1999 250 EFI excessive smoking

[balistikb]

Hello all, first let me say this is my first post.
I have a 1999 250 EFI that smokes allot.
When first starting my engine it smokes allot whether it has been sitting for a few days or sitting for five minutes.
It smokes a hell of allot when I give it throttle as well as smokes when I am just sitting at the dock.
I would like to try and troubleshoot this myself so I am looking for guidance as to where to start.
Any help that I can receive will be greatly appreciated.

 

[balistikb]

Re: 1999 250 EFI excessive smoking

Any ideas?

 

[hkeiner]

Re: 1999 250 EFI excessive smoking

Unscrew the cap on the remote oil tank five minutes after you shut off the motor. If you can hear air pressure escaping from the oil tank, then perhaps the crank case pressure check valve is defective. If this check valve does not relieve air pressure from the remote oil tank in a timely manner after shut down, excess oil can be pushed into the fuel line after shutdown causing excess smoke when the motor is next started. This is a common problem on older carbed motors with oil injection. I am not positive that this also applies to EFI motors, but this quick troubleshooting test is worth a try until you get better informed responses to your post. Good luck...

 

[balistikb]

Re: 1999 250 EFI excessive smoking

If you are referring to the oil tank on the motor, I cannot open that after I shut down the motor. I have to wait a while and then after much force it opens.
Is that a problem?
Thanks for your reply hkeiner.

 

[hkeiner]

Re: 1999 250 EFI excessive smoking

If you are referring to the oil tank on the motor, I cannot open that after I shut down the motor. I have to wait a while and then after much force it opens.
Is that a problem?
Thanks for your reply hkeiner.

The remote oil tank is located somewhere inside the boat. It holds about two gallons of oil and you put oil in it after the oil gets used up by the motor. The cap can be easily unscrewed from the remote oil tank when the motor is turned off. The other oil tank under the cowel is the reservoir oil tank and you should not unscrew the cap on this tank.

 

[balistikb]

Re: 1999 250 EFI excessive smoking

Ok great I will check that. Is the only way to test is to replace that?
Also i read that Synthetic Oil will help reduce the amount of smoke. Do you find that to be true?

 

[balistikb]

Re: 1999 250 EFI excessive smoking

Well I am back. I am still having allot of smoking from the outboard. It smokes allot after shutdown.
I have replaced the check valve and aligned the oil pump acording to the book. Any other ideas?

 

[hkeiner]

Re: 1999 250 EFI excessive smoking

So that there is no mistake, confirm which check valve you replaced to make sure you replaced the correct one. There are three check valves on the oil injection system, and the crankcase check valve is the one that can cause excessive smoke at start up if defective.

Also, to be sure I understand your symptoms correctly, you say that the motor only smokes right after start up and that the motor no longer smokes excessively at idle after it has been running for a short while. Is that right?

 

[balistikb]

Re: 1999 250 EFI excessive smoking

If I am looking at the outboard from the back. I replaced the checkvalve on the bottom right towards the front of the motor.

 

[hkeiner]

Re: 1999 250 EFI excessive smoking

There are two check valves on the right side of the motor. The crankcase check valve screws directly into the crankcase body. The other check valve on the right side is located in-line on the oil line going to the reserve tank.

Assuming that you replaced the correct check valve, that you adjusted the oil pump correctly, and that your other link and sync settings are all OK, then I can only suggest the following unlikely but possible causes due to a parts failure. These are:

1) A 2 psi check valve located in-line beween the oil pump and the fuel pump. If this valve is stuck open, then oil could siphon into the fuel line when the motor is off and cause excessive smoke at startup.

2) A thermal air valve located at the rear of the motor with an air hose that runs from this valve to the carbs. This valve controls air flow to the low speed air jets in the carbs. The valve should be closed when the motor is cold and opens when the motor is warmed up. If it stays closed too long, it would cause the motor to run rich at idle and smoke.

Both of these parts are not the most likely causes for excessive smoke at startup, but they are easy to replace and not expensive. Other than the above, I have no other ideas unless your carb floats are poorly adjusted and you are just getting a bunch of smoke due to flooding.

Good luck...

 

[balistikb]

Re: 1999 250 EFI excessive smoking

Ok after looking at the service manual I see that I changed the Crankcase Pressure One Way check valve.
I only see one more which is a 4 PSI Check valve.

 

[hkeiner]

Re: 1999 250 EFI excessive smoking

Well, I was thinking about a carbed motor and not EFI. While there are some common parts to the oil injection systems (such as the crankcase check valve), the EFI does not have the other check valve or thermal air valve I was discussing in my last post. At this point, I have run out of advice specific to the EFI motor oil injection design.

 

[balistikb]

Re: 1999 250 EFI excessive smoking

Still thank you for your time.