01 YZ426F loosing water??

I have an 01 YZ426F and every time I go to ride it I need to put coolant in it. Now it is coming out of the overflow hose by the cap. When I ride it, it is getting plenty of airflow through the radiator because I really don't ride it slow. Now when I come to a stop and turn it off it will start leaking water. Could this just be that I need to replace the cap or should I look at something else?

I'd replace the cap first.

I'd replace the cap first.

I was going to replace it with the HP cap and put some engine ice or water wetter in it witch ever it is for the radiator. Just didn't know if I should look at anything else wile I was at it.

Thanks I will start there.

I have an 01 YZ426F and every time I go to ride it I need to put coolant in it. Now it is coming out of the overflow hose by the cap. When I ride it, it is getting plenty of airflow through the radiator because I really don't ride it slow. Now when I come to a stop and turn it off it will start leaking water. Could this just be that I need to replace the cap or should I look at something else?

I had the same problem with the same bike. Had to re-top off after every ride, when my buddy with the same bike rode for approx. 30 hrs and never needed to top off.

I had new top end gaskets put on, and it solved the problem.

just my .2 cents.

do you look at the over flow line to see if it's spilling out?..like over heating?

do you look at the over flow line to see if it's spilling out?..like over heating?

When I am ridding it and stop to wait for someone or something like that it has a steady drip from the over flow line. Also when I stop and shut it off it will spill out of the over flow tube for a bit also.

I just got some water-wetter from Red line and am going to see if it helps.

ook..so you are over heating..do you ride in 1st/2nd a lot?..i didn't over heat until i rode a track for the first time and stayed in 1st/2nd..but when i ride trails i am staying in the high gears and don't over heat..

ook..so you are over heating..
You don't know that.

The first order of business is to test the cap to see if it will hold its rated pressure correctly. The stock cap is 1.1 Bar (16 psi), and should be adequate if healthy. Next you have to understand that the radiator cannot be filled to the top when cold without then loosing some as it heats up, regardless of what the manual says. The coolant level should remain steady at a point where it just covers the radiator tubes.

After that, you go looking for other problems, but not before.

You don't know that.

The first order of business is to test the cap to see if it will hold its rated pressure correctly. The stock cap is 1.1 Bar (16 psi), and should be adequate if healthy. Next you have to understand that the radiator cannot be filled to the top when cold without then loosing some as it heats up, regardless of what the manual says. The coolant level should remain steady at a point where it just covers the radiator tubes.

After that, you go looking for other problems, but not before.

oh ok

This is what I added to my bike to help with the same problem.

Paid $18 total for the mod.

I was going to use the coolant overflow tank that neokinetiks is talking about but I tried a couple of other things first which fixed the overheating on my '06 450. 80% distilled water (79 cents from walmart) and 20% propylene glycol ($11 per gallon from walmart, its called Low Tox by prestone) and a few capfuls of water wetter per gallon. I rode a few times since using this coolant mix and no overheating and that was before I put on the 1.6 bar radiator cap from pitposse.

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