2 cycle oil in primer bulb

[Tomstevensone]

Hello, My last time on the water last year my 2003 Merc xr6 would not start. It does have oil injection and is carbureted. I finally got around to messing with it today. I replaced the fuel filter and found 2 cycle oil in the fuel filter, I changed the primer bulb and found 2 cycle oil in it also. It certainly won't run on oil only so how is the 2 cycle oil backward flowing? There must be a check valve stuck or something. Any ideas would be greatly appreciated. Thanks in advance

 

[Faztbullet]

Oil tank in boat not bleeding off pressure thru valve on block

 

[racerone]

Agreed oil tank pressure is supposed to bleed off.

 

[Tomstevensone]

Oil tank in boat not bleeding off pressure thru valve on block

Thank you for the help

 

[Tomstevensone]

Oil tank in boat not bleeding off pressure thru valve on block

Thank you for the help

 

[MercGuy]

I have a 1998 115 with oil injection. I installed a clear fuel filter just after the primer bulb and it has always had 2 stroke oil in it after sitting for a day or 2.

I assume that is because the oil pump and mixing with fuel happen at the bottom of the engine. Then there is a fuel line that runs to the top of the engine for the upper carb. When the engine is turned off the premixed fuel/oil simply drains back down the fuel line towards the tank due to gravity.

When I pump the primer I push that premix back up to the top of the engine and all is good.

 

[dingbat]

I have a 1998 115 with oil injection. I installed a clear fuel filter just after the primer bulb and it has always had 2 stroke oil in it after sitting for a day or 2.

I assume that is because the oil pump and mixing with fuel happen at the bottom of the engine. Then there is a fuel line that runs to the top of the engine for the upper carb. When the engine is turned off the premixed fuel/oil simply drains back down the fuel line towards the tank due to gravity.

When I pump the primer I push that premix back up to the top of the engine and all is good.

It shouldn't do that. The fuel system is not vented to atomsphere (under vacuum). You have a leak in your fuel system somewhere.

 

[Tomstevensone]

Thanks for all the replies, They have helped me a lot. I figured it has to be a stuck valve letting mixed fuel flow backwards

 

[racerone]

On a 1998 model 115 HP the oil tank may be vented.-----On the XR6 the oil tank in the boat and crankcase PRESSURE in it keeps oil flowing to the motor , when motor is running.