Just inherited a blaster that ran untill it got to my house (so he said) any how it will not start. tough to see any spark however I'm used to high energy ignition. It fouls the plug instantly so I removed the plug and cranked for a few seconds to clear out the cylinder. lots of fuel spit out so I removed the carb and found two reed valves caved in towards the carb. Replaced them but still fouling plugs. How can I check the intensity of the spark? or any other suggestions?
Wont start. possable weak spark?
- Thread starter blastervigin
- Start date
tap the side of the carb with a small hammer, in case the floats are stuck, then follow this electrical system trouble shooting guide posted by braaaptor.....................
Damn, man. I know how that feels. Electrical problems suck. Your intermittent spark problem is quite likely due to a bad ignition coil. Many times, the high-tension lead (heavy wire that goes from the coil to the spark plug) develops an internal break. Coils can also develop an internal short or open circuit. Either of these faults will result in an intermittent spark at the plug. The coil only fires when the bad connection happens to be made. Which isn't very often, as I'm sure your exhausted right leg can attest.
Do this: Turn the keyed ignition switch (if used) and handlebar switches 'ON'. Unhook the spark plug wire from the plug and remove the spark plug from the engine. Next, find that one-and-only orange wire that attaches to the coil. Unplug it, and go get your 12V test light. (You can buy one for about $ 15.00 at the local auto parts store, or Sears, or....).
Stab the plug on the orange coil wire with the pointed end of your test light. Ground the other end of the test light (with the wire/clamp) out against the engine. Be sure you have a SECURE connection. Now, kick the engine over and watch the test light. The bulb in the test light should blink once for every revolution the engine makes. In other words, the light should flash 'in sync' with the rotations of the crankshaft. This test will tell you whether or not you're getting the required 12 volt 'signal' from the CDI box to the coil every time the piston reaches TDC. If the light blinks steadily, replace your coil. It is defective. The CDI box is sending its 12V pulse to the coil, as it should, but the coil is unable to properly transform it.
Nothing, or an inconsistent blink of the test light, indicates that your ignition coil is not recieving its proper trigger pulse from the other components of the bike's ignition system. Time to pull out the ohm meter and do some resistance checks on the exciter and trigger coils. I'd also test the ignition coil for good measure, just to be sure that it is indeed still good. If these coils test OK (see a Clymer manual for the resistence specs), all connections are clean/tight, and you can't find any bare wires that are accidentally touching the frame, replace your CDI box. It can be ruled faulty if everything else in the ignition system tests good.
Damn, man. I know how that feels. Electrical problems suck. Your intermittent spark problem is quite likely due to a bad ignition coil. Many times, the high-tension lead (heavy wire that goes from the coil to the spark plug) develops an internal break. Coils can also develop an internal short or open circuit. Either of these faults will result in an intermittent spark at the plug. The coil only fires when the bad connection happens to be made. Which isn't very often, as I'm sure your exhausted right leg can attest.
Do this: Turn the keyed ignition switch (if used) and handlebar switches 'ON'. Unhook the spark plug wire from the plug and remove the spark plug from the engine. Next, find that one-and-only orange wire that attaches to the coil. Unplug it, and go get your 12V test light. (You can buy one for about $ 15.00 at the local auto parts store, or Sears, or....).
Stab the plug on the orange coil wire with the pointed end of your test light. Ground the other end of the test light (with the wire/clamp) out against the engine. Be sure you have a SECURE connection. Now, kick the engine over and watch the test light. The bulb in the test light should blink once for every revolution the engine makes. In other words, the light should flash 'in sync' with the rotations of the crankshaft. This test will tell you whether or not you're getting the required 12 volt 'signal' from the CDI box to the coil every time the piston reaches TDC. If the light blinks steadily, replace your coil. It is defective. The CDI box is sending its 12V pulse to the coil, as it should, but the coil is unable to properly transform it.
Nothing, or an inconsistent blink of the test light, indicates that your ignition coil is not recieving its proper trigger pulse from the other components of the bike's ignition system. Time to pull out the ohm meter and do some resistance checks on the exciter and trigger coils. I'd also test the ignition coil for good measure, just to be sure that it is indeed still good. If these coils test OK (see a Clymer manual for the resistence specs), all connections are clean/tight, and you can't find any bare wires that are accidentally touching the frame, replace your CDI box. It can be ruled faulty if everything else in the ignition system tests good.
R/R carb and got bike running. However now I have nothing more than an idle with wet oil from the exhaust and the dreded white smoke. Sounds like last rights time?:-/
It could be a crank seal, or possibly just the jetting being too rich. Check the air filter and make sure it is clean. An easy way to tell if the jetting is rich is to turn the fuel petcock off and then try revving the motor until it runs out of gas. If it responds and revs well right before it runs out of gas and dies, then you know that its jetted rich.
Will not rev at all. only idle. even with fuel on. I find it hard to believe that the amount of oil being produced is from the fuel alone. It drips from the ehaust and splattered on the wall as well as pooled on the driveway. must be from the crank or tranny? Now i'm not sure if it wont rev because of the new reed valves. they didn't look quite like the old ones.
I'd have to agree that it sounds like more oil than from just the premix, especially if it was enough to pool from the dripping. Sounds like crank seals most likely, never replaced them personally but from what I have heard on the site its not very hard to do. If you are worried about the reeds, post some pics of them so we can see what they look like.
Ok but will take a day or too to remove them. The difference was that the old ones had small flappers but covered the orifices. they had a border around it as if the flappers were punched like a cookie cutter in the middle. the new ones just had two big flappers but no border. if that helps.
i undstand, it sounds like youare describing boyesen power reeds which are 2 peices to regular one peice reeds like the stockers or say some boyesen pro series or some aktive reeds.
Sounds like the old reeds were dual stage, were they like these....Yamaha Blaster Vito's Carbon Flex Reeds 88-06 YFS200 : eBay Motors (item 200256536086 end time Feb-13-10 16:19:04 PST) ? The dual stage is just supposed to help with lowend some. The new reeds sound like normal reeds, so you should be fine.
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