All of the sudden, won't start 1990 Trail Boss 350L
 

Well fella's, I'm stumped. As I've mentioned on here before I've acquired a 1990 Trail Boss 350L. I did a full top end rebuildamong other things and got it running. It's been running just fine.

It had been sitting in the garage for about 2 weeks when I noticed a puddle of fuel underneath. Long story short, the petcock was turned off, but failing which allowed fuel to free flow into the carb which began to fill the air filter box and drain out of the air filter box drain hole. Once I figured that out, I pinched off the fuel line until I could get a replacement petcock. I replaced the petcock today and put everything back together I decided to start it up since it had been sitting for a couple weeks. It would not start. I began getting a lot of fuel/oil mix leaking out of the exhaust ball-type connections. Is it possible that all that fuel that was leaking past the petcock and into the carb/engine caused my rings to go bad or crank case seals, etc to be blown when I tried to start it? I pulled and cleaned the spark plug, tested for fuel and spark which were good. I had not tested compression yet though. I haven't put 20 hours on it yet since the top end rebuild. Also, I can't get the oil pump out to replace it as the dang screws are stripped out, so I was just pre-mixing the fuel/oil until I can figure a way to get those screws out to replace the oil pump (it is definitely not working). if I mixed the oil/fuel too strongly could that have contributed to my issue as well?

Thoughts?

Roger

10mm crank case drain screw at the bottom of the engine. Drain it,put the plug back in. Pull the spark plug out,hold the throttle wide open and pull the recoil several times to clear any remaining fuel. Put the spark plug back in and hold the throttle wide open again. May take a couple times for it to crank.I've had to do plenty like this. This short period of time shouldn't have hurt the crank seals. Fuel valves can go bad as you've found out,but if you haven't replace the needle and seat in the carb,might be a good time to do it also.Always turn the fuel off on the old 2 strokes when through for the day. On the soft headed oil pump screws is where a hand impact driver can break them loose with no trouble. I've had this Snap On set for years,but plenty of cheap ones around 15 bucks on ebay,Harbor Freight that can do the job.Good tool to keep in the tool box.http://www.ebay.com/itm/SNAP-ON-Impact-Driver-Set-3-8-Drive-Reference-208EPIT-/261413928856?pt=Motors_Automotive_Tools&hash=item3cdd7bff98&vxp=mtr

Yeah, if it's one thing I drill into my kids heads with their dirt bikes and quads is to absolutely turn off the petcocks at the end of their riding. I"ll do what you suggested tomorrow. I just hope I didn't turn the engine over too many times to cause any other damage.

As for the soft headed screw. I do have one of the hand held impacts like you suggested (although not nearly as nice as Snap On), I just couldn't get on this particular screw with room to hit it and turn. But I did order some of the Screw Grab Friction Gel and hope it works as half as it good as it claims too from the old infomercials years ago. Considering they still sell it I am going to assume it must have some usefulness to it. Ordered it tonight, but I can continue to premix the fuel until then.

I'll update tomorrow (keeping my fingers crossed)

Thanks again OPT

OPT, Can you describe the 10mm drain bolt location? I have removed the skid plate and looked all over the bottom end but am not seeing a 10mm drain or anything that looks like a drain other than the trans fluid and main oil drains.

Found it......disregard

:) Kinda hard to see in between the holes of the skid plate.I just used a 1/4 inch drive short 10mm socket and a long extension to drain this plug. Dirt Cheap Yamaha, Honda, Arctic Cat & Polaris OEM Parts & Accessories – Cycle Parts Warehouse

It was hiding behind the starter wire. I am up and running now. Who says you can't learn something new as an old dog like me.....lol