Why aren't we warning about steel plug?

[briscoe]

I have a 07 DF140 with a around 200 hrs on it, fish only salt water. I flush the engine with Salt Terminator after every use. I found water in my oil this last trip and began to query issues with "water in oil".
Holy cow, there is a terror out there that is destroying our engines at the engine holder and no one is telling us. There is a steel plug, which is corroding on the inside since it is dissimilar metal with the aluminum holder. This is where the engine exhaust gas passes. I believe some of that gas is used for engine air and some of it goes out the bottom through the propeller (exhaust). I am not clear on the dynamics, only reading what Egorena has posted with others information, there is risk for erosion of the aluminum holder, which leaks out the hot gases. This has been ongoing for 10 or more years! Oh no....
This morning I worked that plug out very carefully and it is severely ate up on the end of the plug. Using the correct allen wrench and penetrating oil you can work it back and forth and it will come out. The inside of the holder still looks ok.
The question now is what to do about it? They are apparently making the newer engine holders without this plug (casting over that spot), as it serves no purpose. To see the plug I'm talking about click on the purchase suzuki parts link above and look up engine holder under your model (the plug is on the left, port side).
I am disturbed by this information!!! For now, I flushed the engine when I found the emulsified oil and don't know what to do about the plug? Help.... Houston, we have a problem....

[briscoe]

It looks like exhaust gas erosion!

Looking at this plug again, it appears to be erosion from the hot gases. The way the plug appears to be sticking in so far into the housing and the hot exhaust flying past it is wearing down the plug.

Pics aren't very good, but this is not corrosion, it is erosion!

[boats.net]

You can change the plug, there are no superceeded plugs that are more resistant.

[briscoe]

Check engine anodes (internal)

In all fairness, I searched this issue on WWW. One of the culprits may be the internal engine anodes. If you own the manual it is not a recommended maintenance item. On my engine there are four on the port side. Two at the head (single bolt removes cover) and two in the middle of the motor, near the electrical fuse cover. The middle two are directly above the fresh water flush plug. Mine, at middle, were completely covered in a wax-like substance and I am certain they were not working. The two near the head were ok. So I believe the corrosion issue people are having may be from used up anodes.

[nelbur]

Briscoe, is your plug on your '07 steel for sure. The plug was redesigned in the '05 model but there is no mention of the material it is made from in my manual. If a magnet sticks to it it is steel. I have a '05 and if it is steel I will have an aluminum one machined. My boat is on a lift or I would remove the side covers and check mine. Another project for this winter.

The wax like substance you found on your anodes sounds like what forms on zinc in brackish water. Suzuki sells aluminum anodes for brackish water which do not have this problem. Another of my winter projects.

[briscoe]

Yes it stuck to a magnet. I think the hot exhaust is a separate issue from the corrosion caused on the aluminum engine holder that contacts the water. When I bore scoped my engine holder it looked good, but anodes were definitely needing attention. I wonder if issues with corrosion are one thing and holes at the plug another? Just my observation.

[briscoe]

oww my df140 is in trouble

Well, I took my boat to dealer, had extended warranty. Suzuki told them it was probably the oil cooler. NOT! They pulled the power head today to explore further. No word back.
This is an 07 with 300 hours. I'm bleeding out. If it's the engine holder, corrosion is not covered. Yes I had anodes and yes they don't help the holder mounted so high on the engine. This all makes me tired. I thought my Suzuki was going to be a better engine!