To help everyone out, I thought I would document how to change an oil seal and & water pump mechanical seal on a mid-2000’s twin cylinder engine…WITHOUT special tools from Polaris.
Fluid coming out of the weep hole on the bottom of the water pump housing indicates that one of these seals is bad. The weep hole originates about 2.5 inches into the housing between the oil seal and the water seal. There is a very narrow cavity there that allows fluid to escape through the bad seal and out of the engine. If both seals go at the same time, there is the possibility they will mix and you will have oil in your coolant or vice-versa.
The oil seal is mounted in the crankcase behind the water seal, which is in the stator housing. Since they are on the same shaft, changing the oil seal requires changing the water pump seal as well. You could avoid this and save about $25 by taking the stator housing off. Even then, you might still damage the water seal and have to change it anyway. I would rather not mess with the stator if possible so I elected to change both.
This took about 2.5 hours, which included about a half-hour of rounding up buckets and tools that were "borrowed" by my wife and kids--and of course, not put back in my tool box.
Parts I used for a 2006 700 EFI Twin:
2.25 quarts antifreeze
About 8 ounces of oil
5412455 Seal, Oil $25.28
3610075 Seal, Water Pump $42.99
5812571 Seal, Cover, Water Pump $3.79
7546804 Nut, Hex, Nylok $0.61
1. Remove the right knee panel and footwell & remove the radiator hose from the pump to drain the coolant.
2. Remove the black plastic cover on the stator housing. It’s only 5 bolts as indicated by the empty holes around the edge.
3. Remove the water pump housing noting the location of the two longer bolts. When you pull the housing off, a bit more coolant will come out.
4. Remove the nylok nut and metal washer from the end of the shaft and pull the impeller off. Inspect the impeller for nicks, cracks, and any worn spots on the vanes. If you suspect any damage at all replace it; it’s less than $20.
NOTE: At this point you are at the water pump seal assembly. If you were leaking coolant, this assembly could be in various states of disarray. My instructions assume a good seal.
5. Grab the rubber/ceramic washer that was behind the impeller and pull it off. This is part of the water seal assembly and the only part you will see on the parts diagram. The diagram shows this washer on the outside of the impeller, which is incorrect.
6. Now pry the spring out of the water seal assembly. You might have to use a good bit of pressure. Be careful you don’t gouge the shaft or the mating surfaces on the stator housing. You should now be looking at a copper colored metal cup.
WARNING: In the next step, you are likely to damage the oil seal when you punch through the water seal with the drill. If not the drill, then the screws will do it when you put them in. In fact, I would plan on replacing the oil seal. Just remember, even if you replace both seals you are still saving lots of money on labor.
7. Now pull the copper cup out. To do this, drill a small hole on opposing sides of the cup and turn a 3” screw into each hole just far enough to get a bite on the cup. To do the pulling, I used a steering wheel puller to make sure I pulled straight out and to prevent lurching in the event the cup suddenly gave way. You can pull the screws with pliers as long as the copper cup comes straight out. Again, be careful not to nick the shaft.
8. Now that the copper cup is out you can see the sludge and dirt that was behind it.
9. Remove the oil seal the same way as the copper cup. Behind the oil seal is a bearing race. You will hit it with your drill but it won’t be damaged unless you let the drill linger there. Make the holes opposite each other and about halfway between the inner and outer edges of the oil seal. Note the broken retainer spring that caused the seal to fail.
10. With both seals removed you can see there is sludge. Clean out the area of sludge and coolant paying special attention to where the seals will go. Here is mine, not yet cleaned.
11. Install the oil seal. Put a thin layer of motor oil on the outer edges of the oil seal and push it into place by hand with the flat edge toward you. It won’t go near all the way in but it will be ready for you to tap it the rest of the way. I used a 27mm socket, but I wished I had a 28mm to be closer to the edge. Even better, I would first like to have placed a washer big enough to cover the entire outer edge of the seal rather than have socket-to-seal contact. Anyhow, gently…and patiently…tap the seal into place until it is flush with the metal lip. This lip only sticks out about 1mm, if that.
12. Run a pipe cleaner or suitable substitute through the weep hole gallery to clean it out. There is likely a lot of trail dust in it. To keep it clean, I have read where some folks have drilled out a grease zerk and then tapped it into the weep hole. Then they run a length of rubber tubing high enough to keep the end above water. Mine is stock and worked as advertised after 5 years. Here you can see the inner end of the weep hole below the shaft. Guess the camera was too close.
13. Now take the water seal out of its package. The plastic cover is for shipping and it fits into Polaris’s special installation tool. Remove it by snipping the edges with wire cutters until it falls off. The assembly is spring loaded so be careful not to drop the rubber/ceramic washer as you take the cover off…the ceramic could crack or chip. Install the water seal using a 32mm socket. It must be a 12-point socket versus a 6 point socket in order to have enough clearance on the inside. Oiling the edges of the water seal is not necessary. It has gasket sealant on it already.
This seal is a little more difficult to get started. You have to hold the seal assembly in the socket rather than starting the seal by hand. Now, just like the oil seal, gently…and patiently…tap the seal into place until the flange contacts the metal lip. BE SURE YOU ARE PUSHING IT STRAIGHT IN!
14. Place the rubber/ceramic washer on the shaft with the rubber side out. Now install the impeller, metal washer and new nylok nut. Torque it to 108 in-lbs.
15. Clean and dry the mating surfaces for the water pump housing seal and install the housing with a new seal. The manual says to install the water pump housing seal dry; and NOT to add any lubricant or gasket sealant. Put Loc-tite on the bolts and torque them to 108 in-lbs, making sure to replace the long bolts in the correct position. If you forgot, they go into the larger diameter holes.
16. Attach the radiator hose and fill the radiator with coolant, leaving the cap off.
17. Add oil if necessary.
18. Start the engine and check for leaks near the water pump. If all is well, allow the engine to warm up and add coolant as necessary, milking the lower radiator hose with your hand to purge the system of air. Repeat this cycle (add, milk, add, milk…) until the radiator is full and the coolant reservoir is at the appropriate level. Replace the cap.
19. Reinstall the stator housing cover, the footwell, the knee panel and the seat. Congratulations! You are done.
Hope this removes some doubt for those of you that were thinking about doing this.