1992 25hp Yamaha-Lower Unit Oil Seals

[jim25]

I had water in my lower unit this fall. I would like to replace the 2 oil seals on the prop shaft. I have removed the lock nut but can not get any father. It appears the casting holding the seals would screw out but I am afraid of breaking something. Am I on the wrong track?<br /><br />Thank-you<br />Jim

 

[JB]

Re: 1992 25hp Yamaha-Lower Unit Oil Seals

Yamaha Troubles

 

[rodbolt]

Re: 1992 25hp Yamaha-Lower Unit Oil Seals

hello<br /> there is a small puller with J-bolts that hook on the bearing carrier. if you use a jaw puller on the thin ring at the aft end of the carrier it will break.<br />do you have a service manual ?

 

[rcgt78]

Re: 1992 25hp Yamaha-Lower Unit Oil Seals

Hi there!<br /><br />Are you sure it's the prop shaft that leaks?<br /><br />I had my 20hp -87 lower unit for a pressure check today. The unit was leaking air at the seal around the shaft under the impeller. And also at the gearchanging linkage. The prop shaft was not leaking.<br /><br />Ordered new seals and will change them soon.<br /><br />Robbi

 

[rcgt78]

Re: 1992 25hp Yamaha-Lower Unit Oil Seals

How are you doing with changing the oil seals?<br /><br />I got the parts for my 20Hp and it appears that<br />I have to remove the prop shaft in order to be able to change the seals around the shaft to engine. <br /><br />But I can't get the lock nut removed. Is it like an ordinary nut that is opened in the usual direction? Any tricks to get it opened?<br /><br />B.R.<br />Robbi

 

[rodbolt]

Re: 1992 25hp Yamaha-Lower Unit Oil Seals

Robbi<br /> a werd o ad vice<br /> destroy the nut.<br /> drill it in 3 places without allowing the bit to walk into the case threads. you will have to have the correct spanner wrench to reinstall it. dont pull the carrier by the flange with a jaw type puller. you should use a J bolt style puller. most times corrosion has that nut locked and most times if you force it you break the case.

 

[rcgt78]

Re: 1992 25hp Yamaha-Lower Unit Oil Seals

Thanks for the advice!<br /><br />It's very often so that one has to destroy something to get to the part that actually requires service!<br /><br />I have to try to get it off without breaking too much.<br /><br />By the way, what does the correct spanner wrench look like? Where can I found pictures of a jaw type puller and a J type puller? <br /><br />Robbi

 

[rcgt78]

Re: 1992 25hp Yamaha-Lower Unit Oil Seals

I got the Clymer manual now and found illustrations of typical tools needed to remove the shaft.<br /><br />This book is really something that I should have bought a long time ago. <br /><br />I will report later how I manage with the service, because the information can be valuable for somebody else. <br /><br />Robbi

 

[rcgt78]

Re: 1992 25hp Yamaha-Lower Unit Oil Seals

I have now the boat in water and it runs great!<br /><br />Had to destroy the lock nut by drilling holes in it. I built a J-puller in order to remove the bearing carrier and propeller shaft. Also the pinion gear was a little tricky to remove. With all shafts removed I changed the oil seal on propeller and drive shafts, gear linkage rubber boot, impeller and all gaskets. Put everything together and filled the gearcase with oil. <br /><br />Hopefully the oil will look fine next time I change it!<br /><br />Thanks!<br /><br />Robbi