HeLP!

Hello. I have recently reinstalled my carbs (they are now CLeAN, clean!! I Tell you!) and am having difficulty getting the bike to start. It turns over, but the engine will not fire. I am getting spark, I have fuel, and it's a pretty brand new air filter.

Coil Specs: at coil 1 & 4: 13.72-73 at plug: 3.4
2 & 3: 14.02-03 at plug: 3.5

Just for kicks I checked for cap resistance, and all of them fall within spec: 4.83-5.02 (plus, they are brand new)

The other day I shocked myself a couple of times checking for spark against the manifold (off switch! can't... reach it..) so I know it's sparking.

I installed new dyna coils, new plugs, pulled the carbs (x3) and made sure they were spotless.

How long do you have to wait for the carb bowls to fill with fuel? Do you leave the petcock on prime?

I've looked at pics of hitachi carbs, and mine has a bunch of tubes flopping willy nilly (overflow, my guess) but on the main tube, there are 2 inlets, where on the pics I have seen, there is only one. One is between carbs 1&2, the one I am using for fuel (where the fuel filter is installed) is bewteen 2&3. NO gas leaks.

I'm getting pretty frustrated at this point. Yesterday it was running (albeit pretty poorly) before the plugs fouled yet again; I changed the plugs and then the bike would not start. Just crank and crank until the battery died.

Anyone with suggestions (that work) would be considered godlike in my eyes, and I would worship them with small animal sacrifices (lots of squirrels in the yard) and incense.

 

These bikes can exhibit an interesting phenomenon that I would not have believed if I had not experienced it first hand.

A slightly low battery can (and will) produce enough current to spin the motor over (vigorously even) but not enough to produce a nice strong fuel-igniting spark.

Pull the battery and ensure it's fully FULLY charged.

Install a set of NEW (not "these look fine") spark plugs that you have checked and gapped to spec.

Put it on PRI. See what happens.

 

Thanks bigfitz. It's a new battery, charged to 13.2 (more than 12.8, that's for sure) verified by my multimeter. I have it on a slow charge right now.

Brand new plugs. BP8ES (shop tried to sell me BPR8ES... is there a difference? They said it just has a resistor.. something I am guessing I don't need at this point.)

Plugs are gapped to .75 (give or take a few microns). I will re-assess, however.

I'm getting ready to call a mechanic. I've been struggling with this for over a week now.

Does anyone live in Lower Michigan who would be willing to swing by and take a look? I'd pay for gas and beer...

Heck, I'd by you dinner and sing you a tune if it gets the bike running.

 

exactly what I am going through right now

 

Resistor vs. non-resistor plugs: Some XJs came equipped with resistor plug caps so you don't want to use resistor plugs with those; using non-resistor plugs on a bike NOT equipped with resistor caps won't matter either (except you will transmit excessive electrical "noise.") If your bike is stock, I would use what it specifically calls for.

"gapped to .75"--- Millimeters? That works out to more than .029", which is on the "wide" side of the gap range. Since plug gaps widen as they wear, I would set them to the small end of the recommended gap range for your bike instead. And while you're at it, be sure all your plug caps are screwed on tight.

 

done and done. No effect

 

Just a thought, but have you tried spraying carb cleaner in the air box and see if it starts? I had what I thought were clean carbs, but the freakin' enrichments were still clogged.

If it starts with a bit of carb cleaner blown in there, then that is your problem.

 

just curiouse where your carbs are set at ? 2 1/12 turns out to start and did you bench synch it while you had the rack off?, just a thought through my minescule pee brain

 

Determine what element is missing!

Fuel, Air and Spark.

If you spray Starting Fluid in the Air Box and the Engine runs a moment.
You have a FUEL delivery issue.

 

Nope, won't even start with starter spray. Just keeps cranking til the battery dies...

However, I did find some sort of creature living in my fuel bowls. Not sure if this would cause the bike to not turn over, but I know it didn't belong in there.

I posted the video on my blog...

It LiVES

My pilot screws are 2.5 turns out.

 

Silly question, but do you have the choke on and verified that when it is on that it is opening up? Try that and open up the throttle while spraying in starter spray and if it doesn't fire up, then you know it is an issue with spark and not air/fuel. If it does start, then you're looking at a fuel delivery issue.

On a side note... an amoeba??? That's got to be a new one!

 

Yep, choke was on, and tried opening up the throttle, to no effect (other than a dwindling battery)

I may bench sync, just to be sure that the butterflys are opening as they are supposed to (though it started yesterday... can't see that changing..)

It acts like it's not getting spark, but I checked again tonight and you can see the spark quite plainly.

Since the coils are within spec, and I'm getting spark, it's got to be fuel, right?

 

I would think so, but the fact that the choke is on and the throttle is open when you're spraying starter fluid in makes me second guess that. You've used an ohmeter to check to make sure everything is within spec.

Cylinder compression? Engine flooding? Have you verified your float heights? Do a compression check first. Easier than pulling and taking the carbs apart *again*. :/

EDIT: I just thought, if you already have the carbs off... why not spray some a little starter fluid directly in and see if it briefly catches? DO NOT do this standing beside the bike. Stand in front and turn her over. That should eliminate a spark problem at least in theory.

 

If I do spray starter fluid, where exactly do I spray it? In a manifold?

What should I expect? Fireball? I'm assuming that's what's going to happen, since your instructions state don't stand next to it but in front.

I'll give it a try...

 

I would guess with that much air in the combustion chamber, that you might get a backfire or possibly a quick combustion flame (but nothing that is going to cause any damage if you only use a little. But yeah, give a quick shot inside each inlet boot.

 

If i do get a fireball, then this indicates spark, yes? Makes sense.

I need to do a compression check. But having the bike go from running great yesterday (albeit sync issues) to not running at all today is odd.

 

Oh, didn't know she was running yesterday, so yes... that would likely eliminate that, but it wouldn't hurt to try.

The engine should actually start briefly. A backfire or brief flame is just worst case senario and not likely. Better safe though. I've been singed before working on a car.

If it does start, then it's back to the carbs again... and the fun begins. Start with the float heights.

 

I'm not expert, far from it, but it sounds like your battery's dying too quickly. I had all kinds of problems until I put a new one, and it looked great on the voltmeter. Now that I have other problems, the battery never dies no matter how bad or long I work it. and yes I seen spark ground to the head bolt with the old battery. there's my 2 cents

 

That's certainly something to think about. This is a brand new battery though. Hmm...

I'm hoping the crud in the carbs was the main issue. I'll post more tomorrow.

If anyone else has any other ideas, I'd love to hear them. Also, if anyone in MI is interested in swinging by, I still have that altar set up.

 

I noticed on carbs 2 and 3 that the little port is blocked with.. plastic? Some kind of material. What is that all about? I can't drain the float bowls because of those. Do I poke a hole in them?