Page 1 of 1

2003 KDX200 losing coolant

Posted: 09:01 pm Oct 07 2017
by KDX Rippa #36
Hey guys so a few months ago I rebuilt the top end in my 03 kdx200 I broke the bike in and went on a couple trail rides no problem... During the first race with the new top end I was going up a hill climb, at the top I went to shift into 2nd and accidentally hit neutral. When I opened the throttle it suddenly started bogging out at full RPM, ever since then it bogs out at any random time when the bike is at full throttle its not all the time its only on occasion. then I noticed it was loosing coolant, fast forward to now I have to add about 2-4oz of coolant every time I finish riding. its becoming a pain in the ass not because I have to keep buying more coolant and I am always worried that its going to overheat if it loses to much. It doesn't smell like its burning it but I have no idea. could it be the head torque, blown head gasket, I have no idea I was also thinking it could be leaking out of the overflow tube but I have no way of finding that out. any ideas on what it could be?

Re: 2003 KDX200 losing coolant

Posted: 10:49 pm Oct 07 2017
by KDXGarage
Do you have the overflow tank?

2003 KDX200 losing coolant

Posted: 10:59 pm Oct 07 2017
by raygun
Maybe unrelated but I did have to change seal behind the water pump on mine. Check the weep hole perhaps?

2003 KDX200 losing coolant

Posted: 06:24 am Oct 08 2017
by ohgood
KDX Rippa #36 wrote:Hey guys so a few months ago I rebuilt the top end in my 03 kdx200 I broke the bike in and went on a couple trail rides no problem... During the first race with the new top end I was going up a hill climb, at the top I went to shift into 2nd and accidentally hit neutral. When I opened the throttle it suddenly started bogging out at full RPM, ever since then it bogs out at any random time when the bike is at full throttle its not all the time its only on occasion. then I noticed it was loosing coolant, fast forward to now I have to add about 2-4oz of coolant every time I finish riding. its becoming a pain in the ass not because I have to keep buying more coolant and I am always worried that its going to overheat if it loses to much. It doesn't smell like its burning it but I have no idea. could it be the head torque, blown head gasket, I have no idea I was also thinking it could be leaking out of the overflow tube but I have no way of finding that out. any ideas on what it could be?

pull the head and replace the head gasket.

Re: 2003 KDX200 losing coolant

Posted: 09:27 pm Oct 08 2017
by KDX Rippa #36
Jason wrote:Do you have the overflow tank?
yes I do I fill that with coolant and it drops to the low mark after 30 mins of ride time

2003 KDX200 losing coolant

Posted: 09:28 pm Oct 08 2017
by KDX Rippa #36
raygun wrote:Maybe unrelated but I did have to change seal behind the water pump on mine. Check the weep hole perhaps?
not sure about that there is no oil mixing with coolant anywhere so I don't really know

Re: 2003 KDX200 losing coolant

Posted: 09:32 pm Oct 08 2017
by KDX Rippa #36
UPDATE: I pulled the spark plug out today and noticed it had water drops on it so I pulled the head and sure enough the piston had drops of coolant on it and the cylinder wall was also drenched in coolant, I dried all the coolant in the cylinder and coated the inside with WD-40 to prevent rust while I am waiting for a new head gasket.

Re: 2003 KDX200 losing coolant

Posted: 10:52 pm Oct 08 2017
by KDXGarage
Did you install a new head gasket during the previous repairs?

Did you use a torque wrench?

Re: 2003 KDX200 losing coolant

Posted: 07:56 pm Oct 09 2017
by KDX Rippa #36
Jason wrote:Did you install a new head gasket during the previous repairs?

Did you use a torque wrench?
yea I replaced the gasket when I did the top end and I toured the head with a torque wrench. I took a look at the head gasket today and it looks a little messed up so I am going to replace it and go from there.

Re: 2003 KDX200 losing coolant

Posted: 09:17 pm Oct 09 2017
by KDXGarage
That is good. Eliminating vriables