The bike seems to be leaking what appears to be coolant out of a very small hole in the water pump cover. I know my street bike has a similar hole, and it is the weep hole so when the mechanical seal begins to fail, the coolant runs out of the hole instead of running into the crankcase.
The bottom end oil isnt all milky like it is getting any coolant into it.
My question is, since these bikes dont have a mechanical seal, why would there be a weep hole? and more importantly, why would it be leaking?
Small hole in bottom of water pump cover
- NightBiker07
- Posts: 1942
- Joined: April 16th, 2008, 8:59 pm
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- Location: USA
Small hole in bottom of water pump cover
2000 CR250, pipe, filter, Vforce
1980 XL80s
1969 Broncco TX-6
Natural selection favors Smart people, so nature selects morons to be slow and dumb for tigers and stuff too eat. But in our modern world there just aren't enough tigers.
1980 XL80s
1969 Broncco TX-6
Natural selection favors Smart people, so nature selects morons to be slow and dumb for tigers and stuff too eat. But in our modern world there just aren't enough tigers.
- dannygraves
- Posts: 8020
- Joined: June 1st, 2007, 2:03 pm
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- Location: Las Vegas, NV
there are 2 seals, each on one side of the weep hole. One is for coolant and one for oil. I had a bike where a previous owner plugged the weep hole, instead of fixing it right, so coolant blew past both seals and mixed with the oil. You will atleast need the seal and possibly the shaft and oil seal and bearing. In the past I have hooked the waterpump shaft to a power drill and used some very fine grit sand paper to smooth out the grooves.
Nick had the issue with his bike where the weep hole kept leaking even after replacing everything. it turns out his radiators were plugged and his overflow tube was pinched so the system built up so much pressure that it blew past and good seal.
Nick had the issue with his bike where the weep hole kept leaking even after replacing everything. it turns out his radiators were plugged and his overflow tube was pinched so the system built up so much pressure that it blew past and good seal.
'09 kx450f 4-Poke
Gen-4 trail bike --SOLD--
Gen-3 badass trail/mx bike --SOLD--
Gen-1 built dunes bike --SOLD--
'05 klx110 --SOLD--
'95 pw80

Gen-4 trail bike --SOLD--
Gen-3 badass trail/mx bike --SOLD--
Gen-1 built dunes bike --SOLD--
'05 klx110 --SOLD--
'95 pw80

- freeride588
- Posts: 418
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- NightBiker07
- Posts: 1942
- Joined: April 16th, 2008, 8:59 pm
- Last active:
- Location: USA
I see how it works now. I thought the hole was in the very outer of the cover, but it isnt. It leaks when the bike just sits there, it makes a very small spot on the ground after a few days. I can ride it all day and barely lose any coolant, so it isnt too bad yet. I will get the stuff ordered after i tear it apart and see if the shaft is grooved
2000 CR250, pipe, filter, Vforce
1980 XL80s
1969 Broncco TX-6
Natural selection favors Smart people, so nature selects morons to be slow and dumb for tigers and stuff too eat. But in our modern world there just aren't enough tigers.
1980 XL80s
1969 Broncco TX-6
Natural selection favors Smart people, so nature selects morons to be slow and dumb for tigers and stuff too eat. But in our modern world there just aren't enough tigers.
dannygraves wrote:there are 2 seals, each on one side of the weep hole. One is for coolant and one for oil. I had a bike where a previous owner plugged the weep hole, instead of fixing it right, so coolant blew past both seals and mixed with the oil. You will atleast need the seal and possibly the shaft and oil seal and bearing. In the past I have hooked the waterpump shaft to a power drill and used some very fine grit sand paper to smooth out the grooves.
Nick had the issue with his bike where the weep hole kept leaking even after replacing everything. it turns out his radiators were plugged and his overflow tube was pinched so the system built up so much pressure that it blew past and good seal.
I wonder how much time will pass before you get another 500....because I can tell you miss em. All yur shit works too well (for now). You need something to wrench on.

The CR500 is an acquired taste. If you don't like it, acquire some taste...


- dannygraves
- Posts: 8020
- Joined: June 1st, 2007, 2:03 pm
- Last active:
- Location: Las Vegas, NV
hoofarted wrote:dannygraves wrote:there are 2 seals, each on one side of the weep hole. One is for coolant and one for oil. I had a bike where a previous owner plugged the weep hole, instead of fixing it right, so coolant blew past both seals and mixed with the oil. You will atleast need the seal and possibly the shaft and oil seal and bearing. In the past I have hooked the waterpump shaft to a power drill and used some very fine grit sand paper to smooth out the grooves.
Nick had the issue with his bike where the weep hole kept leaking even after replacing everything. it turns out his radiators were plugged and his overflow tube was pinched so the system built up so much pressure that it blew past and good seal.
I wonder how much time will pass before you get another 500....because I can tell you miss em. All yur shit works too well (for now). You need something to wrench on.




'09 kx450f 4-Poke
Gen-4 trail bike --SOLD--
Gen-3 badass trail/mx bike --SOLD--
Gen-1 built dunes bike --SOLD--
'05 klx110 --SOLD--
'95 pw80

Gen-4 trail bike --SOLD--
Gen-3 badass trail/mx bike --SOLD--
Gen-1 built dunes bike --SOLD--
'05 klx110 --SOLD--
'95 pw80
