water pump?
- Thread starter nhrider
- Start date
GMP
Active member
The screw is an M6 RH thread and is threaded through the impellar(brass insert), then into the end of the pump shaft. It should also be loctited. If its not a new bike, I would take the side cover off and hold the shaft from the back. This way there will be no stress on the plastic gear if you need to apply a lot of force. My '00 and '07 came loose easy and '03 was a bitch. Better safe than sorry and all it costs is a side cover gasket. While your in there change to the LTR alloy impeller. Check the parts manual for reference dwgs.
nhrider
Silver Level Site Supporter
Done!
The screw and impeller came off as one. Not sure if that was the correct way but it took hardly any pressure to get it off. My screw was M5 not the M6 and already had the alloy impeller.
Now I need to run some ATF through it to clean out the coolant/water. I already ran the bike once and changed the oil and it was still kind of milky with a grayish in color swirl. I'm "working" from home tomorrow so hopefully I can get this cleaned up and go riding this weekend.
Thanks for the help GMP! You're the man!
The screw and impeller came off as one. Not sure if that was the correct way but it took hardly any pressure to get it off. My screw was M5 not the M6 and already had the alloy impeller.
Now I need to run some ATF through it to clean out the coolant/water. I already ran the bike once and changed the oil and it was still kind of milky with a grayish in color swirl. I'm "working" from home tomorrow so hopefully I can get this cleaned up and go riding this weekend.
Thanks for the help GMP! You're the man!
GMP
Active member
Yes, impeller and bolt come off together and I pulled a typo, it is an M5.
Water pump seal leaks are very rare on these bikes. The seal is a multi part ceramic/graphite high speed pump seal common in industry but not in the MC world. The shaft does not turn in the seal and it hardly ever wears out.
The reason I'm saying this is because its more common to get water in the oil from the trans/PV vent that drops between the frame and right rad. Any water crossings lately? Happened to me a couple times on my first '00 GG until I routed the vent into the airbox. If you have an '05+ with the tank vent nipple in the frame, use that for the trans vent, and a shorty cap vent line for the gas cap. Clean solution.
Water pump seal leaks are very rare on these bikes. The seal is a multi part ceramic/graphite high speed pump seal common in industry but not in the MC world. The shaft does not turn in the seal and it hardly ever wears out.
The reason I'm saying this is because its more common to get water in the oil from the trans/PV vent that drops between the frame and right rad. Any water crossings lately? Happened to me a couple times on my first '00 GG until I routed the vent into the airbox. If you have an '05+ with the tank vent nipple in the frame, use that for the trans vent, and a shorty cap vent line for the gas cap. Clean solution.
nhrider
Silver Level Site Supporter
I did do a water crossing a couple of rides ago. It just had fresh oil and I change it every 2-3 rides but never thought about sucking up water. Hope I didn't cook her! I did search the forums and did come across the re-route of the trans/PV vent. I'll be doing that as well.
Thanks again!
Thanks again!
Gotta change my water pump seal
I ride in the sand a lot, at high RPM. Water crossings are rare for me.
I have a 2005 Gas gas EC 250.
I bought a LTR alloy impeller and a new cover gasket and shaft seal.
My trans/PV vent tube is already routed up tword the tripple clamp. It actualy comes out just below my headlight. People I ride with tell me that my headlight is smoking sometimes when a little trendle of exhaust drifts out of there.
I am gathering that I still need to remove the screw from the plastic impeller. Does it have reverse threads or anything funkey like that ?
Will the seal come out in one piece, or will I wind up mangling it to remove it ? What order will the three separate pieces of the seal go in, or are they to be assembled together and installed as a single unit ? Does anyone have a photo or two ? My GG manual has a drawing, but its in michro writing. Is there a larger print version somewhere ? Are there any additional tips on this procedure ?
I love my Gas gas !!!
I ride in the sand a lot, at high RPM. Water crossings are rare for me.
I have a 2005 Gas gas EC 250.
I bought a LTR alloy impeller and a new cover gasket and shaft seal.
My trans/PV vent tube is already routed up tword the tripple clamp. It actualy comes out just below my headlight. People I ride with tell me that my headlight is smoking sometimes when a little trendle of exhaust drifts out of there.
I am gathering that I still need to remove the screw from the plastic impeller. Does it have reverse threads or anything funkey like that ?
Will the seal come out in one piece, or will I wind up mangling it to remove it ? What order will the three separate pieces of the seal go in, or are they to be assembled together and installed as a single unit ? Does anyone have a photo or two ? My GG manual has a drawing, but its in michro writing. Is there a larger print version somewhere ? Are there any additional tips on this procedure ?
I love my Gas gas !!!
GMP
Active member
Impeller bolt threads are right hand M5, nothing strange.
The seal is very unique to an MC. Its in three parts. Consult page 10 of the '07 parts manual (same parts as '05). Pay close attention when taking things apart. Its actually eaiser and less damage prone than a normal seal. The part on the shaft is sealed with a tight fitting rubber cup (that doesn't move on the shaft), and has a spring loaded graphite ring. The other half has a ceramic ring and is pressed in the side cover over the bearing. The seal is accomplished by this graphite/ceramic interface that is very low friction and under spring tension. Also, when the system coolant pressure rises with temperature, the sealing force will rise as well. Nice design, no grooved shafts, and never wears out. I doubt your seal is bad, unless the bearing is bad and the shaft is not running true.
The seal is very unique to an MC. Its in three parts. Consult page 10 of the '07 parts manual (same parts as '05). Pay close attention when taking things apart. Its actually eaiser and less damage prone than a normal seal. The part on the shaft is sealed with a tight fitting rubber cup (that doesn't move on the shaft), and has a spring loaded graphite ring. The other half has a ceramic ring and is pressed in the side cover over the bearing. The seal is accomplished by this graphite/ceramic interface that is very low friction and under spring tension. Also, when the system coolant pressure rises with temperature, the sealing force will rise as well. Nice design, no grooved shafts, and never wears out. I doubt your seal is bad, unless the bearing is bad and the shaft is not running true.
Hmmmmm...
I removed the cover and impeller.
The seal did have some whitish oil on it.
After I changed the oil, I did go for a very short 5 or 6 min. ride and I noticed no change in the oil colour in the site glass.
When I drained the coolant, it was clear, with no oil contamination. The coolant level was just a tad low in the radiator when I checked it after draining all that milkey white oil.
Where can I get a good shop manual for an 05 GG EC 250 ? Would Gofasters have one ? I have the little one that I got with the bike, but its all in michro writing and not very detailed.
I dont even want to THINK about changing that bearing. Therre should be no reason for that bearing to be bad or the shaft to be bent. I have never ridden in such a manner as to cause any of those types of problems. Would the cases need to be split if I needed to change that bearing ?
I removed the cover and impeller.
The seal did have some whitish oil on it.
After I changed the oil, I did go for a very short 5 or 6 min. ride and I noticed no change in the oil colour in the site glass.
When I drained the coolant, it was clear, with no oil contamination. The coolant level was just a tad low in the radiator when I checked it after draining all that milkey white oil.
Where can I get a good shop manual for an 05 GG EC 250 ? Would Gofasters have one ? I have the little one that I got with the bike, but its all in michro writing and not very detailed.
I dont even want to THINK about changing that bearing. Therre should be no reason for that bearing to be bad or the shaft to be bent. I have never ridden in such a manner as to cause any of those types of problems. Would the cases need to be split if I needed to change that bearing ?
Last edited:
eff
Silver Level Site Supporter
GMP
Active member
Everything is contained in and replacable from the side cover. Pull the cover off the bike and take it to the bench. If there is coolant in the oil, its also possible that its from a gasket leak. Two coolant passages go right through the cases and side cover to the pump. Check the bolts. Its obvious how it works once you take it apart.
I think I will do the top end too.
It may just be the head gasket leaking. I ordered a new WP seal and I will install a new one (weather it needs one or not), and look at that bearing.
The bike probably could use a new top end. I run a ton of RPM in the sand. I have had the bike now for over a year and never changed top ends. I noticed that it was eating a lot (a lot) more gas than usual on my last ride. I bet the compression is lower too.
I noticed with two strokes that they seem to run dramaticaly better just before they 'let go'. GG is running better than ever and shes eating a full tank in just three hours of riding (it used to take twice that time in the same conditions). The break-in ride was a gas eater too.
Those top end O-rings will get swapped along with the top end.
It may just be the head gasket leaking. I ordered a new WP seal and I will install a new one (weather it needs one or not), and look at that bearing.
The bike probably could use a new top end. I run a ton of RPM in the sand. I have had the bike now for over a year and never changed top ends. I noticed that it was eating a lot (a lot) more gas than usual on my last ride. I bet the compression is lower too.
I noticed with two strokes that they seem to run dramaticaly better just before they 'let go'. GG is running better than ever and shes eating a full tank in just three hours of riding (it used to take twice that time in the same conditions). The break-in ride was a gas eater too.
Those top end O-rings will get swapped along with the top end.
whodat
Gold Level Site Supporter
I too have milky tranny fluid!(grayish) checked the coolant level and it was low so I am thinking water pump seal. I see people discuss the vent tube from the power valve as a culprit but I can't see how water entering the top-end can get into the bottom end unless there is a vent tube for the tranny.
Can anyone shed more light on the "ports" between the side and center case where coolant could leak. Is this just a matter of a gasket gone bad or is it more envolved than that? I know I have lots of questions but I just want to buy all the stuff needed and get this fixed the 1st time. Any advice would be great!
Can anyone shed more light on the "ports" between the side and center case where coolant could leak. Is this just a matter of a gasket gone bad or is it more envolved than that? I know I have lots of questions but I just want to buy all the stuff needed and get this fixed the 1st time. Any advice would be great!
HydroDog
Gold Level Site Supporter
The transmission vents up into the power valve chamber on the right hand side cover.
I had the same milky oil problem last month after a very wet ride. I never deep sixed the bike but just alot of standing water in the trail. I removed the seal and could not find any problem. My only concluesion was that water could be drawing in up the vent hose during the combustion cycle which is causing a vacuum on the vent hose. I have since installed a longer vent hose and rerouted up higher by the steering stem and have not had the problem since. The hard part was trying to get all the moisture out of the tranny. I flushed it out with kerosene and drained and refilled after 2 more rides before it became clean again.
