2005 mercury 60/40 2 stroke factory jet leaking oil like crazy

[Berex]

I have a 2005 2 stoke 60/40 jet starting about 10 months ago it started leaking fresh oil out the exhaust.i pulled the plugs and found the bottom cylinder to be full of oil. This is not just a couple of drops it's a puddle. I tried replacing the check valve part #22-818994 which someone said was the problem pretty much out of ideas. Thanks in advance

 

[racerone]

Serial # of the motor ?

 

[Berex]

OT981902

 

[sutor623]

I been running these jets for years!! Love 'em. I have owned 3 60/40 jets, a '94, '99 and an '07 (4 stroke) which I love.

Do you still have the oil injection hooked up? Im guessing you do if you replaced the check valve. That would have been my guess also.

Sounds like you are getting oil into the bottom cylinder from your oil tank. Got to be an issue there. You can try temporarily unhooking your oil alarm and plugging your oil injector pump's 2 barbs, pre-mix your gas 50-1 and see what happens.

Also, I know this sounds dumb but make sure that check valve went in the proper direction.

 

[sutor623]

I also have had that oil pump work its way loose on my block and had oil leaking into the cowling. Maybe check to see if your pump is still tight on the block. (Very hard to get to if they need tightening.)

 

[Berex]

Yes still have the oil injection hooked up i may end up bypassing it if I can't get this figured out seems like it's just gravity feeding oil if the check valve was backwards it seems like it wouldn't feed at all guess I could have gotten really unlucky and got a bad check valve

 

[sutor623]

Well, Im not sure if the injector pump could be leaking internally, allowing oil to bypass it, but that surely sounds like a possibility. I have never taken one apart before, though.

Are you smoking like heck while running? My guess is that the oil is entering the crankcase down in cylinder 3 and getting drawn into the combustion chamber while running.

You can also blow through your old check valve, I believe if you blow through it you will only get air flow in one direction.

I have also seen the tank pressurize itself on hot days and force oil down past the check valve.

Another thing you could do is pull the oil hose off of the injector pump and put it in a bottle and see (while the check valve is installed) if the oil self drains into the bottle.

 

[sutor623]

Not sure this will help but here ya go:
http://www.boatinfo.no/lib/mercury/manuals/45jet-50-55-60.html#/126

 

[Berex]

Thanks so much for the info I'll try a few things my first thought was the tank pressurizing because it started in the summer but it's still doing it and it has been cold. The funny thing is it runs great no smoke expect startup so it seems injector pump is fine but I'll look into it.

 

[sutor623]

That oil pump has 2 o-rings where the oil pump mounts to the block. I think all that they do is protect cylinder 3 crankcase compression but it may be worth a look. How do you store the engine? Being a jet I would imagine it just stays tucked in all the time.

Have you ever had the carbs off and taken a look at the reed valves? Does the motor start easily and run well at all ranges?

 

[Berex]

Never had the carbs off I store it down in the running position in the garage I took it out a little while ago and it fired right up and ran well after I drained the oil out of bottom cylinder

 

[Berex]

I should also explain that initially the oil smelled like gas so I thought maybe the gas tank was pressurized and in turn pulled oil with it but when I unplugged the fuel line I still get oil but no gas with it which is what really led me to believe it was just gravity feeding from the oil tank

 

[sutor623]

I would put a small hose on the outlet side of the injector pump, fill it with oil and put the other
Side of the hose on the inlet of the pump and then take the T out of the fuel line. Then see what happens