99 ZX 600 bog/cutting out

[Fox]

I'll do my best to explain what the sleds doing, kind of all over the place.

left the truck, made it about 10 miles before it just died going down the trail, checked plugs..looked good..wouldnt start untill choke on half, then ran great again for a few miles, bogged hard and shut down. got it running again with a very hard bog, wouldnt even pick up rpms over 4,000. Pulled airbox, checked fuel lines and carb boots, all looked good...ran great for a few minutes, great power, and then bogging hard, shut down and wont start. ended up towing it out of the hills. below is a list of some of the things it was also doing.

idle at 4k, turn choke on half, drops to 2k

also noticed before it died the last time, it would be idling at 4k, you'd throw the track to the side and the rpms would drop down to 2k.

Thank you for any help or ideas on this one, trying to avoid a trip to the service part of the dealership.

 

[Devilmanak]

Carbs need to be gone through, sounds like junk plugging up the jets.

 

[mgeary07]

Id lean towards CARBS too. Gas goes bad quickly and jets can easily be clogged. If youre riding in deep powder which is going over the hood, check your intake vents by the windshield to make sure theyre not starving the engine of air.

Hope this helps!

 

[Fox]

Anyone know where theres some info/reading on the web for cleaning these carbs or is it pretty easy if you just keep track of it?

Thanks again for any info!

 

[Ox]

I'm wondering about fuel pump. ???


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[kingballerkustoms]

Clutch side Crank seal.Pull the clutch off,pull the seal,and replace it.Problem solved.when the seal is bad the motor will suck air threw the seal,and bog the motor down.In most cases the sled won't even start unless you hold it wide open and pull it over.had it happen dozens of times

 

[Fox]

I'm wondering about fuel pump. ???


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Fuel pump was just replaced last season..still could be though..

Im heading out to tear into this thing right now...i'll keep you guys posted

 

[Fox]

Carbs were all spotless clean, couldnt find junk in anything...

It seems like it has to be a fuel issue somehow, sense it will run great for awhile then bog out..get it started back up, runs flawless then bogs out...not a consistant problem.

 

[Fox]

checked the seals, they all tested good, no change in rpm or anything. still idle very high, around 4k, if you shake the sled it will idle down to around 1800..or it dies. just standing on it shifting side to side. once you stop it idles way back up..

any thoughts on this one?

 

[Ox]

A plugged vent line to the gas tank could doo the same, but not nearly as quickly as your issue seems to pop up I wouldn't think. MAYBE if tank was CLEAR full?

Also - if gas tank clear full, fuel pump less likely to be the cause.


Have you cleaned out all the ratts nests in the exhaust? Does it sound muffled at all?

Choke cable retracting fully? I have had the cable wear through the rubber and then start to rust. Then the cable not release properly. When it bogs out - is it a rich bog?






EDIT:

Went back and read original post and see that you put on 10 miles first. Have you opened the gas tank cap since then? Mud daubers like to fill vent lines up.


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[turbolq4]

maybe the pickup line in the tank is broken. I have a 700 ZX that had some trouble with the pickup. Drain the tank, take it off the sled and remove the entire line that goes into the tank and make sure everything looks good and is clean while you are in there

 

[Fox]

Tried the vent tube, ran the sled without the fuel cap on, no change.

checked the feed from the fuel tank, pulled line on front of fuel tank to see if it was free flowing, fuel came out real free, let it flow out about a half gallon and no change in volume.

I cant put my head around what would be changing when you shake the sled to make rpms drop..and if you keep doing it, it will totally die...

 

[Ox]

Pulse line from the block to the pump hard/cracked?


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[BU1]

Carbs were all spotless clean, couldnt find junk in anything...

Don't take this the wrong way, but did you remove the pilot and main jets for cleaning, or just look at them while still installed?????????

 

[Devilmanak]

Along with that, did you take a good look at the floats/valves? Kinda sounds like stuck or bad valves also.
I had a 99 440 that did similar things, drove me bat crap. I even went to the point of riding with a timing light strapped to my bars to try to figure it out. I cannot remember exactly what it was, but it was carb related and I was kicking myself for not figuring it out sooner, as it was pretty easy. Actually, now that I think about it, I believe it was the fuel pickup. I think someone already mentioned it, but those brass filter/pickups were notorious for falling off the fuel line in the tank. When that happens the pickup line floats around in there and sucks air when riding. I finally wire-tied mine onto the line to solve the problem permanently. Without a clear tank it would be hard to see, but easiest thing is to get the gas low or elevate the front end and yank the line out of the rubber grommet on the tank. Pull it out, and see if the pickup is still on it. If not, fish it out of the tank and reattach.
Chris

 

[Fox]

found cracks in the pulse line before we rode it the first time, so its brand new as well.

carbs got torn down all the way when cleaned.

I did find that when i unhooked the small lines on the left sides of the carbs that go to the dpm that the dieing when shaking went away..hooked them back up, shake the sled and it dies. Tested the solinoid in the end of the dpm, it tested good. unhooked the air line that goes from the dpm to mpem and the sled runs great. Still not really sure what any of this means..where is the dpm suppose to bring air in from?