Coolant Breather Tube Mod

[Thrasher]

I found this info on another board, I do not remember where, I take no credit nor do I know the accuracy of the info. (not that i have reason to doubt it!)
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Coolant Breather Tube Mod

Here's a couple of modifications that will help to keep your engine coolant clean which will pervent premature coolant pump seal failure. These are recommended modifications if you do a lot of mud or submerge your ATV in any substance. Special thanks to Tru4wd for posting this writeup.

There are 2 areas that need attention.

1. The overflow bottle has a small hole in the top that draws in muddy water when the engine is cooled as it would be going through a mud hole. This contaminates the coolant and will in time damage the water pump seal.

The Mod

Find a piece of clear Tygon (plastic) tubing of no more than 1/4", you will also need to find/make a hose connector that will fit snuggly into the tubing.
Drill the out the hole large enough to insert the hose connector and fix it in place (no leaks) then attach the Tygon tubing to it and run the other end up to the the air intake tube and hold in place with a tie wrap.

2. (Most important) The main reason the water pump seal fails is contamination from muddy water entering the weep hole under the seal. Muddy water has direct access to the seal via this hole.

The Mod

Find a piece of 1/4" metal tubing (I used stainless steel) about 1" long and about 2 foot of 1/4" Tygon (plastic) tubing.
You will need to taper one end of the metal tubing for approx 1/4" so that it fit's into the weep hole. With a little 5 min epoxy applied to the tapered end, place the tapered end into the weep hole and with a small hammer gently tap into place until snug. Allowing 15 mins for the epoxy to cure properly, slip one end of the Tygon tubing on to the newly made hose connector and run the other end up behind the engine to the frame. Tie wrap at 4 to 6" higher than the weep hole and the let the end hang down at a convenient location.

Most automotive parts stores carry clear plastic tubing and a variety to connectors that can be addapted to do the job.

Edit: The best connector I have found so far is a small threaded grease zerk (threaded 1/4" x 28 Fine Thread). Remove the check ball and spring by clamping the zerk in a vice or locking pliers, and filing away on the BACK side of the zerk until the spring and ball can be removed. Tap the overflow bottle lid or weep hole to 1/4" fine thread (a few guys have even managed to thread the weep hole without drilling it bigger. If you do drill, be VERY careful not to drill too deep). Thread in the zerk firmly, and you have a ready-made nipple for 1/4" tubing, just push it over the zerk, and zip-tie it on. It is important to remove the check-ball to allow for unrestricted venting.