Hi I'm new to the forum. The neighbor kid brought over his 2000 blaster saying it wouldn't start and was getting no spark, I put on a new coil, stator & CDI and am getting a great spark, it still wouldn't start I pulled the carb and cleaned it and replaced the reeds (one was cracked) with some vito's dual stage reeds and still nothing but an occasional fart and backfire, It appears to be getting fuel as the plug is getting wet, compression is at around 150 psi, I am getting a little smoke coming out of the exhaust but still not starting. I am running a bare bones harness (NO headlight , TORS, etc) Only thing I havent done is a leakdown test, (but usually with a crank leak you usually run, just not well) I have good experience with 2 strokes but am at my wits end with this one, any help would be great.:-/
At my wits end
- Thread starter chewyfishcake
- Start date
just a few thoughts i haven't seen covered.....
is the keyway on the flywheel and not slipped time ?
flywheel nut torqued to specs ?
have you tried a new plug ?
sometimes a fouled plug will spark great when held against the head to test, but not when under that 150psi of pressure.
a plug can foul instantly, try another one
pull the pipe off the cylinder and kick it, a clogged pipe/silencer, or the cases flooded full of fuel will not allow it to start.
watch for fuel spewing out to detect flooded bottom end.
btw...welcome to BF !
is the keyway on the flywheel and not slipped time ?
flywheel nut torqued to specs ?
have you tried a new plug ?
sometimes a fouled plug will spark great when held against the head to test, but not when under that 150psi of pressure.
a plug can foul instantly, try another one
pull the pipe off the cylinder and kick it, a clogged pipe/silencer, or the cases flooded full of fuel will not allow it to start.
watch for fuel spewing out to detect flooded bottom end.
btw...welcome to BF !
Running a #150 for the main with the airscrew @ 1 1/2 turns out. I checked the flywheel key it looked good but I replaced it anyhow, I didnt torque the flywheel nut to spec though. I did remove the pipe and it had quite a bit of fuel in it replaced it and still getting the same results. It still hardly pops even with starting fluid. Could the timing have gotten thrown off somehow? I did hook up my timing light and its firing a few degrees before TDC. I also tried airing out the motor by removing the reed block, putting the piston @ TDC and letting it sit a couple days still not getting squat.
Also tried a couple of plugs. The quad ran great up until the ignition troubles, which leads me to believe something is goofy there. My son is a certified tech at a Yamaha dealer and is also stumped.
No typo, Its a #150 Keihin jet. The carb is an OKO 30m, also a pro circut pipe & silencer. What would be a good baseline jetting for this?
No other engine mods that I am aware of. Like i said I am running a bare bones harness and getting a healthy spark. This machine ran great up until the spark issue.
Um... a #290 or #300 i think
Wait for the jetting experts to answer - But until then, dont try to start it with the #150
Wait for the jetting experts to answer - But until then, dont try to start it with the #150
Ive worked with a lot of keihins on 125 & 250 MX bikes and a 150 main and 42 pilot seems about right to me for this machine. It seems like the OKO is a keihin copy, Maybe i'm wrong.
You have possibly flooded it.
Turn the petcock off, drain the float bowl, take out the spark plug, and with the throttle wide open and kick 20 to 30 times to purge the crankcase of accumulated fuel.
Replace the spark plug and try to start it.
Turn the petcock off, drain the float bowl, take out the spark plug, and with the throttle wide open and kick 20 to 30 times to purge the crankcase of accumulated fuel.
Replace the spark plug and try to start it.
The stator I put on is an aftermarket W/ adjustable timing, I did however mark the pickup coil position and position it there. I will try draining the carb, removing the plug and pipe and kicking it dry. Makes sense since the kid told me he towed behind another quad forever to try and get it started, without spark that fuel has to go somewhere. Let you know tomorrow how that works.
Not an expert advice but did you make sure the key is turned to on position/and switch is on the run position? Sometimes we overlook the simple things
After checking my spark again it doesnt really seem as strong and consistant as it should be, I think i will try switching out my coil. Does anyone know what the resistance of the plug cap should be 5K or 10K? Try my stator after that and of course check all of my connections and grounds. Should there be a grounding wire going from the frame to the engine?
ohm specs of all the ignition components are in the troubleshooting section of the manual, it'd pay to download it........
http://www.blasterforum.com/general-support-17/downloadable-yamaha-blaster-manual-17325/
no ground wire needed from frame to engine
http://www.blasterforum.com/general-support-17/downloadable-yamaha-blaster-manual-17325/
no ground wire needed from frame to engine
Got er runnin, The coil tested out good as did the power coil and pickup coil and still got a crappy spark, I got a stator rebuild kit from moose anyway and installed it on the stock stator plate, put it together and it started on the 1st kick. Must have been a broken wire or somthing on the 1st stator I bought...warning dont buy electrical parts from Ebay!!!
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