Topica Loopframe_Guzzi Archive
 

Subject: RE: ? ignition wiring?

Author: ju-@astrocomma.com

Date: Aug 22, 2005, 7:39 AM

Post ID: 1719331521


John may have a non-resistor coil. Which means it may not be
bad, but not the correct type for his bike.

I don't know why or what the difference is or if a non-resistor
coil will cause damage.

--- Greg Bender <gr-@thisoldtractor.com> wrote:

 Hi John,

Yes, I think it is time for a new coil (unless anyone with
more
electical/coil experience corrects me). I just went out and
checked mine
and it was reading 4.4 Ohms across the terminals. This is the
old one
that I used before I installed electronic ignition. I've got a
bunch of
cross-references on my website that should help you find one
local and
cheap. Or, just get one from MG Cycle (http://www.mgcycle.com)
-
although I couldn't find one on their website???
http://www.thisoldtractor.com/gtbender/loopframe_electrical.htm#coil_alternatives
 


John Fish wrote:
 

Greg Bender wrote:
 
Thanks, Greg! I took the ground wire off the coil, then I
checked
 resistance across the + and - terminals of the coil. I am
geting 1.8
 ohms. Time for a new coil, do you think?

John



 Hi John,

Here are a few things you can check...

First off, it seems that most of your wiring is correct.
However, you
 
 state that you are connecting the negative terminal on the
coil to
 
 ground. This should not be. There are two possible wires
that connect to
 
 

the coil negative terminal. One wire goes to the
tachometer (which you
 
 may or may not have) and the other wire goes to the
distributor and
 
 connects there (along with the wire from the coil).

Second, you state that the positive coil wire is coming
from the
 
 ignition switch. That is correct and you should be getting
12.x whatever
 
 

volts there with the ignition switched "on". I'm not sure
what voltage
 
 you would have if measured between the positive and
negative terminals
 
 on the coil??? But, I don't think it is a valuable
measurement to worry
 
 about. I believe the best check is for ohms across those
terminals (with
 
 

no juice flowing). You should have 3 Ohms of resistance
when measured
 
 that way.

Third, make sure that the connections from the distributor
to the spark
 
 plugs are correct. The one nearest the left side of the
bike goes to the
 
 

right (#1) cylinder. The one nearest the right side of the
bike goes to
 
 the left (#2) cylinder.

Fourth, make sure that your points are properly gapped.
This is done
 
 with the left cylinder (#2) at TDC. Just follow the
directions in
 
 Chiltons or the workshop manual...they both do a decent
job of
 
 describing the procedure (both are available for download
from my
 
 website).

Fifth, make sure that your distributor cap and rotor are
installed
 
 properly and good shape.

Finally, if you've done everything and it still won't
start, I've found
 
 that a jump start from a running car gives the extra spin
needed to get
 
 everything going. This was when I was using a garden
tractor battery
 
 instead of the massive upgrade I've got installed now! :>

Hope this helps and be sure to let us know how it goes.

Regards,

Greg Bender


John Fish wrote:
 
My new-to-me 1972 Eldo has no spark. It had an SK
enterprises CDI unit
 
 
 on it that I took off in a quest to simplify. It died
on me on my first
 
 
 


ride while the CDI unit was still on it. I would like
to review the
 
 
 wiring of the coil and distributor. Please bear with
me, as I am not
 
 
 good with electronics, so speak slowly and clearly and
don't make any
 
 
 sudden moves. :) Also, I got about 6 bee stings while
mowing the lawn
 
 
 and the benadryl is making me dopey (er).

White wire from the ignition switch to the "+" terminal
of the coil.
 
 
 wire from the "-" coil terminal to the distributor
terminal in paralell
 
 
 with the condensor. wire from the "-" coil terminal to
ground. wire
 
 
 from the center of the distributor cap to the center of
the coil. spark
 
 
 


plug wires to the plugs.

No spark at the plugs. no spark when I take off the
wire next to the
 
 
 condensor, turn on the ign, and hold it close to the
block while opening
 
 
 


the points.

12v measured at the battery. 10.8v measured across "+"
to "-" at the
 
 
 coil.

New condensor.

Sorry about the length.

John

1972 Eldo
2000 V11 sport



Regards,

Greg Bender
1971 Ambassador
2000 Quota
http://www.thisoldtractor.com/gtbender

Florida MGNOC website
http://www.thisoldtractor.com/fl_mgnoc

Minnesota MGNOC website
http://www.thisoldtractor.com/mn_mgnoc



1972 Eldo
2000 V11 sport



Regards,

Greg Bender
1971 Ambassador
2000 Quota
=== message truncated ===


Ted Ward

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