Topica Loopframe_Guzzi Archive


Subject: RE: ? ignition wiring?

Author: Greg Bender

Date: Aug 22, 2005, 4:56 AM

Post ID: 1719330958



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
http://www.thisoldtractor.com/gtbender

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

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

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