ZXR overheating/steaming

[Arctic_]

Hey, My kawasaki zxr400 is over heating after a little ride, i pulled up to the lights and its was steaming from under the fuel tank and i was like what the #$%^ so i dont know what the problem is, i then fill the radiator back up and then like 10 - 20 minutes later it did the same thing. i checked up the bike and there was water leaking but i dont know where from and it also release a pressure valve or something it went pshhhhhhhhhhhh

any ideas ??

[Switch]

Might have a block in the cooling system somewhere. Check all the hoses and things, try find a leak.
Does it have enough oil in it?

[Arctic_]

ok ill try that but if it was blocked why would it be using all the water in the radiator tank and then me refilling it back up again, its leaking somewhere under the bike

[SVboy]

If a head gasket is leaking,it could pressurise the cooling system-hence the pressure on release of the rad cap, or that could be a symptom of the overheating. Any water in the motors oil? Could also be a faulty thermostat,faulty rad cap, or leaking rad hose.

[sefer]

It could also be a faulty water pump, my 250 blocked very easily at one point with a bit of crap, the pressure built up once hot and burst the pump seal (rad cap pressure release failed).

[Bonez]

Catch tank pipes may be blocked.

[koba]

The water could be from a leak in the cooling system but is most likley coming from the overflow tank. The radiator cap itself is the "pressure relief valve" it vents into a tank that may be overfilled which then has an overflow drain hose off that where your water may be coming from. the tank will have a high and low water mark on it, fill it between those, check all the hoses for obvious signs of damage or leakage and refill the tank, then refill the radiator.

It is also not a case of just "topping up" the radiator, you need to make sure you get all af the air out of the system. fill it up then flick it of its stand and give it a shake if the level in the radiator caps hole goes down put more in. gently massage the hoses and if more air bubbles up put more water in. you may even have to start the bike with the radiator cap off and give it a bit of a slow run and see if the water level drops, if it does put some more water in.

After you know there is only water/coolant in there run it with the cap off and give it a rev, if it looks like there are lotsa little bubbles start crying coz you prob have a blown head gasket.

Was it all sweet and then suddenly started doing this or has it been recently touched? have you just got it?
Thinking of things like that may help you diagnose the problem easier. There arequite a few thing that could be leading to your problems but a faulty radiator cap, (or the sealing surface it seats on) a leak somewhere, incorrect filling, incorrect mix of coolant/water and blown head gasket are the most likley.
Also check the oil, if it looks milky it has water in it which can be from a blown head gasket.
The thermostat could be dodgy, you can test it in boiling water, just ask for more info if you get that far.
Also if it the coolant has lacked corrosion inhibitors you may have corrosion problems, it should be nice and rust fre untder the radiator cap, brown water is bad!
Could be the waterpump not working right for a multitude of reasons.

Don't be overwhelmed! It ain't all that hard so if you have reasonable mechanical understanding it is worth having a play trying to find what is wrong with it, It could cost a bit from a shop.
Just take your time, label things and write notes if you have a memory anything like mine! dont overtighten nuts and bolts either...

A workshop manual will save you alot of time/effort if you decide to work on it yourself.

[koba]

http://auto.howstuffworks.com/cooling-system.htm
Some basic info, it is kinda crap but im sure you can google better stuff out there.

[MaxB]

Koba is onto it. You have plenty to check out. The only thing I can add is 'does the fan cut in when it should?' As the engine gets hot the fan should cut in and drop the temp even in heavy traffic. When it is not working the temp will rise and rise and water can spew out of the catch tank.

The fan sensor/sender unit is usually embedded in a corner of the rad. Also check the fan blades 'cos when they get hot Kwak blades can warp or melt.

Just come back to the list if you get stuck. Good Luck.

[Arctic_]

Hey thanks for the great feedback.

Ive taking off the fairings and fuel tank, its looks like it leaking from the pipe the comes from the top of radiator to the engine if i look in there i see like a little river of fluid running down the motor to the ground. that area is just under the carbs area if im correct.

and the release pressure aint coming from the radiator cap its coming from near the motor under the fuel tank area.

And the water was pretty brown but i gave it a flush and now its clear. so tomorrow im going to check further and see if i can see if its just a stuffed gasket or a crack

[Sparky Bills]

Remember also, that Water has a lower boiling point than antifreeze. So make sure there isnt just water in there. You MUST mix it with the proper coolant.
The bike is more likely to boil over if you only have water in there.

[sefer]

The fact the 'water' was brown probably means that it is in fact water and not coolant in there, and you've got a bit of rust happing in there.

Not a big deal, but do make sure you flush it well and check out your thermostat and cap, as rust can fuse both closed, meaning the water can't circulate (thermostat) the way it should and it will create a huge amount of pressure on one side of the system which could pop a hose or seal if the rad cap valve is sticking (even if it's partially working).

Water is ok for testing it all out, and because it heats up faster will probably make testing easier, but once your sorted use some coolant with a rust inhibitor.

[Arctic_]

yeah i was just testing it with water to see where the leak was coming from, im hoping its coming from a loose bolt or broken gasket, i can see were the water is leaking from but it tucked under nicely

[Arctic_]

Hey all,

Found out why it was overheating, the top radiator pipe had a split in it near motor heat which was leaking fluid really fast on to the motor causing it to steam when the water hit the motor, but all is fixed now and im glad it was only that.

Once again thanks for the great feedback

[Arctic_]

Hey,

Ok got top hose fixed and now the bottom hose split and now i need a new waterpump cause the waterpump seal has stuffed it self and now there water in the oil and cream white stuff. (not a good sign)

any one know where to find part i need? and how much