Bike won't start - Carb or too much oil prob?

[3dmxr]

A friend of mine has an '01 YZ250F that has been sitting around for about a month. He came up to ride and before we took off he checked his oil without starting the bike and didn't see any oil on the dipstick. I told him to start it up and then check it, but he added about 3 funnel's worth of oil to the bike anyway. When we got it to the track it wouldn't start. We tried to bump start it and it putts while it's being pulled, but as soon as he comes to a stop it dies (yes the gas is on). Turned up the idle a bit, but still dies. Choke on, choke off, hot start on...still dies. So I figured it was the carb cause he let the bike sit for a month. He took the jets out of the carb and cleaned them out and drained some of the oil, but the bike still won't start. Changed the plug, still won't start. Any suggestions?

Is there any really bad effects to the bike by over adding that much oil? I thought I read somewhere a long time ago that adding too much oil does something to some rings or something? We're going to take the carb off and clean the whole thing, and change the oil and see what happens.

[250Thumpher]

If you let the bike sit around, the oil drains into the motor. So you won't get a reading on the dipstick.

Oil should be checked ONLY after started, warmed up, and then after it has been sitting off for about 5 mins. If not, it is inaccurate.

It's just been sitting aorund too long. Pull out the plug, dry it off, kick it over without the plug to get some air in there to dissipate the gas, and put the plug back in. Change the oil and add the right ammount (it should be changed if the bike is sitting around)

[oldnbold]

put a new spark plug in it and watch it fire right up.

[3dmxr]

put a new spark plug in it and watch it fire right up.

That was one of the first things I tried. Didn't work. I'm changing the oil in it this weekend. I'll try to crank it with the plug out to get some air in the fuel and see if that works. If that doesn't work my friend's coming up the following weekend to take the carb apart and clean the whole thing.

Anyone ever hear about screwing up the rings by adding too much oil? Or any other suggestions?

[iamsavi]

was the fuel drained out of the carb before it got left alone for the amount of time?...give your (your friends) carb a little clean out, my '02 after sitting around for awhile and after forgetting to drain fuel out of carb gets a little hard to fire up. when a bike dont start just check the combustion triangle or whatever its called, spark, fuel, air

[buzzcutter1]

Try cleaning jets. I had same problem.

[250Thumpher]

was the fuel drained out of the carb before it got left alone for the amount of time?...give your (your friends) carb a little clean out, my '02 after sitting around for awhile and after forgetting to drain fuel out of carb gets a little hard to fire up. when a bike dont start just check the combustion triangle or whatever its called, spark, fuel, air

It's actually the fire triangle, heat, fuel and oxygen. The Tetrehedron adds in a Chemical Chain Reaction. A spark is added in to create fire. To put it out, take out and one of the sides...

Regardless to what you do to get this bike running, you must change the oil before trying to start it if the bike has been sitting for a long time.

[3dmxr]

Changed the oil, put another new plug in, made sure it was getting spark, and still wouldn't start. So it was getting air, and spark, but what about fuel? Found part of the problem. No fuel was getting into the float bowl. The float valve was pretty much superglued shut. After dislodging it, I tried starting it and just got a few backfires. Still, it's some progress. My friend's coming up to completely disassemble and clean the carb. Should start.

[samccomber]

Provided that the bike has a brand new spark plug in it, the first thing I would do is clean the carb, specifically the pilot jet and choke jet, as those jets control the fuel whe you're trying to start the bike. Make sure you change the gas - get some fresh stuff in the bike. A YZ250F with a clean carb and a good plug will absolutely despise starting on old gas. If that doesn't do it, check the compression. Since it's an '01, it should have a manual decompression, so just check the compression by rolling the engine over slowly. If it is difficult to roll it over the compression stroke, your compression is probably OK. However, you said you were able to roll start the bike, which should be extremely difficult if the bike has good compression, especially if you don't use the decompression lever. As far as too much oil goes: too much oil has never killed a set of rings, however too little has. Usually a bike with too much oilin it will start coughing the oil out the crankcase breather (the big hose that comes out the top of the valve cover on your bike). Hope this helps!

[chevymx78]

Changed the oil, put another new plug in, made sure it was getting spark, and still wouldn't start. So it was getting air, and spark, but what about fuel? Found part of the problem. No fuel was getting into the float bowl. The float valve was pretty much superglued shut. After dislodging it, I tried starting it and just got a few backfires. Still, it's some progress. My friend's coming up to completely disassemble and clean the carb. Should start.

you got the ethanol in the gas!!! ive had it a couple times now too...just pull off the float bowl and floats...blow air thru and clean up the white gelled up stuff all of the place and go try again...mines done it atleast twice now...i was told running a fuel treatment to prevent gelling helps out...i dno i keep forgetting to put it in the bike lol

[250Thumpher]

you got the ethanol in the gas!!! ive had it a couple times now too...just pull off the float bowl and floats...blow air thru and clean up the white gelled up stuff all of the place and go try again...mines done it atleast twice now...i was told running a fuel treatment to prevent gelling helps out...i dno i keep forgetting to put it in the bike lol

Gelling happens to diesel fuel...

[3dmxr]

Ok, so he took the carb apart, and cleaned everything out with carb cleaner. Also took the float valve out again and cleaned it again. Bike still wouldn't start. We tryed bump starting it and it started right up, idled fine, and he rode it around for a bit. Rode great. Pulled it into the garage, shut it off and coolant started over flowing and gas was trickling out of the overflow line. Float valve probably got stuck open. Took the carb apart again to clean out the float valve again. Tried to start it again and no go.

The bike has never overheated like that. Even when he's let it idle for 5 min. Would a constant flow of gas into the float bowl cause it to over heat? He's pretty much fed up with it so I'm taking it into the shop for him tomorrow.

[gibbo12]

Save his money and turn the Vaccum Release Plate the right way up [pointed end to top].

[3dmxr]

Save his money and turn the Vaccum Release Plate the right way up [pointed end to top].

It is. Thanks though.