Engine Holder Steel Plug Corrosion

[tunagoose]

I recently purchased a 2001 DF90 4Stroke (approx 370 hrs) and learned of the corrosion issues associated with the steel plug Suzuki elected to use (instead of aluminum). I am trying to be proactive in addressing this design flaw and would appreciate any feedback anyone has to offer. I am particualrly interested in the success others have had in replacing the steel plug/welding option vs. replacing the entire engine holder.
Thanks-
Tunagoose

[nelbur]

You can replace the steel plug with an aluminum one, although removing the steel plug can be very difficult. Search the forum for the many posts on this subject. I had to drill out my steel plug so the portion remaining in the threads could be unscrewed.

[tunagoose]

As far as you know, has replacement with an aluminum plug been a lasting fix?
thanks for reply-

[seacat47]

I have 2001 Df 115s on catamaran , after recently becoming aware of engine holder problem , I decided to replace steel plugs with aluminium plugs. My steel plugs came out fine and put new plugs in ,but during the process i guess some of the corrosion broke loose and had a small hole developed on the bottom of threads where plug screws in. After looking at cost of new engine holder 700.00 plus all the labor involved I elected to have mine welded. I took it to a local aluminium welder had the side covers and wires out of the way so all he had to do was grind corroded area out and weld hole up. He charged me 25.00 . I talked to several people that had this same fix and had sucess with it.

[tunagoose]

Good to know others have had success with aluminum plug/welding option. I was only aware of 1 steel plug in the engine holder known to be a problem...you referenced plug(s). Where were the additonal plugs located?
Feedback much appreciated -

[seacat47]

sorry when I referred to replacing plugs ,I have twin DF115 on a catamaran, I was referring to one on each engine.

[tunagoose]

Please view this repair

I removed the mid section cover and discovered that an effort to repair the plug was already done by the 1st owner (I am 3rd owner, 2nd owner had no knowledge of issue).

The repair APPEARS to have included a combination of an aluminum plug and JB WELD.

Please let me know if you agree with this assessment and any thoughts you have from appearance of repair.

Considering that replacing the steel plug with an aluminum was a viable option for the 1st owner, is it reasonable to think that the "external" corrosion was minimal ?

Are there any options for evaluating internal corrosion at this point ?

ANY FEEDBACK IS MUCH APPRECIATED

[nelbur]

I removed the mid section cover and discovered that an effort to repair the plug was already done by the 1st owner (I am 3rd owner, 2nd owner had no knowledge of issue).

The repair APPEARS to have included a combination of an aluminum plug and JB WELD.

Please let me know if you agree with this assessment and any thoughts you have from appearance of repair.

Considering that replacing the steel plug with an aluminum was a viable option for the 1st owner, is it reasonable to think that the "external" corrosion was minimal ?

Are there any options for evaluating internal corrosion at this point ?

ANY FEEDBACK IS MUCH APPRECIATED

I can't be sure what you have there. It looks like you may have the steel plug still there with some JB Weld around the plug, but I am not sure. See if the plug is attracted to a magnet. Typically the exterior does not corrode. The aluminum housing corrodes from the inside and perforates near the plug letting exhaust escape which gets sucked into the engine intake. If the JB Weld is patching corrosion holes you would likely want to remove the plug and weld an aluminum plate in it's place once you removed any thin portions of the housing.

[noelm007]

Never heard of a "patch" job being permanent yet, only true fix, remove and replace, weld hole, or new engine holder, everything else is just buying time, I kind of think that "repair" looks recent, my guess is the previous owner knew about this, and patched it up to sell, but I could be wrong?

[seacat47]

appears your assessment of new plug with JB weld is correct. In my opinion if external corrosion was minimal there would have not been a need for JB weld just a new plug should have sealed it. From my research on this, this would be a temporary fix, the only true fixes are either welding hole or replacing engine holder.

[tunagoose]

Thanks to all for input...any other issues to be aware of with this series of motor (2001 DF90) ?

Good motors?

THANKS

[seacat47]

As stated eariler I have twin 2001DF 115 which is basically the same engine as DF 90 . Other than engine holder corrosion they have been flawless, I bought them new and they now have over 1900 hours and still run great. I plan on running them a few more years

[tunagoose]

Going with the welding option. Any steps to follow or words of wisdom?
Is it necessary to pull/flush lower unit should any metal shavings get in exhaust cavity?
Thanks!

[seacat47]

I pulled lower unit and flushed out exhaust cavity .

[tunagoose]

I was recently told that TIG welding is best option for this repair ....but have never seen any reference to TIG welding in all my reading on the corrosion issue. Anyone know if TIG welding has been used in any/all of weld repairs that have been done?