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Bad coil??? I hope!

You wouldn't happen to have a link or diagram of your ignition system that I can look at. Your coil has twin primary's and the plugs are series into 1 secondary winding isn't it?
 
The reason I ask is because if you do have dual primary's, you must measure each primary value independently. You may be reading the pair in series and the book is stating each one as stand alone. (1.4 + 1.4 = 2.8 which falls in the 2.5-3.0 range your looking for).
 
The reason I ask is because if you do have dual primary's, you must measure each primary value independently. You may be reading the pair in series and the book is stating each one as stand alone. (1.4 + 1.4 = 2.8 which falls in the 2.5-3.0 range your looking for).

Good point. Even at .5 - .7 ohms. From Front coil to rear coil connector would give you 1.0 to 1.4 ohms. My values came from CLYMERS FLH/FLT Twin Cam 88 1999-2003.


Manual also said to check it at operating temps. Recomended a hair drier to warm it up, if you can't get the bike started.

CLYMERS FLH/FLT Twin Cam 88 1999-2003

If he has three connectors on the primary, then he has two primary coils. Also according Clymers wiring diagram for a 2001.


I tired to find procedure for checking the coil on 2004 Harley Service Manual. It said swap with a known good one. Unless I missed it somewhere.
 
I tired to find procedure for checking the coil on 2004 Harley Service Manual. It said swap with a known good one. .

Yep. They really don't want to tell you how to bench test them out of fear you may get shocked and call 1-800-Lawyer.
 
I think that higher resitance values (2.5 to 3.0 ohms)are for pre twincam bikes.

He really needs a manual for his bike.

Couple examples:

A 1980 and Later Shovel head is 3.3ohms to 3.7 Primary and 16500 to 19500 Secondary

2007 Dyna .3ohms to .5ohms and 2750 to 3250

BIG DIFFERENCE!!!!
 
I think that higher resitance values (2.5 to 3.0 ohms)are for pre twincam bikes.

He really needs a manual for his bike.

Couple examples:
A 1980 and Later Shovel head is 3.3ohms to 3.7 Primary and 16500 to 19500 Secondary
2007 Dyna .3ohms to .5ohms and 2750 to 3250
BIG DIFFERENCE!!!!


From my book 2000 fxds Should be the same 2000/01/02

Ignition coil primary circuit test
set meter RX1
Primary coil winding resistance range= 0.5-0.7 ohms

secondary circuit test
set meter RX1K
normal resistance range is 5.5-7.5K ohms

a low resistance means short in the coil windings
high resistance means corrosion/oxidation

does this help?

signed....BUBBIE
 
From my book 2000 fxds Should be the same 2000/01/02

Ignition coil primary circuit test
set meter RX1
Primary coil winding resistance range= 0.5-0.7 ohms

secondary circuit test
set meter RX1K
normal resistance range is 5.5-7.5K ohms

a low resistance means short in the coil windings
high resistance means corrosion/oxidation

does this help?

signed....BUBBIE

Bubbie it helps same as Clymers 99-03

On the primary one wire will be front cylinder(C Blue Purple), one wire will be rear cylinder (A Yellow/Blue), third wire power(B white/black). Later models have a forth wire for knock sensor.

CLYMERS .5 to .7 ohms Primary. 5500 -7500ohms(5.5 Kohm to 7.5Kohm) Secondary.

Guy Rand I would really be interested in these measurements;

Colors and letter listed above;
Primary(three small terminals)
Power to Front Coil _______
Power to Rear Coil _________
Rear Coil to Front Coil ________

Secondary

Power(small terminal) to front _______ where the plug wire plugs in
Power(small terminal) to rear ________ Where the plug wire plugs in
Between the front and rear ________ where the plug wires plug in.

Thanks BUBBIE

Signed JONAS
 
O.k., because I have 3 pins, I understand that I have dual primary sides. If I get .9 on each side independantly, that yields 1.8 together, which is below what I have been told. Tried to call the local mechanic to see what he said, but he couldn't make the time of day. I just don't have the shop manual yet, now I wish I did. I have been trying to find it on-line, but no luck yet.

Does anybody know the tolerance on the ohm readings? The secondary readings were right in spec, but the high side is a little low, what error tolerance could be expected. Also, my ohm meter doesn't have a zero adjustment, and it ream .2 to .3 when it should have read zero. So would that make my readings that much lower?
 
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