just got a Xplorer 300 and need some help here. It gets fuel and has a strong spark an decent compression of 120psi but yet it wont fire.
I took the carb apart and cleaned it (probably my 50th 2-stroke carb I have taken apart, I'm no expert but this isn't the first engine I've worked on) cleaned the fuel tank and put in new gas and nothing!
floats look good, fuel gets to the plug as I can see it gets wet. Electric starter doesn't work so I am wearing my arm out pulling the rope. What am I missing guys? The slide adjustment screw on the carb is 3 turns out from bottom and smaller screw is 1 and 1/4 turns out from bottom. Any ideas, suggestions? thanks!

 

Pull the drive clutch and check the crank seal for seeping. Could be loosing compression in the bottom end.

 

Thanks for the response. Is that a visual check on the seal or is there a way to check it with some pressure etc...? My experience is pretty much limited to taking carbs apart and top end rebuilds so, the simple stuff. Getting into a bottom end and rebuilding it is over my skill limit.
Guess I'll type in "pull drive clutch" and or "replace crank seal" in search and see what happens unless you can show me where the Link might be.
Do you think it will run with 120psi or does it need more?
Anyway, thanks for the suggestion.

Didn't mean to "double post" but I couldn't find the "ask an expert' area and thought maybe you guys might guess that. Is there an easy way to find it? In the forum columns there is no "ask an expert" tab and I typed in "ask an expert" in the Search area and it didn't show up.... . I just joined a few hours ago and I'm not that computer savvy.

 

An engine has to have good top end compression along with a good bottom end compression,that is the crank seals have to hold the air/fuel/oil mixture in the crank case under pressure and shoots this mixture up the transfer ports to be ignited. This may or may not be the problem,but it's one that does happens if the seals leak. Best way is to do a leak down,but involves blocking off the exhaust,installing an intake adapter and a small pressure gauge. Most hold 7psi with no drop. Sometimes seals can show signs of visually seeping,at times I've found the seal on the clutch side popped out. Again may not be the problem,but check as a last resort. Another thing to do is pull the black wire from the reverse limiter module under the front panel as it can short out and retard spark. Just leave it unplugged. Item #27. Dirt Cheap Yamaha, Honda, Arctic Cat & Polaris OEM Parts & Accessories – Cycle Parts Warehouse When cranking also hold the throttle wide open to see if it may clear any excess mixture in the crank case.

 

Thanks for the advice! I'll try those ideas soon as I wake up.... I can make the carb and exhaust block off plates alright but getting an accurate 7psi gauge will be a new one for me. Mine are just tire gauges that go that low. Do you mean it will hold 7psi overnight or for a few hours?
Thanks for the diagram....that helps.

 

This is what's involved and tools needed in a leak down test .

 

Thanks OPT. Looks do-able.