying I had the same on my panhead, I was at a weekend bike show and had to be bump started 30+ times due to no hot start = condenser.

[Tony the torch]

Everyone that owns a Hunt mag should always have an extra set of points and several condensers.

[reverb]

...the plug color as mentioned is good (tan) in the new ones still do not have a color due to the bike is in the garage until tomorrow that I will come back home (another 250kms)

Tony, I have this magneto since 18 years ago without any problem.

So today I checked for sparks in the plugs but non; I had intermittent spark on the points; slight sanded the points again and cleaned to see what happens; the spark there still is blueish. Then put the plugs but did not have a spark...then kicked several times the engine and finally fired up, then pulled off the plugs and had sparks; blueish...

Could be the kill switch with too much oil? I use an small switch hidden behind the cyl head under the air filter.

[magnum45pete]

I have been using FM magnetos for 35-40 years now and to me it sounds more like a Carburation problem,...
when the plugs soot up they stop working and you did say it has a new Carburettor on your bike........
being too rich will foul a plug real quick & easy,....
it's the nature of a Fairbanks Morse Type of magneto (FM, Hunt, Morris) that they, 9 out of ten times, either work or don't with very little come & go problems in between.
most Magneto problems come from those unlike you, who have never had them before and don't know how to set the gaps or the timing,...
one fella even broke his points by adjusting them by bending them of all things.... from what I gather you are an old hand at setting mags so if I were you I'd go look at the New Carb...... very often carburettor problems can look like Magneto/ignition problems.

[Tony the torch]

if you've had a Hunt for 18 years then it's probably one of the good old ones,
the newer ones eat condensers.

IMO. I believe it's because of incorrect indexing of the rotor.

yes, and a fouled plug can ruin a magneto, and I've seen it where a plug wire falls off, and it burns up the coil in a Hunt mag.

like Mag-pete says, carb problems get blamed on mags.... and mag problems get blamed on carbs.

[rhysmort]

Originally Posted by magnum45pete

I have been using FM magnetos for 35-40 years now and to me it sounds more like a Carburation problem,...
when the plugs soot up they stop working and you did say it has a new Carburettor on your bike........
being too rich will foul a plug real quick & easy,....
it's the nature of a Fairbanks Morse Type of magneto (FM, Hunt, Morris) that they, 9 out of ten times, either work or don't with very little come & go problems in between.
most Magneto problems come from those unlike you, who have never had them before and don't know how to set the gaps or the timing,...
one fella even broke his points by adjusting them by bending them of all things.... from what I gather you are an old hand at setting mags so if I were you I'd go look at the New Carb...... very often carburettor problems can look like Magneto/ignition problems.

Yeah this was me, mixture of a dodgy condenser and my carb! now I have both dialed in it kicks first time hot or cold!

[magnum45pete]

I wasn't thinking of you Rhys, but now you mention it, you did have some problems that in the end were carb related not magneto.
but if i'm right,.. you thought it was the mag and inadvertently created a mag problem that was infact the carb fault.....

And REVERB,....... if either cleaned or new plugs work i'd look at what is effecting the Plugs, .. and that Logically can only be the carburation.....that is re-enforced by you recently having fitted a new carb .........

[rhysmort]

Originally Posted by magnum45pete

I wasn't thinking of you Rhys, but now you mention it, you did have some problems that in the end were carb related not magneto.
but if i'm right,.. you thought it was the mag and inadvertently created a mag problem that was infact the carb fault.....

And REVERB,....... if either cleaned or new plugs work i'd look at what is effecting the Plugs, .. and that Logically can only be the carburation.....that is re-enforced by you recently having fitted a new carb .........

Little bit of both Pete, Carb was the MAJOR problem, first time with a linkert. But my condenser was also frazzled, wouldn't start warm at all. The old Fairbanks morse mags are the ones, they're bomb proof.

I agree with what you said Pete, most likely a carb issue.

[reverb]

...fellas I am not a stubborn guy but I do not get it why the carb if sometimes as mentioned, kick the engine and do not have spark and sometimes have it.

If I tickler the AMAL so have enough fuel in the bowl but no spark at plugs the engine will not fire up...
I do not have any bang on the exhaust, but if a Triumph does not fire up in 1 or 2 kicks something is happening.
Also, may be another problem could be the valves?

The other plugs had a tan good color; I am not lean or rich with the carb.
Do not forget too, that with the hot weather and these very old machines is better to be in the rich side than on the lean side.

[Tony the torch]

Originally Posted by reverb

Could be the kill switch with too much oil? I use an small switch hidden behind the cyl head under the air filter.

disconnect the wire at the mag, if it runs it's likely in the switch.

[JAWS]

^^ this first. Eliminate that variable. Then on to another. One thing at a time. Plug wires? Condenser? Coil resistance..

You have recieved great advice so far and you are a smart guy. Wont take to long and you will be up in the wind.


Dont forget intake leaks.

[reverb]

...will do. Seems that sometimes I do not see the evident...Thanks

Jaws, fortunately this bike is a great partner and no matter that poor spark, took me to my parents home and tomorrow will take me to my home. Is a long trip with again hot weather but I am confident.

[JAWS]

Thats great!! They will eventually sort out. symptoms aren't the real problem as you know, just indicators to help find it.