Best way to remove rotten mild-steel screws

[Joe Myerson]

A previous owner (there have been at least two) replaced the original vent for the head with a miniature clamshell vent. The vent is stainless, but this genius attached it to the transom with some kind of mild steel or worse screws.

I was able to dig out lots of what looks like mud from the vent, using a piece of stainless wire. I suspect those lovely little mud wasps have been using the vent as a winter residence. I'd like to replace this vent with a bronze one (with screen) from Spartan, but I'm not sure what would be the least destructive means of removing the current vent cover.

It also looks like my arms are not long enough for me to squeeze into the starboard corner of the space beneath the after deck. I'm not sure how to post a photo of this vent, other than by attaching this DropBox link.

https://www.dropbox.com/s/q92yfzc8z96yq ... .57.05.jpg

Thanks,
--Joe

[RC James]

If I remember correctly, access to the starboard stern is available by removing the engine panel from the cockpit. It will still take a long, flexible arm (really skinny ARMS if using both) to attack the hose and clamp.
Drilling out the old rotten screws may be the easiest fix, with a little JBWeld or similar to fill the holes.

Mud wasps! Been there. I used a long flexible wire -read 'coat-hanger'- to break up the rest of the mud-crud, and then sucked it all out w/a shopvac.

GoodLuck

RC

[Gary M]

If it were me:

First I would hope these are just sheet metal screws and I'd try to remove them with a small vise grip.

When that didn't work I would try an easy out.

Then I would hope that by pulling off the vent cover the hose and clamp would come with it so I could remove it from the hose.

It not, well good luck.

Gary

[Jim Davis]

Joe

Considering that they are probably crumbling and you don't have much to grab I'm not sure what success vise grips will have but it is a good start. With their small size easy outs probably will be a non starter. One thing to consider is a very small hole saw type bit made for drilling tile and glass. Get one with an inside diameter just a hair larger than the screw and drill it out.

I have also used pieces of stainless tubing for this. Cut a "drill bit" about four inches long and drill it out. Leave the end of the tube ragged (perhaps notch it a bit with a file.

Then fill the hole with JB Weld and drill for your new screws.

The link below is just to start you thinking.

http://www.diamond-drill-bit-and-tool.c ... -Bit.shtml

[Russell]

Really, if they are that rusted and falling apart, I would try to hammer them out first. Take a machine screw (since it will have a flat tip rather then pointy) of the appropriate diameter, place it in the hole where the rusty screw is and give it a good whack.

Ultimately though, you might have to resort to drilling it out. You will probably muck up or enlarge the hole a bit in doing so, but we are not talking below the water line or structural areas here. No need for anything fancy, refill the now oversized hole with epoxy thickened with silica, then redrill for your new SS screws.

[John Stone]

I have had great luck with "grab it" screw extractors. I have remove hundreds of stripped screws and, based on looking at the picture, this looks similar. The "grab it" is a short drill bit with a reverse threaded drill bit on one end and a reverse threaded extractor on the other. You first drill down for about 10 seconds then flip the bit around and the extractor grabs into the edges of your just drilled dimple and out it comes. If there is any decent metal under the rusty head it should work. I have only had it fail me a few times. I have had some stubborn screws break the grab it tip off but considering how many screws I have removed this way I give it pretty high marks.

http://www.lowes.com/pd_299780-41877-84 ... facetInfo=

You can find a video of it on You Tube.

[Joe Myerson]

Thanks for your suggestions, guys.
The first thing I tried was to use Vise-grips on the little b*stards. The heads just crumbled.
The second thing to know is that they, and the clamshell vent, are very small (I should have taped a dime to the transom for comparison).
I did get some flexible wire inside, and lots of dry dirt came out. The shop vac brought out even more dust (dry mud).
John, how small a screw can be pulled with that grabber? It might be worth a try. Otherwise I'll just have to drill away and fill the resulting holes.
We'll see. If the head works, I might wait until the fall to make this switch, since I've already put the engine panel back in place.

Thanks again,

--Joe

[John Stone]

Joe,
The three bit set that was in the link has a pretty small bit. I'd say it should handle as small as a #8. I think for both ends of the bit your drill should be in reverse. Good luck.

[sharkbait]

Everyone should own a set of left-handed drill bits.

[John #126]

Here's another option. They are a worthwhile investment.
http://www.highlandwoodworking.com/set3 ... ctors.aspx

[John Ring]

Did you try popping the heads off with a hammer & cold chisel? Those are pretty small, well rusted soft steel. The heads might just pop off after a few whacks. Then you can push the threaded part through inside.

John