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Coil protection

Started by Fj1200buggy, September 09, 2013, 11:28:51 AM

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Fj1200buggy

Hi, I just got my new cdi and coils after burning a coil and cdi....I was wondering if I can put a fuse between each coil and the cdi to prevent this from happening again, is it possible?
Thanks.

FJ111200

There should be a fuse for the ignition in the fusebox.

How did the bike manage to burn a coil and the CDI in the first place?

Fj1200buggy

I wish I knew, it started cutting out randomly and started after cooling off, but then it just died and lost spark.

Pat Conlon

Do the coil relay mod, a fuse will protect that dedicated circuit along with giving your coils more voltage.

Protect your ignition box thru your wiring harness via the oem fuse.
1) Free Owners Manual download: https://tinyurl.com/fmsz7hk9
2) Don't store your FJ with E10 fuel https://tinyurl.com/3cjrfct5
3) Replace your old stock rubber brake lines.
4) Important items for the '84-87 FJ's:
Safety wire: https://tinyurl.com/99zp8ufh
Fuel line: https://tinyurl.com/bdff9bf3

Fj1200buggy

Quote from: Pat Conlon on September 09, 2013, 11:59:23 AM
Do the coil relay mod, a fuse will protect that dedicated circuit along with giving your coils more voltage.

Protect your ignition box thru your wiring harness via the oem fuse.

Can you elaborate please?

RichBaker

Rich Baker - NRA Life, AZCDL, Trail Riders of S. AZ. , AMA Life, BRC, HEAT Dirt Riders, SAMA....
Tennessee Squire
90 FJ1200, 03 WR450F ;8^P

Fj1200buggy

Thanks, I started it up yesterday with 5 amp fuses at the coils, it ran well but when I revved it the fuses blew and the bain fuse also blew. I put in new fuses but now it wont start. The coils as well as the cdi gets a bit warm.
Please help.

Fj1200buggy


movenon

Quote from: Fj1200buggy on September 15, 2013, 09:38:28 AM
How do I test the coils?

Ohm meter. Primary side 2.7 ohms + - 10%
               Secondary  12K         + - 20%

               Pick up coil resistance 120 ohms

               6-30 1984 Yamaha Service Manual

If that helps  :dash2:

George
Life isn't about having the best, but about making the best of what you have...

1990 FJ 1200

Fj1200buggy

Thanks George.
I am sick of this now, my "new" coils have 3 ohm primary but no reading for the secondary! What is causing this?

Fj1200buggy

Ok, I measured incorrectly, the secondary side is just over 12k, how do I test the pickup?
sorry im still new to this.

fj1289

Fj1200buggy - how lohttp://www.y9racing.com/Tech/Documents/Wiring%20diagram.jpgg have you had this buggy?  What are you using for a wiring harness?  Is it a cut down stock motorcycle harness?  Or a wiring harness made formthe car? 

Really sounds like the problem is in the harness, and that is causing your ignition problems and burning up cdi and coils. 

If the buggy is new to you and you do not know much about the wiring, I would consider replacing it all (or at least the engine portion).  I would use a legends car wiring diagram to make a new harness.  Sounds like that would be a lot easier than replacing cdi and coils often. 

Here is an example:  http://www.y9racing.com/Tech/Documents/Wiring%20diagram.jpg

movenon

Quote from: Fj1200buggy on September 16, 2013, 06:29:03 AM
Ok, I measured incorrectly, the secondary side is just over 12k, how do I test the pickup?
sorry im still new to this.

Pick up is located down on the left side of the engine, in line with the crank under the plate labled (YAMAHA), 4 screws to removed the plate. Should be an orange-black and grey-black wires. On the pick up there is probably 3 wires, the solid black one would probably be ground. I think it feeds up to your CDI box (the smaller of the 2 connectors).

Please keep in mind I am using an 1984 wiring diagram here. But not much changed until 1991 and most of that I think is because of the ABS system, In 1988 or there about it looks like they change the location of a few items but they do the same job?? No expert here....

Sounds from your description that you have a short to ground somewhere.... Wish I knew more about the electronics inside the CDI box. I guess someday I should get the scope off the shelf and start probing to see what normal is...

If you as you say your coils are getting warm I would also check the plug wires and caps for a short to ground just because.

I know just about enough about the electronics and electrics of the FJ just to get me in deep shit... Needless to say check EVERY connector closely. Not just the spades but also where the wire inputs to the connectors and the wires themselves. Especially up front in the head area , lots of possable "pinch" points and flexing / breaking. Lots of things to check. Make sure your kill switch isn't shorted out or even more embarrassing "on". But it happens.  :lol:

George
Life isn't about having the best, but about making the best of what you have...

1990 FJ 1200

FJmonkey

Quote from: movenon on September 16, 2013, 11:21:09 AM
I guess someday I should get the scope off the shelf and start probing to see what normal is...

George, you should know better by now... :ireful: You can't use the words "Probing" and "Normal" in the same sentence with this group.  :shok: :shok: :shok:
The glass is not half full, it was engineered with a 2X safety factor.

'86 Ambulance - Bent frame, cracked case, due for an overhaul
'89 Stormy Blue - Suits my Dark Side

movenon

Quote from: FJmonkey on September 16, 2013, 12:32:25 PM
Quote from: movenon on September 16, 2013, 11:21:09 AM
I guess someday I should get the scope off the shelf and start probing to see what normal is...

George, you should know better by now... :ireful: You can't use the words "Probing" and "Normal" in the same sentence with this group.  :shok: :shok: :shok:

Ok, OK....  :dash2: My bad....  :lol:
George
Life isn't about having the best, but about making the best of what you have...

1990 FJ 1200