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Wampus_cat

Bad coil..?

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So, I was riding on a very hot and humid day, and the ol girl (87 fourtrax 350) suddenly stopped running.  I got it pulled home, discovered no spark. Couldn’t get an ohm reading on the secondary coil. Ordered a new one off eBay, brand new genuine Honda... hooked it up still no spark, so I took it off and brought it to the multimeter, and I’m getting out of  range reading on the primary coil but no reading on the secondary as pictured (exactly like the old coil).  Am I doing something wrong here? 

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Edited by Wampus_cat

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You’re on page 17-4 of manual?

primary resistance pole to pole 0.1 to 0.2 Ohms not KOhms

secondary (cap on) green terminal is 7.5 to 10.5 KOhms

secondary resistance (cap off) is 3.7 to 4.5 KOhms.

ignition system troubleshooting on page 17-3. 
yours is an 87 TRX350A?

is your meter set low enough — can you select a lower range setting when checking primary?

 

Edited by Goober

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I was following that section of the manual. The meter is to the lowest setting and I read .5 between the green terminal in the black terminal, but I cannot get a reading between the green terminal and the end of the wire, I am definitely contacting the wire out on the end… I even had an electricApprentice try it and he got the same result

it is a 350a

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Hi: Place your meter on the 20K setting when reading the secondary to Primary

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Yeah because the primary reading is in low range; the secondary reading is in high range (K Ohms).

 

As Shadetree mentioned the ignition diagnostic does mention failure of CDI as possibility 

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So... upon further testing I seem to have continuity (when I should have none)between bl/w and g/w for the kill switch. I never use it anyway, is it difficult to bypass?

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im not sure what you mean

the kill switch circuit is open on RUN

the circuit is closed in OFF position 

 

this is opposite from Foreman kill/run circuit 

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Hi: Have you got the kill switch unplugged when checking it?

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30 minutes ago, Wampus_cat said:

I was just going by the manual, which I didn’t see mention that.. where would it unplug

Manual is put together with the under standing one has a strong know how of electrical systems.---- so unplug it to test it.

 

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The best place would be to unplug the CDI -- Put your meter on the Ohm scale --place the red test lead on the Bl/W wire on the CDI connector and the black test lead on any green wire you find -- then switch the kill off/on to test it.

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I did that, except the kill button doesn’t switch on off, I suppose because I don’t use it... can it be bypassed easily without messing up anything?

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The kill switch doesn’t click or what?

 

the switch assembly has a detent ball in it like the safety switch on a Mossberg shotgun.

 

mine didn’t work either but i disassembled it and put the ball back in the Center seat. You can try disassembling it but do it over something that will catch the ball and spring.


See the three seats? And the ground connectors on seat 1 and 3? You only have connection in KILL position. the worst is trying to resolder the ground wire if you break it off 

 

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Edited by Goober
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I removed the switch and harness completely as a bench repair job.

 

Remove the lighting and start switch assy and cabling from the quad.

 

remove the red kill switch cover by lightly prying on it with a large flat blade screwdriver. It will easily pop off.

 

Unfasten the kill microswitch from the L&S switch assy by removing two small screws. Pay careful attention to the orientation of the microswitch and other wires.

 

use a small flat blade screwdriver to Remove the white outer microswitch cover by carefully prying two clips.

 

same thing to open the microswitch. Careful not to lose the detent ball and spring. I dropped mine in the garage and spent awhile looking for it!!! Be very careful not to break the solder joints.

 

See that little shoe that makes the kill connection when the ball is in seat 1 and 3?

 

If dirty, Clean the inner works with contact cleaner and plumbers flux brush—that detent ball and spring socket gets rust/dirt in there and causes rough switching. Inspect those three detent seats and the track for excess wear. Apply a thin film of permatex dielectric grease to the ball socket and detent track. Reinsert the spring and ball into the center seat and close up the switch. 
at this point you can flick the switch open and closed to check your work.

reinstall the microswitch and ohms check the circuit to be sure it operates properly.

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14 hours ago, Wampus_cat said:

I did that, except the kill button doesn’t switch on off, I suppose because I don’t use it... can it be bypassed easily without messing up anything?

Yes It can be disconnected 

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Ok thanks goober, I was able to fix the switch with your tutorial, but alas, still no spark.  Gonna get a new cudi box and spark plug

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22 minutes ago, Wampus_cat said:

Ok thanks goober, I was able to fix the switch with your tutorial, but alas, still no spark.  Gonna get a new cudi box and spark plug

The Bl/W wire from the switch, along with a separate white socket, goes over to the main harness right inner fender. It plugs to a single Bl/W socket. It’s next to the white plug

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