I had a leaking coolant expansion tank since early this year. There would often be a tiny puddle of coolant sitting at the top of the expansion tank, near the bleeder valve. The leak was small enough where I would only need to top up with coolant every couple of months. I had done numerous visual inspections in an attempt to find the source of leak. This included tightening the bleeder valve screw, which didn't help. I suspected there was a pinhole leak somewhere on the top of the expansion tank.
Figuring I would need to buy a new expansion tank, I began looking for one online. While searching, one of the images that popped up was the plastic bleeder valve screw. The picture online had a large o-ring just under the screw head (go to the bputah website and you'll see exactly what I am referring to). Looking at my screw, I noticed the o-ring was closer to the tip of the screw, was much smaller, and was crushed to the point that it was useless.
I removed the old o-ring and put on a larger o-ring that I happened to have that was just the right size. The screw now fits very snug and there is no more leaking coolant!
I should note that I have an '05 LR3. Newer models most likely no longer use the smaller o-ring. Hope this helps somebody!
Figuring I would need to buy a new expansion tank, I began looking for one online. While searching, one of the images that popped up was the plastic bleeder valve screw. The picture online had a large o-ring just under the screw head (go to the bputah website and you'll see exactly what I am referring to). Looking at my screw, I noticed the o-ring was closer to the tip of the screw, was much smaller, and was crushed to the point that it was useless.
I removed the old o-ring and put on a larger o-ring that I happened to have that was just the right size. The screw now fits very snug and there is no more leaking coolant!
I should note that I have an '05 LR3. Newer models most likely no longer use the smaller o-ring. Hope this helps somebody!