Exhaust question

[MBJJ2369]

I looked at a 1991 48 SPL today. The motor fired right up, idled good, had good flow of water from the pee tube (ran on muffs). We ran the motor in forward and reverse and let it idle for about ten minutes. Turned it off and it cranked right back up. A few minutes later i notice a thick gray goop running down the skeg. It was on both sides on the skeg coming from the area where the prop and housing meet. Does this mean there is a problem? The owner said he was told by his mechanic Johnson's do that and it was nothing more than exhaust. I did not pull the plug from the lower unit and check the oil there to see if water was mixing with oil.

Any suggestions or comments??

 

[Lightwin 3]

Not an issue but could probably use a good "decarb". Search this site for decarb process.

 

[flyingscott]

Normal a decarb is not going to fix that. I would make sure the lower unit is in good condition before you purchase. They are not known as robust units.

 

[MBJJ2369]

The motor is on a pontoon boat. The owner said he bought the pontoon because he wants to make a floating deck and doesn't need the motor. He said he has only cranked it up and let it run 2 or 3 times for a few minutes. He said he isn't sure how often the guy he bought it from ran the boat.

 

[WhiteRice]

Could've been fogging oil too. If the owner was smart and knew it wasn't going to be running for a while he may have fogged it. First few times it runs the fogging oil with come out of the exhaust and a greyish black goop.

 

[MBJJ2369]

This is the same boat that I asked about earlier. The tilt assist does not work. He thinks either a broken cable or lever. He is asking $1000 for the motor and controls. What do y'all think?

 

[F_R]

I wouldn't comment on the price, but I will say that goop coming out the exhaust is totally normal. Especially if prolonged or repeatedly running it out of the water (on muffs) where it is not flushed away. Where do you think the oil that you put in the gas goes?

 

[MBJJ2369]

I can understand the oil from the gas needs to go somewhere, but the amount of grayish goop coming out seemed to be alot. It was the color of the stuff coming out that also concerned me.

 

[F_R]

The oil goes through the engine where some of it is burned (smoke) and the rest goes out the exhaust where it is emulsified with warm water that has done it's job, and picks up carbon particles from the exhaust housing. Then exhaust flow and gravity takes it out the bottom.

Running at idle on muffs accentuates the mess because it doesn't get hot enough to burn much of it. Run it in the real world, on a boat, on the lake, and it will be much cleaner.

 

[boobie]

I believe I told you in that other post what the tilt assist is worth. It's you call.

 

[WhiteRice]

In the end, it's your purchase and we have no financial interest in it at all.

It also looks like you have gotten a LOT of good advice and are chosing to ignore it.

Happy Boating...