No spark. No fuel pump. (Cross posted on FB)

Hey all. New to VFRs. Saved this beauty from a customer on my mail route this summer for 800. It's an 87. It has ran fine for 3 tanks worth of fuel. Did the basics. Oil change etc. tanks a bit rusty but it can wait till fall. It has sat for around 6 years. The last two of which have been outside. Ran seafoam through it on the first tank and adjusted the idle screw and she purs like a fat cat but it's good till the carbs come out this fall.

She's not running ATM and I can't figure out why. The past 4 or 5 rides I noticed the pump not priming and I had to hold the starter longer and longer for it to start up. That last run she had it took about 20 seconds. I bypassed the pump and it would do the same thing. Also took the pump out and 12vd it and it runs fine so put it back in. Noticed it was sitting directly on the metal clamp so I wrapped it in thick electrical tape until I can find another rubber or foam sleeve for it. Figured it was just shorting itself out but that didn't fix the issue.

Started taking her apart last night to check different things and ended up finding I had no spark. Plugs were blackish so hit them with carb cleaner and sandpapered the ends and still not spark. Which has me nervous.

Other things I checked
*Clutch sensor and bypassed
*Took apart and cleaned Killswitch also bypassed
*Could not find a kickstand sensor
*Checked all fuses
*Had battery on battery charger that has a health sensor in it. Batt is fine
*Starter fluid (before finding no spark)
*Contemplating setting it on fire

I bought the bike as a running project and it was getting torn down as close to the frame as I'm comfortable for cleaning and repaint. So I knew I'd run into something. I'm a mechanical guy not electrical so I don't know where to go from here. The Bible doesn't show up till Wednesday so I'm restricted to here and forums. I don't have a whole lot of electrical knowledge with bikes as this is my second bike and my first is newer and runs fine. People on the forums mention checking coils, pg, cdi, rectifier ext in other posts but I only know what the coils are and I'm not sure how to check any of them. I'm also curious about the neutral safety switch on it but don't know anything about it.

And the icing on the cake is I walked out this morning and tried it while it was torn down and it fired right up ran for less than 2 seconds and died. And then continued to show all of the above symptoms. It did this twice yesterday as well but not immediately after trying a fix.

Any help is appreciated. Sorry for the info dump. Thanks all. And so far I love having it lol. Next bike I get will probably be a Honda just because it sat for 6 years. We put gas in it. It started up and I rode it home in the condition it was in lol amazing reliability. (I used to work at the Marysville auto plant and my dad worked at the motorcycle plant)

UPDATE: After putting the spare pulse generator in and it reading the same Resistance and not fixing the problem. I put in the spare spark box that I bought at the same time as the pulse generator since I figured it'd be a good idea to have one on hand since you can't really test for them. The spark box had gone bad. Bike runs perfectly now. Still need to clean the carbs though.

 

Okay so I found a buried comment on the forums about a guy that has a 88 model ( different I know but some things are similar) and it turns out the fuel cut relay will refuse to let the fuel pump run if there is no spark. Unsure if that includes priming but it's something.

Looks on a wiring diagram like coil pack 3 runs to the fuel cut relay which is the only thing that determines wether the relay triggers. So my next step is to test that coil... I think lol

( Sorry using this as my notepad to keep things straight.)

 

never use sandpaper on plugs, wire brush only. checking coils is ez, measure primary resistance first. measure charging voltage @ 5000 rpm asap. inspect wiring around r/r for melting or burning, also wires on starter solenoid connections.

its ez to bypass fuel pump relay so its powered whenever key is on. manual will show how.

(***FB SUKS***)

 

Well my impatience got the better of me and I went out into the garage and set up the shop lights. I took all fairings off and inspected every connection/connector I would find, unplugged, inspected, and cleaned them and reconnected. I did find that had melted at some point and someone bypassed one of the three wires (the three yellow ones running into the trans, I assume this is from the stator to the rectifier?) so I snipped the connector and crimped and shrink tubed all three until I can get another plug. Other than that everything looks fine. I found two grounds (one at the batt and one at the right lower coil) and got them cleaned up. I will have to break out the wiring diagram and start looking at continuity on different things tomorrow and checking coils. After everything I just did I tried firing her up and she popped one time then nothing.

Also I could not find anything in the 86 manual specifically on the fuel pump ( ik different year but the 87 will be here next week) could you elaborate more on wiring the pump into the ignition.

 

Just for Info.
Your ICM (Ignition Control Module) Must see either the Ground from the Neutral Switch (for a Neutral Start) OR the Ground from the Sidestand Switch (while riding or In Gear Clutch pulled in Start). If BOTH Grounds are missing at the ICM you will have No Spark.
Referring to my RC36 drawing.

 

87 doesn't have a side stand safety. But switching into gear without the clutch pulled in will not fire the starter motor so I assume both the neutral safety and clutch safety are working fine.

 

So as I go to bed, I found a wiring diagram online. Devices that have been tested are crossed out. Grounds that have been cleaned have been crossed out. Connections that have been inspected cleaned or repaired have been crossed out.

 

Yep ok sorry I was looking at the wrong diagram for your bike.
Checking your diagram there is no spark unit interlock, the Neutral and Clutch Switch work as saftey interlocks for the Starter Relay only.

Have you confirmed with Ignition to On, Kill Switch to RUN that you measure 12v at the Black/white wire at the Spark Unit?
Does the Green ground wire at the Spark Unit have continuity back to the battery Negative?
Check the main Frame Earth point is clean and tight, well bonded to frame and good continuity to the battery Negative terminal.

 

I went out this morning and cleaned up a few more connections, and found some more grounds. I checked the Stator as well by just checking each of the yellow wires for a short to ground and there was none. also found out my clutch switch is in fact bad, so i brought it in to rebuild, just needed some sanding on the terminals and the connector. after half an hour of trying to put it back together the spring shot across my office so there's $10 lmao. BUT the clutch switch has been bypassed this whole time so that's not the issue.

There is continuity between grounds and neg, I checked the ohms on all the coils and they all came back between 3.1 and 3.3.
There is 12 on the b/w to the cdi and continuity on the green to neg.

I have updated the diagram to match what i have now done. mind you the two above wires are the only ones i have checked for continuity at this point. but the harness in general looks in good shape.

The switch rather pissed me off so I am taking a break till this afternoon lol

 

Jumped the gun and went ahead and pulled the cdi and inspected it and I'm struggling to find anything out of whack. If anything the thing looks next to new. I can't find broken solders. Browned resistors, or swollen capacitors
So I suppose I can scratch that off the list as well.

That leaves the R/R , Pulse Generator, and the Stator (assuming I tested it wrong, but the plug for it was melted), and bad wiring in the harness correct?

 

thats so scarey from one black box to......

now i have to worry that any one of those 10,000 things could crap out at any time while im riding, great.

 

Really-? I have definitely done that in the past with no ill effects that I know of. What's the prob. w/ sandpaper?

 

I have definitely folded over some sandpaper and ran it thru the gap, re-checked the gap and cleaned with contact cleaner. Never had a problem.

 

That's what I've done also.

 

you're a f*in genius, man

 

Does this sarcastic comment mean you have nothing to back up your claim?

 

So in an effort to keep the pissing contest on track lol, I got my manual in the mail today and immediately flipped to the pulse generator section because I don't really know anything about it. I tested it and the spec reads 450 to 550 ohms but what I'm getting is 324 ohms. The manual states that if it's out of spec needs replaced, but given that this is only one of a few things that I haven't checked, is there a good chance that this is my problem? I don't know much about the pulse generator. If somebody could kindly explain to me what job it has in the system.

 

Pulse generators often fail (and test bad) when they are hot, but not always.

ALSO... I have seen perfectly working units, hot and cold, test bad. And "bad" units, test good. The resistance test is often right, but not definitive in my opinion.

I typically exhaust my other options and then swap with another unit. But when I know my carbs are perfect and something acts up when it gets hot... it's a decent sign. ECUs can act similar, but don't seem as connected to heat in my experiences.

I do have the luxury of an inordinate amount of known good spares for testing tho too for many of my bikes.

 

The last couple of rides I took in addition to the aforementioned difficulty to start, once it was up to op temp the bike would get... "Jumpy" on harder pulls. Would this go along with what you are talking about failing when hot?

 

Yes. Not a smoking gun, but if it pulled smoother earlier in the ride before getting hot, sounds possible. Especially with resistance readings out of spec.