How to remove broken gearcase screw?

[old motor]

On my 1986 Evinrude 9.9 the lower gearcase oil filler screw is now loose, but won't come out. I turned it to change the gearcase oil, and there was a tiny snap, and it now turns around non-stop. I <br />guess either the screw has broken or the case threads have stripped. <br />My immediate problem is how to remove the screw. I can't get a grip on it because it is set flush to the outside of the case. Does anyone have any suggestions?<br /><br />Then, if I can remove the screw, what should I do next? If the case is stripped, can it be rethreaded? I suspect not, since it is cast aluminum, but I'm no expert. Again, any <br />suggestions?<br /><br />Thanks in advance!

 

[Hooty]

Re: How to remove broken gearcase screw?

Oh my.<br />That's not good. If you get the plug out, you can always helicoil new threads in. That ain't the problem. The problem is gonna be gettin' the old one out. That rascal is stainless and harder then woodpecker lips. If you could pull and unscrew at the same time, it would probably back right on out. I'm gonna have to think about this. Lets keep this post at the top and see if anyone else has a solution.<br /><br />c/6<br /><br />Hooty7

 

[old motor]

Re: How to remove broken gearcase screw?

A lesson in preventative maintenance, I guess. I didn't bother changing the gear oil last year, since the motor had very little use. BUT, it does get run in saltwater, so I guess the screw got jammed with corrosion, with the interface of different metals. In future, I must remember to regularly turn all accessible screws and nuts, as well as wash off the motor with fresh water, and perhaps coat these types of threads with Never-Seize as well. Live and learn!<br /><br />BTW, what is a "helicoil"?

 

[Hooty]

Re: How to remove broken gearcase screw?

A helicoil is a thread insert. Drill out the old threads and tap the hole with threads that accomodate the threads on the outside of the helicoil. The inside are the same threads as what you're replacing (1/4-20 or what ever). <br />Here's an idea. I've never tried it and don' have any idea if it will work or not.<br />JB Weld is a two component epxoy that's available at any auto parts house. The head of the plug, screwdriver slot and screwdriver must be really roughted up with course emory paper. After they're sanded good, don't use any solvent to wipe them. Just blow them off and apply the JB Weld. Allow it to cure overnight. If it works, it will allow you to pull and unscrew at the same time, hopefully removing the plug.<br />Someone may have a better idea but right now, I don't.<br />Keep us posted.<br /><br />

<br /><br />g'luck & c/6<br /><br />Hooty

 

[John Reynolds]

Re: How to remove broken gearcase screw?

Hooter, I mean, Hooty is right. Helicoils are standard equipment for automotive use. Work good. <br />But to remove the old screw head? You might try to get something under it, like a sharp chisel edge or filed-down screwdrivwer. leverage up on it and turn it at the same time. You might have to sacrifice a little of the lower end's finish.<br /><br />Hey Hooty, did you ever paint your carbs with Metalcast?

 

[old motor]

Re: How to remove broken gearcase screw?

Thanks for the ideas. I did try the "get something under it" approach at first, but there's no space between the screw head and the case. I'd have to grind off some of the gearcase, and I don't know how thick the wall of the case is.<br />I like that glue idea, and am amazed at Hooty's diagram! I wish I was more computer literate so I could do tricks like that!<br />You've both been a great help already, and I'll let you know how it goes.

 

[old motor]

Re: How to remove broken gearcase screw?

Well, last night's attempt failed. I used your method, Hooty, but with what I had on hand: some "Marine Tex", also a 2-part epoxy. This morning, the Marine Tex had bonded well to the screwdriver, but had absolutely no bond to the face of the screw. I suspect the screw had an oil residue.<br />Today, I went and bought some JB Weld, elevated the leg some more to avoid oil leakage, wiped the screw well with paint thinner, then a clean rag, then isopropanol, then a clean rag, then roughed it up some more with emery paper, and applied JB Weld.<br />I will leave it 24 hours and then report back! <br /> Wish me luck, because I just checked this website for the price of a new lower unit, and it's $1500 !!!!! That's over 2000 of our Canadian dollars !!!! That'll never happen, from my wallet! If I can't get this fixed, I envision this reliable old motor getting tossed in the garbage all because of one stripped screw !!! I am not a happy camper.

 

[Hooty]

Re: How to remove broken gearcase screw?

Another thought.<br />If the JB Weld doesn't work, take the l/u off and take it to a machine shop and let them worry with it. That's gotta be cheaper then the 2 grand for a replacement.<br /><br />c/6<br /><br />Hooty

 

[old motor]

Re: How to remove broken gearcase screw?

Thanks for the idea; that's what I'll do. I was just venting, because the motor should be in use now by guests of mine at my cabin up the coast. Also, I've already had to bring it home for this, and I will need to deliver it back up there when it's fixed, at $100 worth of ferry fares. Grrrrrr! Infernal combustion engines!!

 

[SeaMasterZ@aol.com]

Re: How to remove broken gearcase screw?

a shop would likely use a titanium or diamond tipped bit to drill out the screw and back it out with an EZ out - thats a tough break tho!<br /><br />the picture thing is pretty easy, now that I have figured it out ... hit the img button and paste in the link to the pic, in the case of what hooty did, take the pic, post it to a webpage, then away you go!<br /><br />machine shop shouldnt charge an arm and a leg, just a few fingers and maybe a toe, sure beats 2 grand though!<br /><br />(Im a poet, and I know it ...<br />look at those feet ...<br />Longfellows!)<br /><br />

 

[old motor]

Re: How to remove broken gearcase screw?

Your the man, Hooty! <br />Your ingenious JB Weld technique worked like a hot-damn! I now have on my desk the offending screw and a small pile of metal shavings which came out with it! And my outboard no longer looks like a wierd sculpture with a big screwdriver sticking out of it!<br />Next stop, back to the auto parts store for a "helicoil".<br />THANK YOU!

 

[Hooty]

Re: How to remove broken gearcase screw?

Sierra Hotel old motor!<br /><br />I'm tellin' ya, JB Weld is some good juju!<br /><br />c/6<br /><br />Hooty

 

[old motor]

Re: How to remove broken gearcase screw?

Update from surgery ward:<br /><br />1. Operation successful.<br />2. Patient survived, and wants to go fishing now.<br /><br />Thanks again, motor-people !!! You are the greatest; saved my butt for sure !!!<br /><br />P.S. Hooty, what does "c/6" mean?

 

[old motor]

Re: How to remove broken gearcase screw?

bump to the top, to thank you motorheads !!!