Lower unit drain plug

[captchuck]

OK guys, all my little engines are ‘vintage’ but my daily runner during fishing season is a 1988 Force 125 mounted to a 1988 Bayliner Trophy. The problem I am having is removing the drain screw for the lower unit. It is an allen plug and will not move to the extent the wrench will not hold as the hole is rounded. I know the ‘approved’ method of repair is to drill it out and retap. My question is has anyone done this and from THEIR EXPERIENCE what size drill and tap was used. I can make an intelligent guess, just curious if anyone has done it and won the battle.

[chris-p]

Have a welder tack on a socket or the like then turn it out. Drilling and retapping can be a nightmare. Sometimes goes well, but I have found welding something onto the plug, then turning it out is MUCH easier.

[punchbug]

A different option is to use a left hand drill. You can get them at any industrial supply store. Pick a size that is slightly bigger then the rounded hole. The torque will usually break the screw loose before you drill through it. Of course you will need to buy a new plug when you are done.

[jerry-ahrens]

I’ts been a long time since I saw one of those, but I remember them. Sometimes a new allen wrench will help, because a used one will often times have wear on the corners causing it to slip. Maybe even try a metric size, as it may tap in with a small hammer.Otherwise you could probably drill it in the center, then use a square fluted style extractor. They work much better than the spiral easy outs. The good news is, that it’s probably not in that tight.
If it were me, I would avoid having to tap new threads… try to extract the drain plug and save the threads.

[garry-in-michigan]

The heat of the welding will expand the bolt, making it easier to turn after it cools. This was a favorite when I worked at a FORD factory. No welder? Clean out the socket with solvent on a "Q"tip and put in a dab of your choice of steel filled epoxy putty immediately forcing in a new proper size Allen wrench. after it hardens it should unscrew. cut off the Allen wrench and throw away the plug. . . 😉

[billw]

If you have a set of Torx bits, find the closest size and pound it into the rounded out Allen hole. Unscrew the plug and pound it off the bit. Then, of course, get a new plug. Works every time.

Long live American manufacturing!

[jeff-register]

Way to go Garry!! Save all you can 🙂

[jerry-ahrens]

quote BillW:

If you have a set of Torx bits, find the closest size and pound it into the rounded out Allen hole. Unscrew the plug and pound it off the bit. Then, of course, get a new plug. Works every time.

That sounds like a great idea. Never tried that

[crosbyman]

my last one on the 75 ETEC was a pain, it came out by chiselling …

I used an old wood chisel and knocked into the edge of the plug counter clockwise moving the chisel to a new spot it finally came out

no more allen heads for me … slotted plugs only !

Joining AOMCI has priviledges 🙂

[jeff-register]

Jerry,
I find Snap On allens are more presise & manufactures sloppy,

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