I recently bought a 94 fourtrax. Sold non running, got home adjusted carb fired first kick. Was fire for a few days and then it stopped firing over. Got my starter working and ran into every time I gave it gas to try to get it to fire, it would backfire a huge poof out of intake. Exhaust is pushing out air. Has enough compression for me to stand on the kickstart, and more spark then Clark grisswald. So timing right? Checked timing with the cam gear method and the inspection, seemed perfect. Valves? Valves were slightly off, adjusted, same exact issues. Currently won’t fire off spray with carb off, plenty of spark and timing seems fine. What the hell could be the issue? Timing chain is tight. Only thing I thought was left but it looked fine. Any helpful hints?
94 Fourtrax… thought these were simple
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Forgot to say, starter spins with power and cranks fine until any gas is introduced. Valves aren’t bent at all. Plenty of oil. New cdi box, plug, wires, and carb.
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remove the spark plug, does it come out wet?
Im willing to get it running!
Im willing to get it running!
spark plug is dry, and when pulled with the boot in has a ton of spark
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so if you pull the plug out after trying to crank it and it is dry.....you are not getting fuel into the spark plug.
remove carb and clean jets, float.
remove carb and clean jets, float.
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how many cc?
i currently have carb off trying to ignite with spray to cancel out the carb. The carb is clean though and floats and everything working well.
300 4x4
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you will need to check cylinder compression with a gauge and get the psi reading.
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what does the spark plug look like, can you post a pic?
that will be next but has a ton of pressure with plug pulled and kickstart takes a lot to kick over. Really don’t think it’s compression, I parked it, next day it fired first kick then stalled from being cold and this developed.
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choke works?
I’ll send a spark plug picture tommorow it’s brand new though. Only thing that is puzzling me is do these have spark timing or do they fire every stroke?
Yeah but I’m having the backfire problem before any fuel wants to turn it over. I can’t give it more then 1/8th throttle before it backfires hard enough to have me checking for bent valves.
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cdi controls spark.
i have great spark I just didn’t know if they were timed or it was a key way in stator
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you could check timing with a timing machine
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if you follow the troubleshooting steps I posted, and you go by off what you think, the next step would be to use choke then pull the plug again. if it's still dry, it is not getting fuel.
if you used a lot of starter fluid, it may be flooded by now.
if you used a lot of starter fluid, it may be flooded by now.
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