Stripped lower unit oil level bolts

M

matt_unique

New member
Well the "oil level" bolts on both engines are stripped at the head. In fact, I narrowly avoided a trip to the emergency room last week. I was trying to turn the bolt to check the lower unit oil level and a piece of the bolt head snapped off and broke the skin on my face. Thankfully it did not hit my eye.

It was 52 degrees so I'm a bit surprised the head grooves snapped. So to be clear, the bolt is fine just the head where you put the screwdriver is too wide for my screwdriver to get any bite. Frankly I could run out the season and worry about it at the end of the season (I topped off the lower unit oil chamber from the vent hole above) but I'm curious what kind of options I may have.

Lesson learned not to turn the lower unit bolts a bit too snug.

Thanks
 
The "fix" that comes to mind first is to drill a hole as deep and as large as you can directly into the center of the head of the screw WITHOUT penetrating the oil reservoir or hitting the hole threads. Then, use an EASYOUT, it's a screw extractor device that tightens as you turn it in a CCW direction and the bolt should back right out.

Charlie
 
you may be able to git it out with an impact driver and a drag link socket. A drag link socket is a very wide screwdriver bit that fits on a ratchet, impact drivers are money well spent for sticky hardware...cheap ones like below, work good for occacional use then the bits go south....not that there's anything wrong with going south.
metal and eyeballs, bad combo.

http://www.northerntool.com/webapp/wcs/ ... 6882_36882
 
Get a bigger screwdriver; I use one that's probably 14-16" long. Depending on how much of the head is left, a properly sized screwdriver might still get it out.
Al
 
Like Moose I use a very large screwdriver but find the thickness of the tip still not quite thick enough. I filed the tip down about about 1/8". The end of the screwdriver gets wider and thicker as you file it down-then you end up with a good snug fit in the very wide slot of the drain plug.

What is a drag-link anyway?
 
Matt - Ah, the joys of boat ownership. Charlie's advice is sound. Only problem is getting the drill centered and not penetrating the plug putting chips into the gear box. Of course you should use a center punch to get started. And the fact that you will be using a hand held drill won't help matters either. My advice is this. The replacement plugs will tell you how much depth you can go in your drilling. If I recall, the plugs aren't very deep, which makes it tricky. If you happen to penetrate all is not lost. Of course your gear box is still full of oil. The drilling process tends to move the chips away from the end of the drill. Plus when you finally get the bugger out, the oil should help drain out any chips Final advice.
Put some anti-seize on the threads of your new plugs. Good luck!
John
 
Matt,

I have used a thin cutting bit on my Dremel and made a deeper slot in the drain plug. This allows my screwdriver to bury deeper and get a good bite. You can replace your plug with an aftermarket type that requires a hex bit to prevent stripping the slotted heads in the future.

George
 
Matt,

I have used the same impact driver since the 60s when all the Japanese motorcycles were put together by 300# gorillas! A light tap on the end loosens any and all screws, plugs, etc. As you tap it, the screwdriver tip is pushed firmly into the slot then turned to loosen.

As far as the old one, an easy-out seems to be the best answer so far. Grease on the end of the drill will help grab some of the chips if you drill through. Good luck.
 
Matt,

I would avoid drilling thru the screw! Stainless steel chips will really mess up the bearings and gears in the lower unit. If they fail, the repair will be more than having the lower unit taken apart at the shop, and having the screw removed from just the case.

As you have found out, the screwdriver MUST fit the slot!!

Solution....Buy a replacement screw, find a Snap On or Mac tool dealer (ask a mechanic at a local car dealer) and buy the proper size screwdriver ($$) that fits the screw slot snugly. At the same time, buy a proper size screwdriver socket (3/8 drive) and use a torque wrench to tighten the screw to the proper torque. The torque setting should be in the shop manual. An option to the screwdriver socket could be an impact driver bit. An impact driver and bit can also be used to remove the chipped screw. Warming the case with a propane torch may also help.

A large mechanics screwdriver will have a hex on the shaft next to the handle so you can press the screwdriver into the slot and turn the screwdriver with a wrench.

It is a good idea to have drain and fill screws and gaskets on hand and replace any screws that are damaged during removal. A screw that is damaged during removal can often be reinstalled, but may be a bi**h to remove the next time. Gaskets should be replaced every time.

The proper tools are not cheap, but paying a shop 3 or 4 hours for labor to remove the broken screw is not cheap either!

Larry H
Retired outboard mechanic.
 
Blue~C

It was nice meeting you at the Kalama Boat launch last week. Thanks for taking some time to show me your C-Dory and explain all my stupid questions. Good luck fishing for the Springers! I hope to catch one or two in the coming weeks!

Hope to see you on the CR before you head North.

Ed
 
Phew...just spent 12 hours washing, scrubbing, waxing, and buffing Napoleon. I need to go to work tomorrow to have a break! Ha!

Thanks for the suggestions all. I too am very nervous about drilling and having any possibility of FOD getting into my lower unit.

I will look into getting a larger screwdriver and possibly using the Dremel to make a deeper slot.
 
So, how do you propose to take the screw out with an impact wrench when the head is broken off??

marvin4239":rimlzzq7 said:
Matt as a couple have already mentioned and impact driver will take the screw right out. Harbor Freight has them for less than $10.
Click to expand...
 
Pat Anderson said:
So, how do you propose to take the screw out with an impact wrench when the head is broken off??


Unless the head is broken completely off the pressure on the remaining stud from tapping on the impact driver will usually lossen the screw. Notice we are talking about and impact DRIVER not and impact Wrench. If you aren't familiar with impact drivers they generally have different size and type tips. When you put the tip on a broken stud and tap on the driver it makes a twisting motion which lossens the screw similiar to using a wrench on a square shank screwdriver. Like Dreamer said I've been using these since the 60's also and just used mine about three weeks ago to remove a 8mm stainless screw from my motorcycle that the head was completely gone on.
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Thanks gentlemen.
My bolt head is not completely broken off, but stripped in terms of my existing (largest) screwdriver. Imagine a bolt that requires a nickel instead of a dime to fit in. Of course the edges are also a bit rounded from the material that broke off when I tried to remove them.

I'm splashing the boat Sunday to drive it to a boat yard. They will haul it out and set it on blocks to allow me to touch up the very bottom of my sponsons. Once there I will try again and check out these other tools/options suggested.

Thanks again.
 
Pat Anderson":9i8d9z2h said:
So, how do you propose to take the screw out with an impact wrench when the head is broken off??

marvin4239":9i8d9z2h said:
Matt as a couple have already mentioned and impact driver will take the screw right out. Harbor Freight has them for less than $10.
Click to expand...
Click to expand...

We're not talking LUG NUTS here Pat. :shock: :lol:

Charlie
 
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