TOPIC:

Can anyone tell me roughly how long it will take from start to finish to replace the water pump seal,

Also any tips or things to watch out for,   I’ve seen a photo of a homemade impeller puller,  are the impellers likely to break if seized on?

Any info would be great,

Thanks Pete,

Hi Pete,

How long? When I did it I would guess 4 to 6 hours. I pulled my impeller using two needle nose vicegrips. Be forewarned the vanes on the impeller are VERY brittle. I was successful, no damage to the impeller.
Things to watch out for: Don't let the but end of the vice grip doink the back side of the front fender when the darn thing decides to come loose.
Good Luck
Bill

4 to 6 sounds about right. I was able to swap mine out in an afternoon.

• A special impeller puller isn't usually necessary, unless the engine has sat for a LOOOOONG time. Even then, I pulled the impeller on an engine that had set, and it still came off pretty easily.
• You WILL need some type of liquid gasket compound. Yamabond/Hondabond/etc. This is used between the seal and the holder, and between the holder and the engine.
• In addition to the mechanical seal, there's also an o-ring between the lower impeller housing and the block, along with the two o-rings on the bypass tube. They can probably be re-used, but they aren't too expensive if you want to replace them as well. There's also a small o-ring on the end of the water pump shaft- again, might be able to to be re-used, but may as well replace it if you can get to it.
• You'll need a pair of pliers to remove the circlip holding the impeller on.
• Behind the mechanical seal is an oil seal where the impeller shaft goes into the crankcase. This is an excellent time to replace this as well, if you're having issues.
• There are a pair of Phillips screws that are probably frozen. An impact driver REALLY helps here. Otherwise, smack the top of them with a correctly sized punch and hammer to break them loose, then use a screwdriver to remove them.

Overall, it's not a bad job. Despite the list, it's actually a pretty straightforward and easy job. Good luck!

Thanks Guys for the info,
All the engines I've had apart before have always been air cooled so this is a first time to replace a MECHANICAL seal. I've just read up a bit on the idea behind them working, So my question is, do I need to use any special lubricant on the shaft and seal, and do they leak a little before its run in for a while??

Thanks Pete.

I put mine on dry. The main thing is to keep the ceramic to ceramic seal (one in the back of the impeller, one on the housing) as clean as possible.

It should seal right away, or very soon after it's put in. Keep an eye on the weep hole, but my problems cleared up nearly immediately.

found this, crap music and crap video but it gives you an idea of what you will be doing..