Transmission oil smells and has gas mixed into it, why?

[noid]

So I changed the oil on the blaster, rode it for ~4-5 hours, and I opened the transmission oil fill plug and I can smell a very strong oder of gasoline; after draining the oil, it is clear that gas has mixed with the oil. It doesn't seem to be smoking abnormally or anything like that.

What could cause this? Solutions?

 

[piezzi]

Perhaps your rings are worn out. How's your compression?

 

[Antec1200X]

crank seal gone

 

[sicivicdude]

You need to do a leak-down check. It's possible that you have a leak between the case halves that isn't burning transmission fluid (hence the no abnormal smoke) but is allowing gasoline to be injected into the transmission fluid.

 

[noid]

Perhaps your rings are worn out. How's your compression?

Compression is is just about 122psi.

crank seal gone

From what im reading it could be the right crank seal, but the more i read the more i hear the opposite happening, that the oil is getting burned. Mine isnt getting burned, it is getting gas mixed into it somehow. Doesnt seem to be smoking abnormally.

You need to do a leak-down check. It's possible that you have a leak between the case halves that isn't burning transmission fluid (hence the no abnormal smoke) but is allowing gasoline to be injected into the transmission fluid.

I have a compression tester, and plan to pick up a leakdown tester in the future.

 

[Blaner]

most likely your crank seals but can also be a case leak, i had that once. it may also be your rings, but they would have to be very much tickets for it to be that bad from rings!

 

[noid]

Would only the right side seal (clutch side) cause this to happen, or could the other side be a culprit also?

Number 16 here right?

http://www.yamahapartshouse.com/?gc...IN_VEHICLE)/CRANKSHAFT_PISTON_(YFS200M_-_2000)

 

[yamaboy]

if it was the crank seal on the stator side it would most likely start sucking air and idle realy high. if it was the crank seal on the clutch side it would burn your trans fluid and smoke like a train. when you where riding did it seem to run ok? is there any gas leaking out of the carb over flow tubes?

 

[noid]

It runs pretty well, I just bought it (my second blaster); so it must have happened while the previous owner owned it. I dont recall seeing gas coming out of the overflow tubes (havent really looked closely) however i did notice a smell of gas sometime when i had my face near the engine yesterday. Why? does the carb dump excess gas in the trans?

 

[yamaboy]

the carb doesnt dump excess fuel in the trans. if the float needle in your carb is stuck open it could be over filling your carb and leaking into your trans thought your cylider. does your air box have any fuel in it?

 

[sicivicdude]

The other side (stator side) does not connect to the transmission.

The right side crank seal USUALLY involves burning transmission fluid. A leak down test would confirm if you are actually having fuel pouring into the transmission fluid.

Part number 16 for the crankcase is the transmission vent

 

[noid]

Ill have to check on the airbox, but what I have noticed is that it is using an awful lot of gas in the short ~2 hour ride i did last weekend. I ride a TRX450R, this blaster is my girlfriends, I outgrew and sold my old blaster. It seems to idle fine however, if the needle was stuck open wouldnt the idle be out of wack?

Another thing i noticed is on start up from bone cold, it will put-put-put-put-put when idling, however the idle will stay constant. After it warms up idle is nice and constant. After its somewhat warm, putting the choke on will kill it.

Furthermore there has been a couple occasions where i reved the engine, and the idle stayed high and wouldnt come down, when i put it in to gear, or pulled the chock a bit, it would go back to idling normally.

 

[sicivicdude]

the carb doesnt dump excess fuel in the trans. if the float needle in your carb is stuck open it could be over filling your carb and leaking into your trans thought your cylider. does your air box have any fuel in it?

The transmission and crankcase area do not connect. A flooding carburetor cannot fill the transmission fluid unless there is a break between the case sealing surfaces.

 

[sicivicdude]

Idling high until the choke is pulled out is a sign that the engine is sucking in air not through the carburetor...

 

[noid]

pulling the choke to calm it down, but then i push the choke back off, and it stays nice and low.

I know for sure gas is getting into the transmission it has a very strong oder, it has made the oil thinned, and the oil is a greeny color.

 

[sicivicdude]

I will say it again, you have a leak between the crankcase area and the transmission but above the normal transmission fluid level.

You need to perform a leak-down test and confirm. You will probably end up pulling the crankcase apart to find the problem.

 

[noid]

A normal car leakdown tester wont work right? From what i understand there are 2-stroke specific ones.

On a sidenote I wonder if the gasoline acts as a cleaning agent at the same time. I know some people use gasoline to clean stuff all the time.

 

[N8tsNastyBlasty]

make sure the over flow or vent lines on the carb arent connected to the tranny vent. sounds crazy but ive seen dumber zhit. or maybe the previous owner took the whole oil and gass mix idea out of context. lol

 

[Chance]

Where can I get a full case gasket i can find any on ebay

 

[Larry's Shee]

Where can I get a full case gasket i can find any on ebay

No such thing as a full case gasket on a Blaster. The two case halves use Yammabond or 3Bond between case