Water Pump Change Yami 90 HP 2 Stroke

[chilipenquin]

Well its time I did this myself so I was going to try to get assistance from the forum and its members.

1. What parts do I need before I start? Gaskets? Impeller?

2. What tools do I need?

3. Drain the oil first?

4. Should I tilt the motor up when I pull it?

Any help would be great fully appreciated.

Chili

[bossee]

Hi,

A good start is to check parts cataloge at Yamaha US site so You can see how it is inside the lower unit:

http://www.yamaha-motor.com/outboard...home/home.aspx

You can buy impeller repair kits (without housing). I would also change to new seals in both ends of water tube (the water tube from impeller housing to powerhead). If You neded you can buy a Yamaha service manual, it is described there how to change impeller.



/Bo

[Door#3]

First make sure you have the parts and materials that you need. Off the top pf my head that includes:
- Impeller kit
- Lower unit oil
- Pump kit for lower unit oil. Make sure you have one that fits the Yamaha drain hole, or the adapter.
- Tools - standard metric socket set (with extender) should do it.

Drain the lower unit oil. I do this by dropping the lower unit, removing the upper vent hole, then the lower drain hole. Having a container with a wide opening helps as the oil sometimes is influenced by surface tension along the skeg as it drains. If I remember, I start the drain the night before I'm going to do the job. That way all the old oil drains out.


For the rest I'll refer you to a post on the FS forum from 2003 titled "Waterpump / Impeller 101 - A DIY how to with Photos" by a poster named Square Grouper. It gives a step by step for doing this on a Yamaha 200. I bet your motor is quite similar. I have a printed copy of this post in my Yamaha service manual. BTW.. you should get a service manual. Even with detailed posts the service manual provides much more, and will help keep you out of trouble.

It's a pretty easy job, so go for it...

[Bigger Hammer]

I'll give you the same story as you've gotten above, but quote some different resources within THT.

Andy with SIM (Shipyard Island Marine, a THT PRODUCTS forum) will set you up with exactly the parts you'll need.

He's also archived a thread started by member HOTSPOT that thoroughly documents the water pump replacement on a F200. The process should be very similar:

http://www.thehulltruth.com/forums/t...145363&start=1

Andy, and others, will provide whatever help you need if you ask for help.

Bill

[debugger]

I usually change the t-stats and the pressure valve at the same time. cheap insurance.

[ESSRTEE8]

Ditto on calling Andy for the parts.

Great guy, he'll set you up with what you need.

You do not have to drain the lower unit to change the water pump.

[Door#3]

Bigger Hammer - 12/27/2008 10:42 AM
He's also archived a thread started by member HOTSPOT that thoroughly documents the water pump replacement on a F200. The process should be very similar:

http://www.thehulltruth.com/forums/t...145363&start=1

Andy, and others, will provide whatever help you need if you ask for help.

Bill

Wow, that's an excellent post from Hotspot. I had not seen that one. I echo the sentiments about SIM, a prompt and reliable supplier.

And for on line Yamaha Service Manuals...
http://www.yamaha-motor.com/outboard...d_manuals.aspx

[Door#3]

ESSRTEE8 - 12/27/2008 10:47 AM

You do not have to drain the lower unit to change the water pump.

True. I always do because it's part of the end of season ritual every other season...