Mayday Mayday, Need Your Help

11 replies to this topic
  • CanRider

Posted June 30, 2005 - 09:04 AM


Hows it going everyone?

Here is the scoop. Just recently bought a 2000 yz426f. Awesome bike, no troubles starting, has been a great ride.
Well it starts now, last night, I went for a good ride, I stopped the bike for about 10 mins or so, to ride a friends ATV. When I started the bike back up, a had a large dump of Engine coolant.

Now I am not a whiz with bikes, but I am also not stupid. The first thing I did was shut the bike off. and reached for the oil dipstick. I opened it up, and was relieved it wasn't white or cloudy, meaning there wasnt an internal leak. The oil didnt smell burnt, another good sign....after letting the bike completely cool, I removed the rad cap, it was obviously lowered, if it was empty I could not tell. Now I am on a military base, and its difficult for me to find the space to rip this bike apart, I didnt notice any tubing, or pipes that were loose, or missing...
Any ideas real quickly as to what I might start with, so that way I can effectively get right to the problem and find out.

  • wrkaholic

Posted June 30, 2005 - 09:27 AM


It might not be a problem.

1. The YZ426 does not have an overflow bottle, so, if it gets hot, it will spit out coolant.

2. It may have more water than coolant, thus, contributing to the overflow
3. Your radiator cap may be tired and not holding the pressure it was designed for.

4. If you were riding very technical low speed trails with no airflow, it will contribute to the overhot condition.

1. Get a new cap.
2. Fill radiator with good quality coolant. They have some stuff at the dirt bike stores that is supposed to handle the heat better. I forgot the names. I think it maybe called ICE.
3. Make sure your oil is at the proper level.
4. Go out and ride in 2nd and 3rd gear, a speed with good airflow over the radiator, stop and see if it is still overheating. If not, you maybe OK. :)

  • MotoGoalie

Posted June 30, 2005 - 10:08 AM


They spew some coolant. It's normal as they run really hot.

  • PumpkinHumper

Posted June 30, 2005 - 11:15 AM


Were did it spit the coolant out from? The radiator over flow tube connected to the radiator cap or from the bottom of the water pump? If its the water pump you have a bad seal / shaft. If its the radiator line it may be a week cap.

  • CanRider

Posted June 30, 2005 - 11:55 AM


It came directly from underneath. it spilled onto the skidplate, and over the side. Again, I am sorry guys, my bike is stored at a location opposite to where I live, so I can't check this stuff now, this is much appreciated, from a busy soldier.
I cant say that it all spilled out, but it was an amount enough to warrant me to shut-er-down for the night. there was no coolant that I could visibly see in the rad, so there was enough spilled out to drop the level at least 2-3 inches. It was scary.
Thanks for tips guys, I was already out today looking for engine ice. It looks like I might have to order it online, being in canada, we have to have that sorta thing shipped on the backs of polar bears, or with dogsleds.

  • PumpkinHumper

Posted June 30, 2005 - 12:48 PM


Did it come from the front of the motor onto the skidplate or the rh side of the motor onto the skidplate? The front is were the radiator drain hose usualy is. The rh side is were the water pump is at.

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  • CHEEZE13

Posted June 30, 2005 - 06:09 PM


Probably just boiled over and spewed out the overflow hose, flush it change the fluid put some water wetter or something like that with distilled water replace the cap with a new one see what happens.

  • sirthumpalot

Posted June 30, 2005 - 07:07 PM


That's a bunch. Did it idle for a long time before it spewed? Here are my thoughts:

1) Blew a water pump seal. The coolant would have come from the right front of the motor, possibly dribbled onto the skid plate but more likely strait shot down from the pump. Relatively easy fix

2) It idled too long and boiled. How long did it idle or run in neutral for?

3) Maybe you did blow a head gasget? Odd that it would happen at idle unless it got very very hot.

Other than that I'm out of ideas. Let us know what you find, and thank you very much for your service!! :) :)

  • CanRider

Posted July 03, 2005 - 06:02 PM


Good news, to anyone still interested. I filled the rad with water, to see if I could find a leak. I applied pressure, and nothing!!!! GREAT NEWS!!! means all is well. I have ordered the parts for an oil change, and that will be done asap. Thank you everyone for your help!!!

  • Satch0922

Posted July 04, 2005 - 04:35 AM


Good news, to anyone still interested. I filled the rad with water, to see if I could find a leak. I applied pressure, and nothing!!!! GREAT NEWS!!! means all is well. I have ordered the parts for an oil change, and that will be done asap. Thank you everyone for your help!!!

There are many opinions on what type of coolant to use. I used Engine Ice in my 426 and never had it boil over or puke. Good stuff.

  • mayday

Posted July 04, 2005 - 08:16 AM


Was someone calling?????

  • MisterMan

Posted July 04, 2005 - 11:41 AM


Was someone calling?????

:) hahahah lololol :)

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