Water pump install - girls can turn wrenches too

[Missxena]

This week I received my new water pump kit from this web site,
so today I thought I'd try installing it. Have owned this boat
5 years so decided to replace top/bottom housings, all gaskets, and impeller.
Not to mention it wasn't "peeing" like it should.

The pump kit install was easy. I have a Seloc manual, but
also paid attention to how the old items were assembled.
The biggest pita imo was re-aligning all the stuff when you
re-install the LU.

Well the water pump now pees like a race horse even with
just the earmuffs in the driveway, but I don't think I aligned
the shift shaft properly since I hear a clicking when I turn
the prop clockwise in fwd gear.

Have a friend coming over later this week who knows what
he's doing and will have him show me the right way, or at
least the easiest way to align this thing. Anyway, I found
the re-install of LU the biggest pita of the entire job.
Not sorry I attempted this. I learned a little bit about the
motor today.
Here's a picture of the old impeller for your enjoyment.
Notice the torn portion under my index finger, not to mention
the impeller looks totally distorted. It was definitely time
to replace I'd say.

Motor: 89' Mariner 3cyl 50 HP, I purchased in 2002

 

[AMD Rules]

Re: Water pump install - girls can turn wrenches too

Catchy subject title...made me look

You've got it all done AOK.

In NEUTRAL prop freewheels in either direction.

I FWD gear, prop will not turn CCW and will ratchet (the noise you heard) when turned CW.

In REV gear,the prop won't turn either direction.

You're all set!

Hint: when re-assembling the lower unit to the midsection it helps to have an assistant turn the flywheel a little bit to engage the splines easier. Its hard to line up the water pump tube, shift shaft AND get the drive shaft lined up without assistance. Not that it can't be done, it just takes a while and can get frustrating.




.

 

[Missxena]

Re: Water pump install - girls can turn wrenches too

Catchy subject title...made me look

You've got it all done AOK.

In NEUTRAL prop freewheels in either direction.

I FWD gear, prop will not turn CCW and will ratchet (the noise you heard) when turned CW.

In REV gear,the prop won't turn either direction.

Thank you for clearing that up for me.
It does all of that just like you explained.
Maybe I should take it out to the lake and give it a test run.

Here's an obiligatory pic of my boat. It's an 87'
Grumman Challenger with the Mariner 50 hp.
My brother and I gave it new decks frt/rear,
new carpet, new seats, in the summer of 03.

 

[kellyisu]

Re: Water pump install - girls can turn wrenches too

I wish I could show you a picture of an impeller I changed out at the begining of summer. I bought a boat with a '79 40hp Merc that hadn't been ran in a year, but was told it ran fine last time used. First few times I took it out it ran for about 20-30 min then died and took a while to get started again. Finally diagnosed the problem when I felt the tel tail stream, which was close to steaming hot. It still was shooting water out fine but nothing like it is now, like you said "like a race horse" after I changed it out. My impeller was so chewed up that there wasn't a single impeller blade intact. There were a few that still had half. Makes me wonder how long it had been since that bugger had been replaced. I keep it in the boat to show my buddies. Maybe I'll put a pic of it on here sometime this week.

 

[Missxena]

Re: Water pump install - girls can turn wrenches too

AMD Rules you were right. I took the boat out on the lake
today and everything is perfect! Dayyyum am I happy I
did this right the first time!

 

[AMD Rules]

Re: Water pump install - girls can turn wrenches too

Glad to hear it. Happy fishin.

 

[BAYLINER185]

Re: Water pump install - girls can turn wrenches too

A 1st time water pump impeller change is a fun learning project.

Its also a bit nerve rackign when you cant get the lower unit all the way back onbecause the shift shaft isnt ligned up right. Then you figure it out and your all good.

I plan on doing my new boats pump next season.....

 

[Scaaty]

Re: Water pump install - girls can turn wrenches too

I was over at my Merc Guru last week...we were discussing impellers. The problem here (and the impeller shown)..is that while it seems a good idea for thick, stiff blades, its just the opposite ya want, as the stiff takes a set too easy. My old 350 raw water cooled original impeller (Sherwood/Jabsco...run off the motor belt) had long thick blades..6 I think, and saltwater finally ate the bushing. Bought a new pump (OUCH...EXPENSIVE!), and this one had 12 thinner smaller blades...runs a solid 140 degree now, and still looks good yearly. The old Merc thick impellers take a set REAL easy, and should be replaced yearly..or at least looked at (but while out, $20 has a new one in anyway....

 

[wilde1j]

Re: Water pump install - girls can turn wrenches too

The trick with the shift shaft is DON'T TOUCH it while the lower unit is off. If you mess with it, it will never be aligned correctly when it's time to re-assemble!

 

[Navy Jr.]

Re: Water pump install - girls can turn wrenches too

Nice work. I am duly impressed.

Just out of curiosity, what is the main cause of these impeller failures? It seems they are a common occurrence.

 

[Nandy]

Re: Water pump install - girls can turn wrenches too

There is something about seeing ladies with wrenches, driving trucks or heavy machinery that makes my heart happy!
Congratulation in a job well done. My trick is to replace the lower unit by myself is using a hydraulic jack. After making sure the shift shaft is in the correct possition I pull the lower unit up as far as I can get it, then set the jack under it. I jack it a bit, just enough to put some presure, then i move the flywheel with one hand. You can generally hit it "click" in possition, then I use my hands again to take it as far as it will go. Most of the time it goes all the way up at that time.
I change my impeller every 1 to 2 years, whatever it looks fine or not.

Navy Jr, I think most of the impeller failures come from lack of maintenance. Just like your vehicle tires, they have a limited life. But unlike your vehicle tires, you cannot see your impeller every time. The tell tale is not enough to tell you there is something wrong, sometimes it does, but it is a mistake to wait for the tell tale to show any signs of trouble to then change the impeller. This is a very common mistake among boaters.
The cost of an impeller is so low and the down time is so short that when compared to the cost of replacing pistons, cylinders, cylinders head and the down time you will experience that it is almost a sin not to change it every 2 years or less.

 

[Scaaty]

Re: Water pump install - girls can turn wrenches too

Nice work. I am duly impressed.

Just out of curiosity, what is the main cause of these impeller failures? It seems they are a common occurrence.

Plain and simple not changed every year or two..run through a little sandy shallow water toast them easy..and the "I just fired it so I maked sure it would start before the launch"...without water of course..heat builds up REALLY fast without the water for lube..

 

[AMD Rules]

Re: Water pump install - girls can turn wrenches too

Here's an illustration of the type of damage than can occur as a result of dry running:

 

[Motor Boater Bill]

Re: Water pump install - girls can turn wrenches too

Great post, AMD! Thanks!

 

[SandMan*]

Re: Water pump install - girls can turn wrenches too

I'd like to inquire about the shape of the impeller.

I keep seeing 2 different designs for these things, ie. Straight impeller vanes and curved ones.

Are these just 2 styles, or are the curved ones worn out?

 

[Missxena]

Re: Water pump install - girls can turn wrenches too

Sandman, the impellers have the straight fingers out
of the box. When you compress the top pump housing
down over the impeller, the fingers become curved.
They have to in order to fit inside the housing.

 

[SandMan*]

Re: Water pump install - girls can turn wrenches too

What are the impellers made from?

I'm very comfortable with mechanics, but I'm new to outboards...

 

[Missxena]

Re: Water pump install - girls can turn wrenches too

They're a hard rubber compound.
Somewhere on here I saw this how-to
and saved it. Shows some great pics
and explains alot.

 

[SandMan*]

Re: Water pump install - girls can turn wrenches too

Just from seeing pictures of them I assumed they were cast aluminum, I didn't expect rubber to hold its form like that or crack the way they seem to.

Rubber explains everything haha... thanks Xena