KrZy8 down n out?

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dcarver

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For the last several days, noticed that KrZy8 was starting a bit slow, idle was fluctuating ~300 rpm, and mpg decreasing. Tonight's commute sealed the deal. Stopped to make a phone call, she stalled at idle. Fired back up, but wouldn't keep the fire unless 2k rpm held. Rode rest of way home, about 7 miles, slowly (yeah right) hoping it was bad gas - I had opened the aux tank about 20 miles earlier.

  • Checked aux fuel tank - clean, no debri, water, etc
  • Checked main tank, clean
  • Drained both tanks
  • Put known good fuel
  • Problem remains
  • Pulled tank, all plug wires tight.
  • Pulled #4 plug, clean,dry, looks good. (Other plugs look like the water bar need be removed to not strain plug wires, out of scope for working in dark tonight)
  • Run diagnostics - all looks good execpt an error code of 12 - crank sensor.. Hmm, this kind of makes sense.. Probably has a limp home mode? Not good for any one rpm range, but close enough to fire?
  • Clear the code via 52 and start/stop.
  • Code 12 does not come back. Arrgh.



  •  
  • Bike is popping, backfiring? at 1,200 steady rpm and on decel.
  • Hmm, putting my hand at exhaust end yields a *sticky* hand. No steam or vapor showing, but the result is sticky, somewhat glossy hands. Not wet - just a film of sticky that's more than obvious and new. Fortunately, I know the exhaust feel of KrZy8 as I routinely warm my hands after riding to work in the early AM with the exhaust. This sticky stuff is new. I'm thinking a blown head gasket and the sticky feel is coolant. The popping is due to lean mixture due to water in the combustion process.
     
    Any ideas or tests I can? Do you agree with my hypothesis?
     
    <crap>
    I start working on my 1979 KZ1300 and KrZy8 throws a hissy fit! :angry2:
    </crap>

 
Bummer to hear Don.

Hmmm. Check the battery terminals (doesn't explain sticky hand but then I don't know where your hand has been :p ).

Check your oil. Is it the same color, and or has it gotten foamy?

Also does the bike over heat (classic head gasket issue)?

I'd also check all the plugs, that's the best read on how the engine is running.

Clogged fuel filter?

Bad fuel pump?

Good luck, keep us posted.

 
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Bummer to hear Don.

Hmmm. Check the battery terminals (doesn't explain sticky hand but then I don't know where your hand has been :p ).

Check your oil. Is it the same color, and or has it gotten foamy?

Also does the bike over heat (classic head gasket issue)?

I'd also check all the plugs, that's the best read on how the engine is running.

Good luck, keep us posted.
Will check batt terminals.. but everything else is sat - voltage, lights, etc..

Oil - good call.. but if it's a head gasket leak why would oil get foamy? I'm envisioning a gasket blow out between water jacket and combustion cylinder(s), 2 and 3 (would explain both exhaust's being 'sticky')..

No overheat yet, and temp gauge still indicates.. (thinking water is still in the block surrounding sender)

Plugs - yeah, need to do, but pulling even #4 (greatest service loop, put a strain on the cap) - would want to pull the water bar first before pulling the others.. ?

All the plugs look the same? If your running lean should be some white chalky deposits on the effected cylinder
Don, only pulled #4 - the others have really wiring and I'm afraid it will pull the boot out of the wire unless I first pull the water pipe thingie..

 
Clogged fuel filter?
Bad fuel pump?
Both tanks look exceptionally clean - no debris or contamination I can see.

Fuel pump? Don't yet know - no pressure test yet.

Still - the 'sticky' exhaust has me intrigued. It has to be a clue? :huh:

 
It has to be a clue? :huh:

It was Mr's Forsithe, in the Library, with an Icepick.........Did I win????

Maybe a compression check might help or a leak down test.

Normally a head gasket will produce the white smoke exhaust, depending on how bad it is...If it's stalling should be pretty bad.

No other changes recently?

Bustanut didn't tip your bike over while you weren't looking? ( cause we all know you would never drop it)

 
Head gasket - coolant to combustion chamber.

If large gap, possible hydrolock. Es no bueno. Don't think this is the case, it most likely wouldn't run if was. Symptoms you describe don't fit.

Steam in exhaust. Coolant smell, taste, feel.

Air in cooling system. Listen for percolation. Look for low coolant level.

Compression check would be quickest method of diagnosis.

ALSO - Possible vacuum leak. Not as likely, but possibly. Would have to be a large one to affect engine to the extent you describe.

Just for grins, check the fuel injector rail for tightness. It's held in place by two M6 (might be M8, can't quite remember) screws. If it's loose, you could have vacuum leaks in two or more injector ports.

You have my number to discuss. Call me.

 
You don't need to remove the water pipe thingy to check the other plugs. I just changed all my plugs with it in place, no problem.

As to your issue, if the oil is not foamy (water in oil), and the coolant level is fine, then I wouldn't think head gasket. You need to check one of the plugs from cylinders 2 or 3. If they look extremely rich, then the sticky stuff from the exhaust could be unburnt gas. Does the exhaust smell rich? I'm thinking it could be the 2/3 coil or bad connection to the 2/3 coil. Don't disregard that error code 12, I think it is a hint towards the problem.

Got my fingers crossed for you that it's just a bad connection.

 
A coolant leak into the combustion chamber would give a "sweet" smell out of the exhaust while running. Napa has a Combustion Leak Tester (Part #BK. 700-1006) which uses a chemical that changes color from blue to yellow if there is exhaust gas in the cooling system. You need to run the engine with the radiator cap off and the engine up to normal operating temperature to use this kit. From personal experience it is accurate when the liquid turns yellow. Good luck I hope it is something other then a headgasket.

 
You don't need to remove the water pipe thingy to check the other plugs. I just changed all my plugs with it in place, no problem.

As to your issue, if the oil is not foamy (water in oil), and the coolant level is fine, then I wouldn't think head gasket. You need to check one of the plugs from cylinders 2 or 3. If they look extremely rich, then the sticky stuff from the exhaust could be unburnt gas. Does the exhaust smell rich? I'm thinking it could be the 2/3 coil or bad connection to the 2/3 coil. Don't disregard that error code 12, I think it is a hint towards the problem.

Got my fingers crossed for you that it's just a bad connection.
+1

 
Lift the plug wires by the boot, after giving them a quarter turn either direction to "break" them loose from the plug. Don't pull on the wire alone, or you'll get just the wire, although that's not the disaster it sounds like.

Absolutely no reason to pull the water pipe just for the plugs. The PAIR system will be in the way, though!

The bike won't run at all if conditions exist to set a code 12, so that may have come from something that happened some time back, turned the bike on without everything hooked up.

 
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Change yer blinker fluid, Don. Duh - even I know that.

And that sticky stuff... Well, you did ride with Bust back in August. Maybe he 'did' something.

:p

Got my fingers crossed for you that it's just a bad connection.
Gunny!

 
I did the same for Don as I did you Andy.. Pissed in the tank several times, and railed away on the tailpipe. ;)

I shit in bears tank though. Wonder why he's still running?

I'm good like that :p

 
Head gasket - coolant to combustion chamber.

Steam in exhaust. Coolant smell, taste, feel.

Air in cooling system. Listen for percolation. Look for low coolant level.

No steam in exhaust, exhaust smells 'normal' FWIW.. then again, my sense of smell is weak.

Compression check would be quickest method of diagnosis.

Borrowing a bud's pro comp check kit tomorrow.

ALSO - Possible vacuum leak. Not as likely, but possibly. Would have to be a large one to affect engine to the extent you describe.

Like if the Audiovox 'vacuum accumulator' split a seam or something?

Just for grins, check the fuel injector rail for tightness. It's held in place by two M6 (might be M8, can't quite remember) screws. If it's loose, you could have vacuum leaks in two or more injector ports.

Will do.

You have my number to discuss. Call me.

Thank You Hal!

You don't need to remove the water pipe thingy to check the other plugs. I just changed all my plugs with it in place, no problem.

I think the spark leads are routed non-stock, they run under the coolant pipe. I don't see how there is enough service loop given the long cap boot and subsequent distance required to clear the plug and head walls... How are your plug wires routed - over or under the pipe?

As to your issue, if the oil is not foamy (water in oil), and the coolant level is fine, then I wouldn't think head gasket.

Check for foam via the oil window port or by draining?

You need to check one of the plugs from cylinders 2 or 3. If they look extremely rich, then the sticky stuff from the exhaust could be unburnt gas. Does the exhaust smell rich? I'm thinking it could be the 2/3 coil or bad connection to the 2/3 coil. Don't disregard that error code 12, I think it is a hint towards the problem.

I know that 4 is throwing a good spark - and I ran the diag to spark the plugs - w/o looking at the plugs of course, but the sound heard for both banks was identical.

Got my fingers crossed for you that it's just a bad connection.

A coolant leak into the combustion chamber would give a "sweet" smell out of the exhaust while running. Napa has a Combustion Leak Tester (Part #BK. 700-1006) which uses a chemical that changes color from blue to yellow if there is exhaust gas in the cooling system.

My sense of smell is limited, always has been. Given that, I can't detect any change. Hey, I know, I'll sniff the DL650 then go sniff the FJR. That may be helpful. I see the Napa part is about 50 bucks - not bad. Thanks for the hint.

Lift the plug wires by the boot, after giving them a quarter turn either direction to "break" them loose from the plug. Don't pull on the wire alone, or you'll get just the wire, although that's not the disaster it sounds like.

I did the quarter turn thing, all caps are seated on plugs.

Absolutely no reason to pull the water pipe just for the plugs. The PAIR system will be in the way, though!

My PAIR has been removed can capped. However, I do have an Audiovox cruise control stuffed into the compartment just ahead of the plugs. That maybe why I don't have much if any service loop.

The bike won't run at all if conditions exist to set a code 12, so that may have come from something that happened some time back, turned the bike on without everything hooked up.

Now that's something very good to know - it doesn't have a limp home mode? If true, and you seem to know your stuff, then I can eliminate the crank sensor/circuit. Am I right to assume that it would throw the code again if the problem existed, after first clearing an existing code?
 
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