2005 CRF250R jetting

I have a 2005 CRF250R with a 175 main, clip on 4th, stock leak jet and fuel screw is 1 3/4 out. It was a pain to start. once i get it started it runs fine but overheats sometimes. We took the Carb off last night and re checked everything. Valves are in spec. We think it could possibly be a head gasket leak. any ideas?

Over heats on the MX track or woods riding? How do you know it is overheating, egnine sieze/power loss?

MX and the weep hole is pouring water out once she gets warmed up.

That weeping means the water pump seal is going. You may be able to just replace the seal and be happy, if you are lucky.

It shouldnt be the seal. I just replaced the whole water pump. Seal included. It only has two rides on it since it started blowing water. Thats why we think its a head gasket leak. the head is leaking pressure into the water system. Then builds to much and blows the water pump seal.

Way before it would push coolant out of the water pump, it would blow through the radiator cap and into the over flow. The cap would have to be stuck shut and not be able to vent if the cap were at issue.Something is wrong with the water pump, either it is defective or a mistake was made on install.

Also, if it were the head gasket, it would stream out of the water pump, draining all the coolant pretty quick.

ok that makes sense. but this is the second time its happened. thats why we replaced the water pump system in the first place. so i agree with what you say but something is causing it to blow water pump seals. we now think either head gasket or warped head.

and you said it would stream out of the water pump. are you meaning on the bottom of the water pump cover where it seals?

Don't take it the wrong way, but you fixed it twice and it is still broken. Something you are doing is incorrect.

and you said it would stream out of the water pump. are you meaning on the bottom of the water pump cover where it seals?

Yes, it would squirt, to some extent, in pulse with the engine. But unless the radiator cap was frozen closed, it would vent out the overflow line first. Caps are made to withstand about 16 lbs of pressure. Seals, well over 90 lbs of pressure.

Hmmm ok well i have already ordered a new head gasket and were going to check and see if possibly the head or cylinder is warped. and the radiator cap isnt stuck. everything looks good and we just put another water pump seal on it with a certified mechanic watching over as i did it and it still does it. any other suggestions? i appreciate everything.

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