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Tohatsu 2008 9.8 hp A3, Lower Unit oil plugs and gaskets replacement

A

Alex.R

New member
Hello,

I have a 2008 Tohatsu 9.8 four-stroke motor. Changing an oil in a lower unit I stripped a head of a lower bolt. Thanks God I managed to get the bolt out finally but now I need to replace it for sure. And I hope I could find the same bolt with a hexagon head to avoid the hassle in a future. Did anyone see such a plug anywhere? Do they exist in nature?

Looking at the bolts itself I didn't find gaskets or O-rings on them. It's weird because I didn't use the motor a lot, may be 50 hours per season, not more. Is it possible there were no gaskets on the bolts at all? The manual says they have to be changed each time when the oil is changed but I can't recall I did such a thing and can't remember how they look like :(

The main problem is that my closest Tohatsu dealer is about 100 miles away and it looks I am forced to drive there to get 2 gaskets and two new bolts... But there are several Mercury dealers around and I've heard Tohatsu makes motors for Mercury up to 10Hp. Does anyone know if I can use their parts? If no, may be someone knows genuine Tohatsu part numbers for the gaskets and bolts?

Thank you,
Alex
 
Re: Tohatsu 9.8 A3, Lower Unit oil plugs and gaskets replacement

If your screwdriver is too small, it will mangle the drain screws. You need a hefty driver. And don't torque the plugs to death when you install them. Just a little more than seated is quite adequate. Yes, they use a fiber washer as the gasket under the head of the plug. Yes, the thread is a common metric size, so if absolutely necessary (for instance, if the mechanic has severe arthritis), one could install stainless hex head cap screws, as long as the heads don't bind on the housing before the gasket compresses. If the gaskets were missing, a previous mechanic left them out and then tourqued the plugs until they didn't leak too much.

The Factory replacement parts are: 332600060M GASKET $0.57 and 332600052M OIL PLUG $4.28, available from any dealer, including me. Just have your dealer drop them in an envelope and mail them to you.

Tohatsu makes the Mercury motors up to and including 30 hp.
 
Re: Tohatsu 2008 9.8 A3, Lower Unit oil plugs and gaskets replacement

Thank you very much, Paul!
I've used 1/4" screwdriver before but got a 3/8" one to get it unscrewed.
Fiber washers! I thought they supposed to be made of rubber and suspected they just fell apart or deteriorated. I'll watch more carefully the washers might be on a thread, not on the plugs.
I asked my friend who is a mechanic and he made two screws for me but instead of an outer hexagon head he used anodized plugs with inner hexagon heads and they look nice. I'll post a picture when I get them.

The part numbers you kindly gave me, - are these for Tohatsu/Nissan or they're Mercury parts? The last letter M confuses me a bit :)
May I know how could I buy the gaskets from you? Do I call or go online to get 6 gaskets?

Thank you again,

Alex
 
Re: Tohatsu 2008 9.8 A3, Lower Unit oil plugs and gaskets replacement

Be careful. If the new plugs are anodized aluminum, they could corrode in place when in salt water for a while. Likewise, the allen-drive (internal hex) may become an issue if marine growth or corrosion fouls the sockets -- then you may have problems getting a wrench into the heads. There is a good reason why the factory uses stainless with slotted heads.

Those are Tohatsu part numbers.

The parts are available from any dealer, including me. We'd be happy to mail you some bits. You can drop me an email at the office: [email protected] or call me at 716-877-8221 M,W,F 9-5 Eastern (winter hours).
 
Re: Tohatsu 2008 9.8 A3, Lower Unit oil plugs and gaskets replacement

I'd like to get the facts together on my 9.8 and get in on this deal if I may Paul.

Always good to have an extra plug and gasket on the shelf.
 
Re: Tohatsu 2008 9.8 A3, Lower Unit oil plugs and gaskets replacement

Traskblacktail said:
I'd like to get the facts together on my 9.8 and get in on this deal if I may Paul.

Always good to have an extra plug and gasket on the shelf.
Click to expand...
Not a problem. It's what we do. Also, the updated service manual for the MFS 8/9.8 is now available.
 
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