Nervous about changing impeller

swist

Senior Chief Petty Officer
Joined
Jul 1, 2004
Messages
678
1993 Yamaha 225 90deg<br /><br />In the interest of saving myself some money I've been trying to do some of the easier jobs maintenance myself. I have mechanical skills, but not in the outboard arena. I did the tstats. I did the fuel pumps. I did the poppet valve/grommet etc. Now I want to change the impeller (bought a real Yamaha water pump rebuild kit). Reading the Clymer book, I am most concerned about getting the lower unit off and on. It looks to me like when you pull it you will have three really long things to get back from whence they came (shift shaft, water tube, drive shaft). And they all have to magically ride up into the middle unit and seat themselves pretty much blindly - is this as hard as it looks? How can you guide three things into their seats simultaneously when you can't see where they are going???
 

snowmon

Seaman
Joined
Jun 23, 2004
Messages
55
Re: Nervous about changing impeller

hi,<br /><br />drive shaft is the only part that runs up the housing and mates at the block. the water tube and shift shaft actually mate where the lower unit breaks and are easy to line up. just make sure you remove all of the bolts. trim zinc and bolt under that. <br /><br />good luck
 

mattttt25

Commander
Joined
Sep 29, 2002
Messages
2,661
Re: Nervous about changing impeller

suggest you have an extra set of hands. probably good to just have another person there to follow the manual with and assist. my uncle and i did mine the first time together, and between the two of us, we managed.
 

rodbolt

Supreme Mariner
Joined
Sep 1, 2003
Messages
20,066
Re: Nervous about changing impeller

yep<br />] yamaha is about the easiest V configured outboard to changfe a pump on. leave the shifter in netural. remove the trim tab, remove the 14mm hex bolt in the tab cavity from underneath. remove the 3 12mm hex bolts from each side and it will come off. dont forget to dissconnect the speedo tube ats the small rubber tube at the lower fwd edge of the exhaust housing. seach my posts on a 115 and delete the part about the retainer assy. unless your gear case is a replacement and has been updated. some place I posted a step by step procedure
 

fastkenny

Seaman
Joined
Dec 10, 2003
Messages
55
Re: Nervous about changing impeller

I'm in the same boat a you. I just did my twin yamaha 150's by myself for the first time and it was much easier than I expected. Took about an hour for the first on and a little less for the second.<br /><br />Also, look for rodbolt's post about removing and cleaning the rubber dam under the aft edge of the pump plate. There was no mention of it in the Clymer manual, and I would have missed it.<br /><br />It's pretty simple, even for a newbie just take your time.
 

swist

Senior Chief Petty Officer
Joined
Jul 1, 2004
Messages
678
Re: Nervous about changing impeller

Thanks, the Clymer manual does not clearly show what parts stay with the lower unit and which stay with the upper. Seating just the drive shaft looks doable.<br /><br />One other thing - one of the "preliminary steps" is to drain the lower unit oil. Seeing as I just changed it last fall, and if I'm not working any lower than the water pump, then the oil should be sealed in place. Yes/No? So why do extra work?
 

Osprey

Petty Officer 2nd Class
Joined
Jun 19, 2004
Messages
128
Re: Nervous about changing impeller

Its no problem to drop the lower unit without draining the gear oil. It is completely sealed.
 
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