Topic: Yamaha XJ600S Seca II - Problems

[Buber]

Check the fuel pump operation. My wife has this bike, and every time it stays longer than a week, you need to crank it a lot - it has to do with vacuum operated fuel pump.
Oh, hold on, you have choke lever on the handlebars? So you should have electric one..
Hmm, air and fuel filter to check? Iridium plugs would help too....

[bzr]

Been riding it for a while, giving it the Italian tune-up it needs. Took it to redline a few times last week.

Dumb question, however: I removed the cracked turn signals from the front of the bike, and now it won't start. What am I missing here (besides the obvious signals)? I'm crap with electrics, can I still ride it while I wait for a new set of signals to come in?

[bzr]

Well #$%*, it's been a while since I read this thread. But I got something that will almost make this worth reading...

Turns out my cheap-assed Advance Auto Parts battery was as dead as Jimmy Hoffa. So I took it down to the store and wrangled a new one for free, from the one-year warranty. Sweet. Reinstalled the busted turn signals, and now it's parked for the winter in my friend's garage. Gonna pour some stabilizer I bought from a local Yamaha shop and fill the tank and tires.

Some pictures - for my photography project I managed to borrow a car suction kit from our school, and strapped it to the tank. I took some pictures at different speeds:




^ 8 second exposure.


^ I personally love this shot.



^ This one I got an A for because I photoshopped the needles in place. In reality, I was going less than 10mph.

[edbikerii]

Glad you got that bike on the road again!  I really miss mine.

You should photoshop the neutral light out, too.

[bzr]

I was hoping I wouldn't have to resurrect this thread. The Yammy's been riding fine ever since, until today...

Going down a hill, applied the brakes, downshifted twice, let go of the clutch too soon, it ended up stalling and when I tried to restart it I got nothing. Had to put it on full choke to get any sort of idle, at which point the revs climbed to 3500RPM. Taking it off the choke, even a little bit, killed off the idle. Even after putting it in gear when I let go of the clutch the bike stalled out again.

Fortunately I was only a few feet from my house because I ended up having to push it all the way home. images/smilies/wallbash.gif

The valves were ticking noisier than usual and there was this constant, repeating booming sound as well. Checked the battery and it still read normal voltage, so it may not be the ignition system.

Any ideas?

Oh, and an hour earlier when I was starting it up to go on my ride, it took an unusually long time for the bike to run on choke before it had a constant idle. And before that it sat for about a week.

[bzr]

Quick update: just ran a compression test and got 115, 120, 115, 125. The battery still has 12 volts in it, and it sounds like only one or two cylinders are firing.

My friend suspects that I may need new plug wires, just like on the Honda...which means I'll have to drill them out of the coils (I'm planning NGK wire splices on the Honda for now). Any other possibilities as why it won't run smoothly?

[edbikerii]

Have you checked for spark?  Disconnect spark plug wires one at a time.  Put a screwdriver in each of the plug wires, and hold it 1/4" from the cylinder head (hold the insulated end so you don't get shocked).  Crank the engine (make sure the kill switch is ON), and look for an arc to gap from the screwdriver to the cylinder head.

Bad wires, coil or ignition module will have no spark or a weak spark.

Which cylinders are not firing?  When it is running, spray some WD-40, or even just plain water on the exhaust pipes right up near the exhaust valves.  See which one(s) are not boiling off the water, and you will know which ones are not firing.  A failed coil will not fire on both of the cylinders that it is connected to.  I don't remember what cylinders each coil serves on the Seca II, but you should be able to just look at it and see which coil the plug wires connect to.

When you did the compression test, how did the plugs look?  Were any of them wet with gas or oil?  Any damage?

Don't forget, you need compression (yours seems fine to me), fuel, air and spark.

[bzr]

So the bike's been sitting for a week now, and testing it out it won't even crank over. The starter just kind of whimpers itself into oblivion (and that irritating buzzing noise).

Battery reads 12 volts, high beam, signals, and horn all still work. So I fear it's a bad starter. Do motorcycle shops make house calls?

[edbikerii]

Battery is dead, try to charge it up and then get it load tested (free at most auto parts stores).

So the bike's been sitting for a week now, and testing it out it won't even crank over. The starter just kind of whimpers itself into oblivion (and that irritating buzzing noise).

Battery reads 12 volts, high beam, signals, and horn all still work. So I fear it's a bad starter. Do motorcycle shops make house calls?

[bzr]

Well, after a furious wrenching session tonight, I still have problems.

All 4 spark plugs show spark, so I'm definitely getting that to the engine. Cleaned out the airbox, realized that no fuel was getting past the petcock. So I cleaned that out too and reinstalled it, tried to jump start it from our Civic and...nothing. Battery is completely dead, and I fear that I may still not even have fuel flowing in the lines, they still felt kind of stiff.

When I had the battery load tested yesterday the guy at the battery shop recommended that I set it on a charger, which I did. Over 20 hours later (the battery tender manual recommends 15 hours) the battery was still dead. So the plan is to get the battery replaced under warranty, which may be tricky since I accidentally threw out the receipt.

After that...we'll see.

[DavePhipps]

I  would check the regulator/rectifier on the bike. From all the charging and jumpstarting your doing I  would say that it's toast, or at least getting there.
Get a multimeter and test the RR, and all relays
Some nice diagnostic instructions here
http://www.electrosport.com/technical-resources/diagnosis-center.php

BTW every time i've tried jump starting from anything I have had to replace the regulator/rectifier. The batteries are 8 amp on these bikes, if the electrical system gets hit with large amperage it seems to fry the RR. I  could be wrong, this is just  from personal experience.

[edbikerii]

It can't hurt to check the regulator/rectifier, but I have jump started my old XJ600S (electronic regulator/rectifier) and my CB550 (mechanical regulator/rectifier) several times over the years with no ill effects.  I have heard of people who have accidentally reversed the wire polarity when jumpstarting and blown electrical components, but I have never seen that happen from normal jumpstarting with booster cables done correctly.

I absolutely would AVOID jumpstarting if at all possible, however.  The best bet is to get yourself a good automotive battery charger that shuts off automatically (you'll need it for the rest of your life, anyway), set it at 2amps or less to charge, and charge up your battery fully.

In any event, the regulator/rectifier is not the cause of your running problems.

So, you know that you are getting spark, right?  You also know that you have good compression because you ran the compression test.  So what's left?

You also need fuel and air.

Check your air filter (yes, pull the tank, I'm afraid.  It really isn't that hard).  Maybe a mouse or a squirrel made a nest in there or something.

Check your fuel delivery.  Are the spark plugs wet when you pull them out after trying to start the engine unsuccessfully (with choke on, of course)?  Are all four of them wet?  Does the engine fire at all?

Could your petcock be clogged?  Could your carb jets be clogged?  You must put the petcock on the "Prime" position, since those bikes have a vacuum actuated petcock for safety reasons in the event of a tip-over.

Could the vacuum diaphragm in the petcock be cracked or leaky?  Connect a hose to it and see if it flows fuel when in Prime.  Try again while you apply vacuum to the vacuum line (a MityVac would be a great tool to own for this, too).  If you apply vacuum to the vacuum line (careful not to drink any fuel here - use a Mity-Vac if you can), does it hold the vacuum?

Could the fuel pump be defective?  Your bike has a vacuum driven fuel pump, too.  Apply vacuum to it and see what kind of flow you get.  This is a common failure mode, I understand.  I've seen that other owners have upgraded their fuel pumps to the electric fuel pumps available on later years (in Europe, at least).

So, first charge up that battery properly, and then get back into the game.  Don't give up.  I really love those bikes, and still regret the day I sold mine.

I  would check the regulator/rectifier on the bike. From all the charging and jumpstarting your doing I  would say that it's toast, or at least getting there.
Get a multimeter and test the RR, and all relays
Some nice diagnostic instructions here
http://www.electrosport.com/technical-resources/diagnosis-center.php

BTW every time i've tried jump starting from anything I have had to replace the regulator/rectifier. The batteries are 8 amp on these bikes, if the electrical system gets hit with large amperage it seems to fry the RR. I  could be wrong, this is just  from personal experience.

[bzr]

I've already pulled the tank (which was surprisingly easy, only two bolts) and cleaned out, washed, and dried off the air filter. Is it ok to use WD-40 on an air filter, or will I have to shell out the whopping $3 or so dollars for K&N Air Filter Oil?

I've also cleaned out the petcock and reinstalled it. The spark plugs are getting spark and are dry. At the time, I didn't know if the engine was firing because the battery was completely toast. I'm at school now, but the battery has been charged overnight and is now sitting on my battery tender. I've also added more fuel to the tank in case it's something as stupid as I ran out of oil.

I'll probably be making a visit home on the weekend of the 18th so I can work on the bike more and see if it runs. And I'll definitely be checking all of those things you outlined, as well as getting my fairing fixed.

[edbikerii]

If you are using a K&N, then shell out the $3 for filter oil.  The oil is what traps the dust.  WD40 won't trap anything.  Also, you're supposed to wash the filter with gasoline, I believe.  Did you follow K&N's instructions?

So, does the petcock flow fuel.  I know you've cleaned it, but did you check for fuel flow both on prime and when in Run position with vacuum applied?

For fixing fairings, go to Lowe's or Home Depot or a plumbing supply store and purchase ABS Cement (black).  This stuff is what the fairings were originally made of.  The solvent actually melts the original ABS plastic and effectively fuses it back together when you apply it sparingly.  Be very careful at first because it does dissolve the original plastic, and you don't want to apply too much.

If you are careful, you can apply the ABS cement to the rear of fairing cracks, and the repair can be as solid or more solid than the original part without needing to re-paint.

Please try this in an inconspicuous part of your fairing first so that you don't discover that your fairing is made of something else and I've given you bad advice, ok?

Once you are comfortable with this stuff, you can do all kinds of cool things with it!

I've already pulled the tank (which was surprisingly easy, only two bolts) and cleaned out, washed, and dried off the air filter. Is it ok to use WD-40 on an air filter, or will I have to shell out the whopping $3 or so dollars for K&N Air Filter Oil?

I've also cleaned out the petcock and reinstalled it. The spark plugs are getting spark and are dry. At the time, I didn't know if the engine was firing because the battery was completely toast. I'm at school now, but the battery has been charged overnight and is now sitting on my battery tender. I've also added more fuel to the tank in case it's something as stupid as I ran out of oil.

I'll probably be making a visit home on the weekend of the 18th so I can work on the bike more and see if it runs. And I'll definitely be checking all of those things you outlined, as well as getting my fairing fixed.