Power Valve Issue (Starting Issue).

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Kenny
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Power Valve Issue (Starting Issue).

Post by Kenny »

Hi Guys,

I have a KDX 250 1994, Its been riding great but for the past two days, can't get it started. Did most of the basic checks (Spark plug is fine, fuel line fine, carburettor was cleaned, air filter fine, fuel mixture fine, even thought I would use the occasion to change oil). There is definitely compression, I took the exhaust out and could see that the piston is moving up and down very easily and rings are fine. It is not a electric issue either, I think. Every time I kick (choke on) it idle for a second and dies, if I press the throttle all the way down and keep it down, it "idle" for a while then dies.

I noticed smoke coming out of the power valve shaft lever casing, so I took it off and I notice that there was the end circlip on the shaft that was missing. So the valve operating rode that opens and close the exhaust valves has two circlip on each side of the round thing. The circlip facing the engine is there, the one facing out is missing. Could this result in the bike not starting (i.e not getting enough compression because exhaust valve are not closing) or is the starting issue something completely different ? I will attached a few picture so you can understand what I am talking about.

Some help on the matter would be greatly appreciated.

Regards

Kenny.
Last edited by Kenny on 10:21 am Apr 08 2016, edited 1 time in total.
david
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Re: Power Valve Issue.

Post by david »

Power valves should not cause a starting issue. Good fuel, proper jetting, good reed valves, properly tightened and sealing intake gasket and cylinder base gasket. It sounds to me like you have a fueling issue.
'81 KDX 175
'90 KDX 200
'07 Vulcan 2000 Classic LT (totaled 4/25/15)
'82 Honda GL500 (sold)
'96 ZXi 1100 JetSki
'98 STX 1100 JetSki
rparrish08
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Re: Power Valve Issue.

Post by rparrish08 »

Unless you do a compression test there really isn't any way to confirm adequate compression. I'd start there. Have you tried push starting? Have you checked the reeds?
I have fought the good fight, I have finished the race, I have kept the faith. 2 Timothy 4:7
Kenny
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Re: Power Valve Issue.

Post by Kenny »

Thanks guys. I have tried to push start it and nothing happens... Better result with kick starts. I havent checked the reeds yet though but might take them of tomorrow and see. Its only the intake valve (by the carb) that i can check right?
Ill try and check all petrol limes as well.
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Re: Power Valve Issue.

Post by rparrish08 »

Correct. Just pull the carb and intake boot and the reeds are right there. Have you confirmed spark?
I have fought the good fight, I have finished the race, I have kept the faith. 2 Timothy 4:7
Kenny
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Re: Power Valve Issue.

Post by Kenny »

Yes I have. Defiantly good spark.
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Re: Power Valve Issue.

Post by rparrish08 »

It sounds fuel or air related. Or possibly timing, have you checked the stator and flywheel to see if they've slipped. I've had this happen with a flywheel. Woodruff key sheared and it took me an entire afternoon to figure it out.
I have fought the good fight, I have finished the race, I have kept the faith. 2 Timothy 4:7
Kenny
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Re: Power Valve Issue.

Post by Kenny »

Thanks man, I'm going to the hide in the garage now until that bloody thing starts...
Will keep you updated.
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Re: Power Valve Issue.

Post by rparrish08 »

Good luck
I have fought the good fight, I have finished the race, I have kept the faith. 2 Timothy 4:7
Kenny
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Power Valve Issue.

Post by Kenny »

Hi everyone,

Its been a long week and still no luck. I don't know what to do anymore. I will just run through all the operations I have done to see if we can diagnose something here...

Changed spark pug and check for spark
Check fuel line to carb - All good
Take carb off and clean properly, took jets off and clean needle, air-fuel mixture screw clean, float off and cleaned all.
While I took the carb off I noticed that the carb boot (between engine and carb) was torn where the hose clamp was tightened (a good 50mm tear) so I saw that a new one was about 100$ which I can't afford right now. I got the whole boot sprayed with rubber at a garage, did a great job and I believe that issue is sorted
Took the reeds off and cleaned them, everything looked good there
Put everything back together

Cleaned and oiled air filter

I try to push start it for a while and not starting

Tried to kick start it and no luck either, it sounds like it wants to start but just can't get it to idle for more then 2 seconds... If I kick softly (i.e not creating explosion) two three time then kick properly it idles for longer then dies...

Im highly annoyed not being able to solve this problem and don't want to take it in to a garage quite yet so more help would be appreciate ?

Could I have a sudden compression problem, the bike was starting without any trouble before it decided to be a pain in my rear. The only think I did after stopping the bike and storing it away is that I gave it a good wash under the hose pipe... Then stored her in the garage and the next morning not starting ...

Anything from your side that could help ?

Regards

Kenny.
rparrish08
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Re: Power Valve Issue (Starting Issue).

Post by rparrish08 »

Sounds like water in the fuel. Put fresh fuel in it and see where that takes ya.
I have fought the good fight, I have finished the race, I have kept the faith. 2 Timothy 4:7
Kenny
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Re: Power Valve Issue (Starting Issue).

Post by Kenny »

Ja thats what I thought originally and then put new fuel in. But I didn't empty all the lines and carburettor before putting new fuel (only emptied the tank)... Will try and get everything dry again and put new fuel ...
Kenny
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Power Valve Issue (Starting Issue).

Post by Kenny »

Hi all,

So after putting new petrol in the tank, and checking all line and carb once more, The bike still wouldnt start, still exactly same issue.

In a desperate attempt, I took the alternator (left side of engine) cover off just to see if the coils were fine... Although i defintly had a spark, i thought there might have been a short circuit as soon as higher voltage was created. As soon as i took the bottom bolt off, water came pouring out of the casing, i suspect it came from when i washed the bike... By the time I came to that stage night had fallen so havent tried to dry the all assembly yet but i suspect that my coils are wet and once high voltage is created by kicking, the short circuit shuts down my spark plug hence not starting (well i hope thats the problem anyways...)
Tommorron i will blow the water off and let it dry in the sun, and hopefully that will solve the problem
If you have any further advice, it would be appreciated.

It would make sense since the only thing i did after my last ride is washing the bike, and the next morning it started and died after a minute or so, i suspect the spinning got water all over the alternator and then the short was created, being in the casing it was unable to dry, once again i hope thats the problem....

Regards

Kenny.
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Jaguar
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Re: Power Valve Issue (Starting Issue).

Post by Jaguar »

check for rust at the stator coil mounting plate since that contact area is the return ground path for the hv coil and spark plug
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rparrish08
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Re: Power Valve Issue (Starting Issue).

Post by rparrish08 »

I'm rooting for ya buddy. Sounds like you're headed in the right direction.
I have fought the good fight, I have finished the race, I have kept the faith. 2 Timothy 4:7
Kenny
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Re: Power Valve Issue (Starting Issue).

Post by Kenny »

Hi everyone,

I can't wait for the day, I come to this topic to say thank you and everything is sorted but today is not this day...

I have left the bike with the stator/coil cover open in the sun for the past two day, been very hot. But still no success I believe it is better, the bike fire two three time before it dies now at least but still no starting.

I am not able to take the flywheel off due to the lack of tool (no puller) only have a bearing puller and too scared of breaking the wheel now...

So I still think that their is water trapped in the electrical system due to the fact that its trapped in the flywheel...
What other options do I have ? Spray Q20 ? Hair drier ?

Kind regards

Kenny.
david
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Re: Power Valve Issue (Starting Issue).

Post by david »

I would order a flywheel puller, that way you can clean, dry, and inspect everything properly.
'81 KDX 175
'90 KDX 200
'07 Vulcan 2000 Classic LT (totaled 4/25/15)
'82 Honda GL500 (sold)
'96 ZXi 1100 JetSki
'98 STX 1100 JetSki
rparrish08
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Re: Power Valve Issue (Starting Issue).

Post by rparrish08 »

david wrote:I would order a flywheel puller, that way you can clean, dry, and inspect everything properly.
+1
I have fought the good fight, I have finished the race, I have kept the faith. 2 Timothy 4:7
Kenny
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Re: Power Valve Issue (Starting Issue).

Post by Kenny »

Hi everyone,

Things are getting worse this side, pulled the flywheel off and now turns out that everything was fine in there but the problem comes from my pulser coil, too much resistance, I get 500Ω... I sent it to a garage now and he said that was the problem and I should get a new one.

After phoning a Kawasaki representing in SA, the part in not available in stock, 3 to 4 weeks to get and over 250$..
Does anyone has any other solution especially since Im not even sure that that is the only problem, scared the CDI is also buggered.

Any help? such a stuff up, how does that pulser coil can die suddenly without notice? Water damage? or is it when I sprayed Q20 on the coils ?

Regards

Kenny.
ohgood
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Re: Power Valve Issue (Starting Issue).

Post by ohgood »

Kenny wrote:Hi everyone,

Things are getting worse this side, pulled the flywheel off and now turns out that everything was fine in there but the problem comes from my pulser coil, too much resistance, I get 500Ω... I sent it to a garage now and he said that was the problem and I should get a new one.

After phoning a Kawasaki representing in SA, the part in not available in stock, 3 to 4 weeks to get and over 250$..
Does anyone has any other solution especially since Im not even sure that that is the only problem, scared the CDI is also buggered.

Any help? such a stuff up, how does that pulser coil can die suddenly without notice? Water damage? or is it when I sprayed Q20 on the coils ?

Regards

Kenny.

hte pulser coil is JUST a coil. you can re-wind it in your garage in thiry minutes, with wire from ebay/amazon. if the coil is actually bad, that's what i would do.
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