Corroded O2 Plug Removal

[ezrollin]

After read a heads-up on on Suzuki's corroding problem with the O2 plug which is located on the port side of the engine holder I checked mine and sure enough it is corroding. I have been applying WD-40 to help loosen it up for removal,the hex hole is to far gone to use a hex wrench so I will have to use a screw extractor etc. and maybe a little heat.Anyone successful in removing this plug or any tips other than what I have stated ?

[seacat47]

Just removed mine with hex wrench but it had corroded thur at the bottom of threads it would have eventually given trouble. I had the threads ground off to good metal and welded the whole totally up . In my case it was weld it or replace engine holder which is expensive for parts and labor

[jHydroman]

I was successful by using KROLL (penetrating oil) and a combination of heat and cold. I used an electric heat gun after soaking overnight with Kroll and then sprayed around plug with quick freeze( spray can) I repeated this procress several times over a period of several days. Gave the plug hard blow with hammer and chisel,(in loosen direction) this worked on both engines, no thread damage on either engine holder. Installed new SS plugs.

[ezrollin]

Thanks guys, I,m not looking forward to this but it has to be done. Unfortunately mine has already got to the point where the hex drive hole is to far gone but I can tap a small chisel into it.I took an outboard repair course many years ago and the main thing the instructor stressed was never force anything,if it doesn't come loose apply more blaster,heat,tapping etc. the biggest mistake diy make is breaking of bolts in the motor.

[noelm007]

Just be careful "tapping" around that area, if there is some corrosion started, it will be quite thin, I have seen a few use a small drill and drill the very edge of the plug near the thread in a few places to loosen it up a bit, or drill a series of small holes right across the plug to allow it to be bent out of shape with very little force, breaking it away from the thread.

[ezrollin]

Just be careful "tapping" around that area, if there is some corrosion started, it will be quite thin, I have seen a few use a small drill and drill the very edge of the plug near the thread in a few places to loosen it up a bit, or drill a series of small holes right across the plug to allow it to be bent out of shape with very little force, breaking it away from the thread.

Yeah, I plan on a lot of penetrant over a period of time,some mild heating and cooling,if that doesn't work then like you said, drill it until it can be bent out.If the thread are shot I'll weld a plug .

[jHydroman]

One good thing the hex even if stripped pretty much provides a center for dirlling, might want to try drilling with a left hand twist drill, I have had some luck if the drill gets in a bind and grabs the material you are trying to remove.

Good Luck.

[nelbur]

I drilled out the plug using a 1/2" bit. As said, the hex keeps the bit centered. I then put a saber saw metal bit in a locking plier and sawed three slots toward the thread, stopping just before I got to the thread. I then unscrewed it using a hammer and chisel. I actually finished using a hammer and a large nail set as the chisel was just cutting the head off the plug.

The replacement plug should be aluminum, not stainless steel. You want to get away from the dissimilar metals.

[artdf175]

I am not sure what size the allen head is..
however.. you can get at Home Depot or maybe an autoparts store an ez-out attachment for you drill..
it has one one end the reverse drill bit to make the hole the correct size (sometimes this catches enough to back out screw.. ) for the tapered bit on the other end.. I have used this a number of times for very stubborn situations where a screw head has been destroyed trying to remove same..
art