Cover Nut tool

[Arkman]

This is a two part question so hang in there.

I'm just about to start pulling apart my lower unit to replace the seals. I' have some water in there after it sat for a long time. First question, should I pull it all the way apart and replace all the possible seals that I got in my kit or are there a few that are more important/easier to fix/more likely to leak that I should try.

Second, if I need to pull it all apart I understand that I need a cover nut tool. I've seen a few people talking about making their own. I just don't understand how they made that tool. Any suggestions?

Oh, its a 1968 Merc 200 (20hp).

 

[coolguy147]

Re: Cover Nut tool

might be a spanner wrnech not sure if mercury of that year used a spanner wrench

 

[Arkman]

Re: Cover Nut tool

No, I dont think thats right. This is what I'm referring to. I have read a bunch of people say they have made their own, but I just even begin to know how to make one.

Thanks

 

[Arkman]

Re: Cover Nut tool

ok, i have another ? What is the best way to remove the left over gunk on from the gaskets you pull off. You know the little bit of the gasket that seems to be fused to the metal. In my carb I just used carb cleaner and a rag. Would that be ok in the lower unit? Should I use something else?

 

[Lion hunter]

Re: Cover Nut tool

GOO-Gone works great on gaskets. I wet the gasket and let it set for a while before scraping.

 

[Arkman]

Re: Cover Nut tool

Thanks Lion Hunter. Is that ok to use on the surface of my water pump? Its a hard plastic. Normally I would use that stuff on plastic but I'm not sure about inside a boat motor.

Thanks again!

 

[7920hpMercury]

Re: Cover Nut tool

I made cover nut tools for 20 and 9.8 a couple of ways.

The best way I think is:
*buy a replacement cover nut so you have a pattern to fit to.
*get a 1-1/2" (think that is the right size, double check, I do not have it in front of me) pipe tee, galvanized, from hardware store and a couple of 1-1/2" pipe nipples, 18" long.
*On straight thru passages on the tee, screw in the handles.
*On the take off in the tee, cut slots to match the cover nut.
*On the back side of the tee, drill a hole to allow the prop shaft to pass thru.
*When you install the tool, use a prop shaft nut to hold the tool in place. This aids in keeping the tool in the slots. Some are left hand threads and some are right hand. I think the 20 is right hand. Check the on/off arrow cast in the cover nut.

Hope this helps and if you go to the trouble of opening up the lower unit and you buy a seal kit, I would go ahead and replace all of the seals while you are in there. Good luck!

 

[Arkman]

Re: Cover Nut tool

How do you cut that pipe. I my biggest issue is I dont really have any way to cut that pipe. I guess I could use a hack saw. How tough is it to cut?

Another ? Is it ok to use WD-40 on the nut. Thats all I have at home right now. I would imagine it would be ok, just thought I would check.

 

[Arkman]

Re: Cover Nut tool

Well, I ran to a shop in town over lunch and the guy there got it loose for me. So thats cool. Now tonight I just have to replace a few more seals and hopefully be back on the water.

 

[Lion hunter]

Re: Cover Nut tool

Goo-gone is petroleum based product so there should be no harm on plastic or rubber.