4 stroke making oil or something else wrong?

[basstender10.6]

My 1999 evinrude 5hp 4 stroke runs great but after running for a while at high rmps, it will loose power begin to smoke and puke oil down the leg from the midsection. I have been told that it is most likely the engine "making oil" and when the level gets too high it pukes the excess oil into the intake through the crankcase vent hose, which causes smoking and what doesn't get sucked in goes into the lower pan, then drains all over the leg. Could this be the problem? If so, apparently I have to change the oil more often and make sure to keep it on the lower side. Or could something else be wrong?
Thanks for the help in advance.

 

[raczekp1]

Re: 4 stroke making oil or something else wrong?

watwe s mixing with oil brcouse bad head gasket

 

[basstender10.6]

Re: 4 stroke making oil or something else wrong?

Water mixing with oil because of a bad head gasket?

 

[boobie]

Re: 4 stroke making oil or something else wrong?

Could be a bad head gasket or it's running to cold. Usually runnig cold makes oil.

 

[Silvertip]

Re: 4 stroke making oil or something else wrong?

You've given us some information but it is not of much use. Have you ever checked the dip stick to see what the oil level really is? Have you changed the oil and filter to see if the problem repeats? Did this just occur? Is the motor new to you or have you owned it for awhile? We need details. But some of the things that can happen are a ruptured fuel pump diaphram that allows raw fuel into the intake all of which cannot be burned. If the oil looks like a milk shake, you probably have a head gasket or cooling system leak that is dumping water into the oil. Continue to run it that way and your engine will quickly turn into an expensive anchor. Do some checking and let us know what you find.

 

[basstender10.6]

Re: 4 stroke making oil or something else wrong?

I puchased the motor used last May and it ran great. But the first weekend I took it out, problems started. It was running fine until I ran WOT for a few minutes. The motor lost power and began smoking out of the exhaust port (the above water port). Then oil started leaking fro the mid section (somewhat milky). I added more oil after it finished leaking and the problem kept on happening (Total of about 4 times over the summer June-Early Sept). I thought it might be a bad head gasket, but I didn't totally understand how that could cause oil leaking. Maybe after running WOT for a while the engine got warmer and as the head expanded from the heat the oil seeped out. The odd thing is that after the oil would be finished leaking out (usually after night) the motor started up and ran fine.
Thanks for the help!

 

[raczekp1]

Re: 4 stroke making oil or something else wrong?

i would look at oil colour first,
secend step is to check compresion when cold, and warm up motor and try compresion
look at termostat also
if problem is not in bad head gasket(compresion tests will prove this) so secend is bad oil ring at piston.
oil ring is to seal and keep oil down at conecting rod

 

[daselbee]

Re: 4 stroke making oil or something else wrong?

Broken fuel pump diaphragm leaks gas into the oil. Does the oil smell like gas?
Is your model number E5R4EEM?

 

[basstender10.6]

Re: 4 stroke making oil or something else wrong?

Broken fuel pump diaphragm leaks gas into the oil. Does the oil smell like gas?
Is your model number E5R4EEM?

Yes, that is my model number. I changed the oil before I stored it for winter so I can not tell if it smells like gas. How would I know if the fuel pump diaphragm is broken?

 

[daselbee]

Re: 4 stroke making oil or something else wrong?

Well, pump the primer bulb. If it never gets hard, it is possible that the fuel is shooting into the crankcase.
Also, if the oil smells like gas.

If you had water going into the crankcase, you would be looking at grey mayonaisse when you changed the oil or checked the level.

Your fuel pump is on the back of the engine, mounted to the cylinder head cover????? Round thing....????
Fuel lines going to it? I hope I have your engine pictured right in my mind.

 

[basstender10.6]

Re: 4 stroke making oil or something else wrong?

Well, pump the primer bulb. If it never gets hard, it is possible that the fuel is shooting into the crankcase.
Also, if the oil smells like gas.

If you had water going into the crankcase, you would be looking at grey mayonaisse when you changed the oil or checked the level.

Your fuel pump is on the back of the engine, mounted to the cylinder head cover????? Round thing....????
Fuel lines going to it? I hope I have your engine pictured right in my mind.

Yes that is exactly correct. I checked out the fuel pump today looks good. I looked inside with a flashlight and everything in the cylinder head cover looks clean (actually it looks brand new). I am beginning to take apart the power head to check the head gasket. If the head gasket is fine, I am starting to believe that it might be the rings.