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starts, but then dies; yamaha radian

11390 Views 9 Replies 5 Participants Last post by  jhutchy
ok, i have a 1990 yamaha radian 600. yesterday was riding fine...figured some water got in the tank, poured some seafoam in to remedy that and it seemed to work..revved up fine, nice and crisp. no problems whatsoever. today, i go out there, start it up, and its idling..i try to rev it, and once again its acting as if theres water in the fuel...the acceleration is very slow and sounds labored. it eventually dies, and now when i start it, it will start, idle for about 2 seconds, then die. but it will start again, just keeps dying. changed the plugs, they turned out to be very worn, but i still have the same problem. yes, gap is correct according to sticker on bike, between .6 and .7 mm. poured fresh gas in the tank to dilute, should that be a problem, along with more seafoam to dissipate water, again if that was the case. im starting to suspect the coil or ignition module, whatever it is. fuses are good. any ideas? maybe someone has specs for resistance tests on the coil and/or ecm or ignition module?? thanks
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Try this first, drain all the gas out of the tank and carbs. There are screws on the bowls on the carbs you open up to drain them, it should come out the overflow hoses. Replace with fresh gas and try it out. If yours has a fuel filter replace it. If your bike has a PRI or Prime position on the fuel valve put it on that. If it still acts up open the gas cap and run it with the gas cap off. If that fixes it it means your cap isn't venting.

If the fresh gas, differnt position on the valve, no gas cap and fresh filter and whatnot doesn't help you'll have to dig deeper.
ive actually tried opening the cap and putting it on the prime position..fresh ags doesnt seem to be it. but let me know what you think of this....i sprayed some starting fluid on the intake boots, and i noticed some cracking...when i was cranking, it seemed as though the fluid was pulsating in and out of the best theory so far is that the intake boots arer leaking, causing it to lean out, which is why it wont stay running. when it is running for that brief period, when i pull the throttle, the engine sound changes and it bogs im thinking its a vac leak. plausible?
Could be. It's awful tough to try and figure out what's wrong when you're not looking at it though. This is the part that sucks about the internet, ya can't be there to give a guy a hand.
amen on that...well, it seems i found the problem. seems it WAS water in the tank. i bit the bullet and started taking it apart, removing carbs and so forth. noticed some water residue just inside the intake boots...first red flag. set the tank to drain into a bucket and noticed it was cloudy, kinda milky. i thought i remembered gas looking that way when mixed with water. let it run for a bit, almost filled a 2 gallon bucket. started to run clear, and i drained the carbs...fired it up and after some running, she was back to normal it hopefully that problem is fixed..from now on, she stays covered!!! lol we've been getting ALOT of rain here in north texas, an unnaturally large quantity, gonna check the record...but i think that and the above average humidity is responsible for this mishap. i appreciate your input guy
Wow damn! That is a pile of water.
ohhh yeah...finally found the info i was looking for. from may 1st to june 30th, we've got a record rainfall of 19.44 inches, whereas average rainfall for may and june is 8.6 inches....that sucks. lol
radian same problem

Hi all,Similar symptoms. Running fine then poops out. I don't understand the cap vent design. One manual says make sure the vent in the cap is not plugged...what vent in the cap? I cleaned it, inspected it looks Ok. I'll try the open it up when it sputters idea this weekend. I'm going to have to trouvlewshoot the whole bike.....compression test, then spark check. If all that's Ok I'll plan on pulling the tank and carbs over the winter and pray to the Yamagods that it doesn't **** out on me next spring. Anybody have anymore TANK VENT/CAP stories? Let me know if you want to see some pics...
radian problem

I have a 86 radian...having a idling problem...what is the vacuum suppose to be at the intake hose running to the petcock... the vacuum is fluctuating from sucking to blowing not a steady that on all 4 intake boots..have had the carbs done...could the valve adjustment be a problem...are they adjustable? water in gas garage me nuts
xman, did you ever get yours to idle correctly?
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