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General Category => Yamaha FJ1100 / FJ1200 Running Problems => Topic started by: jseaman on June 25, 2017, 03:26:49 AM

Title: No spark
Post by: jseaman on June 25, 2017, 03:26:49 AM
Hi all,

I inherited a project a couple of weeks ago in the form of a '93 FJ1200. It hadn't been on the road for a few years and needed a lot of work. This is the first bike stripdown I have done so a bit of a learning curve (they're very fiddly!), but I have sorted the frame, new sprockets, fork seals, filters etc.

Before I did anything I got it running but it was very slow to fire - it cranked well and the fuel pump was obviously working but it wouldn't run. Eventually it did fire up and that was good enough for me so I set to work expecting that the hand tight spark plugs and mouse nest in the air box would be contributing factors to not wanting to fire.

Now I've come to the reassembly stage and I have good cranking, fuel pump whizzing away to the point it's coming out the overflows but no spark at all. The coils are connected and the 10mm bolt underneath has a ground connection to it, I'm assuming the ignition module in the front fairing is the next port of call but thought I'd see if I could get any pointers before I blindly attack it

James
Title: Re: No spark
Post by: jseaman on June 25, 2017, 04:37:01 AM

Just a quick update - I have taken a look at the kill switch after reading a few posts and it looks good

(http://img.photobucket.com/albums/v312/JSeaman/242.jpg) (http://smg.photobucket.com/user/JSeaman/media/242.jpg.html)

I've got 12V to both sets of coil wiring

(http://img.photobucket.com/albums/v312/JSeaman/244_1.jpg) (http://smg.photobucket.com/user/JSeaman/media/244_1.jpg.html)

The pick up looks reasonable (although needs electrical testing)

(http://img.photobucket.com/albums/v312/JSeaman/245_1.jpg) (http://smg.photobucket.com/user/JSeaman/media/245_1.jpg.html)



Before, during and after pics just for fun:

(http://img.photobucket.com/albums/v312/JSeaman/2_2.jpg) (http://smg.photobucket.com/user/JSeaman/media/2_2.jpg.html)
(http://img.photobucket.com/albums/v312/JSeaman/121.jpg) (http://smg.photobucket.com/user/JSeaman/media/121.jpg.html)
(http://img.photobucket.com/albums/v312/JSeaman/241.jpg) (http://smg.photobucket.com/user/JSeaman/media/241.jpg.html)
Title: Re: No spark
Post by: jseaman on June 25, 2017, 08:34:31 AM
The plot thickens, I've got a couple of Ohms over the primary coil and open circuit over the secondary

So my question is now - what would cause both ignition coils to pop at the same time?!
Title: Re: No spark
Post by: Pat Conlon on June 25, 2017, 11:10:33 AM
Quote from: jseaman on June 25, 2017, 04:37:01 AM
The pick up looks reasonable (although needs electrical testing)
(http://img.photobucket.com/albums/v312/JSeaman/245_1.jpg) (http://smg.photobucket.com/user/JSeaman/media/245_1.jpg.html)

^^^ What did the test on the pick up coil show? That will affect both coils. Check and clean all the connections to the DCI igniter box?

The run/off handlebar switch may be in good shape but what about the wires running to and from the switch? Fuse box to switch. Switch to DCI box. That circuit powers the DCI box and if you have a loose or bad plug connection or bad wire in that circuit = no spark.
You can always run a test jumper from the battery + to the DCI igniter to assure that the box is getting full 12v power.
Read your wiring diagram to see which wire is the 12v input to the DCI box. Don't cut the wire, just (carefully) skin the insulation back and use a alligator clip.

Electrical gremlins are fun especially when you factor in rodents.
Title: Re: No spark
Post by: jseaman on June 25, 2017, 04:42:02 PM
Hiya,

Thanks for the feedback I went to measure the pick up and found it kind of wasn't plugged in :) Well, to be precise it was plugged into the wrong connector (which it will happily fit in), so the question becomes what should this be connected to - just next to the fuel pump wiring:

(http://img.photobucket.com/albums/v312/JSeaman/IMG_7883.jpg) (http://smg.photobucket.com/user/JSeaman/media/IMG_7883.jpg.html)

It fired on the first turn when it had a crank signal!! Although it doesn't explain why the coils are o/c

And yes, rodents add to the challenge :)

Title: Re: No spark
Post by: FJ_Hooligan on June 25, 2017, 05:24:56 PM
Quote from: jseaman on June 25, 2017, 03:26:49 AM
I inherited a project a couple of weeks ago in the form of a '93 FJ1200. <snip>

Now I've come to the reassembly stage and I have good cranking, fuel pump whizzing away to the point it's coming out the overflows
but no spark at all.

Not sure what's causing the loss of spark, but if the fuel pump is forcing fuel out of the overflow then you've got additional carb related problems.

Been a while since I ohmed coils but shouldn't the secondary ohm as open since it "shorts" to ground across the spark plug gap?

Also, I remember getting funny readings on the primary side if the power wires are hooked up.

DavidR.

Title: Re: No spark
Post by: jseaman on June 26, 2017, 05:56:31 AM

The fuel was being forced out because the pump was forcing fuel in every time it primed

The primary wires were disconnected when testing (they need to be really, that measured through fine

I believe the secondary is supposed to be ~15-20KOhm but can't get anything on it

My remaining question is about the plug, what should it go to?!

Title: Re: No spark
Post by: Pat Conlon on June 26, 2017, 11:03:31 AM
Quote from: jseaman on June 26, 2017, 05:56:31 AM

The fuel was being forced out because the pump was forcing fuel in every time it primed


^^ Wrong answer
Title: Re: No spark
Post by: jseaman on June 26, 2017, 11:50:34 AM
Quote from: Pat Conlon on June 26, 2017, 11:03:31 AM
Quote from: jseaman on June 26, 2017, 05:56:31 AM

The fuel was being forced out because the pump was forcing fuel in every time it primed


^^ Wrong answer

Very helpful?!
Title: Re: No spark
Post by: Pat Conlon on June 26, 2017, 12:16:40 PM
Anytime fuel is forced out of the carbs is an abnormal condition. Something is wrong. Most common cause is debris in your float needle seats preventing them from closing along with a possible stuck float. Also common are the O rings on your float needle seats become dry and hard and thus start leaking.
As Hooligan states above, you have carb issues. Time to clean your carbs.
Buy this kit: http://rpmracingca.com/proddetail.asp?prod=carbkit&cat=24 (http://rpmracingca.com/proddetail.asp?prod=carbkit&cat=24)
It has all the o rings you need to have at time of carb cleaning. It also has ss allen screws that will replace all those frozen soft JIS screws you will knacker when you try and loosen them.

There is an unused plug on the right side of the harness. This plug is used for the vapor recovery system on certain USA models.
Title: Re: No spark
Post by: jseaman on June 26, 2017, 01:24:59 PM
Now that's helpful, thank you
Title: Re: No spark
Post by: balky1 on June 26, 2017, 01:26:15 PM
Quote from: Pat Conlon on June 26, 2017, 12:16:40 PM
Anytime fuel is forced out of the carbs is an abnormal condition. Something is wrong. Most common cause is debris in your float needle seats preventing them from closing along with a possible stuck float. Also common are the O rings on your float needle seats become dry and hard and thus and start leaking.
As Hooligan states above, you have carb issues. Time to clean your carbs.
Buy this kit: http://rpmracingca.com/proddetail.asp?prod=carbkit&cat=24 (http://rpmracingca.com/proddetail.asp?prod=carbkit&cat=24)
It has all the o rings you need to have at time of carb cleaning. It also has ss allen screws that will replace all those frozen soft JIS screws you will knacker when you try and loosen them.

There is an unused plug on the right side of the harness. This plug is used for the vapor recovery system on certain USA models.

I see you guys have a lot of problems with carb screws. Although they are soft, I think we in Europe have a bit different screwdrivers? At least I've got ones that fit in the heads perfectly.

PS. For some reason I thought jseaman is from Europe, but I must have mistaken him with someone else. Sorry.
AHHH! Now I see! British licence plate. I don't know what type of screwdrivers they have (like they are not in Europe  :wacko2: ).  :dance2:
Title: Re: No spark
Post by: jseaman on June 26, 2017, 02:49:23 PM
We're still in Europe :)

Yes England

The connector was for the rear brake, just found it