300 evo 4T water pump

[lotus54]

I found one thread on this- but it wasn’t really clear to me. I have not had any experince with these engines yet.

I believe I am due for a water pump seal replacement. Perhaps the shaft should be replaced at the same time. I could not discern if the water pump shaft can be removed without the gear driving it being disturbed. It appears that the engine needs to be at least pivoted down to remove the cam cover, and probably that would be the safer way (?) but who has done it ‘in sutu’ and just removed/replaced the shaft and seals?

thanks for any help.
Mark

[kiki]

what year is your bike?

[lotus54]

2016

[kiki]

I am new here, but i I have 30 years wrenching on bikes (with several as a shop tech). I saw your post and was curious, so i downloaded the 2012 service manual for that engine. I assume you have the DVD for the 2016 , which may have some variations. I have ridden the 2016, and it setup looks familiar to the one i downloaded (specifically the attachment points and general space). And the parts diagram between the 2016 and 2012 look the same. There may be a trick to servicing the pump shaft with the engine in the bike, but the manual , i believe, suggests removing the engine.

for 2012, the impeller shaft is run off the cam shaft. the impeller is removed fairly easily, but its drive shaft requires a tool to unscrew it from the attached gear. There are 2 bearings supporting the shaft on either side of its drive gear, so logically, when you pull the shaft out, the gear would succumb to gravity, and fall somewhere south of its normal home. This wouldn't be a big deal if you were dissembling the whole engine top end. Judging form the photos in the manual, the shaft seal would be more challenging without removing the shaft first..but. there are lots of tools available to remove a seated seal on a fixed shaft like that. The cheap tool is a slide hammer with a screw tip. commonly used it for counter-shaft seal removal. I would assume it would work fine there, since i referred to the parts diagram for your bike.Once the old seal is out, you would need a seal driver to put a new one in (or a deep socket of appropriate size.  So if you could drain the coolant and tip the engine forward enough, you could really shortcut the whole process. That being said, if the seal is bad,  you would know (milky oil).

If you are replacing the shaft, I would suggest following the manual and hauling the engine.

 

 

[lotus54]

No water in the oil-  I did see some drips out the ‘weep’ hole in the water pump.

 Since there are two seals, it can leak out but not into the oil (so I understand).

It hasn’t seeped any more, but I have the parts (to be ready).  Thanks mark

[lotus54]

I still have not seen any more weeping, and the coolant level has been good.

Perhaps it was just not happy going from hot Arizona to cold NW Washington state!  Rebelling against the snow.

 

mark