Kx over heating?

[Kx_rider]

my kx is getting real hot.. im pretty sure it shouldnt be.. i have ant-freeze in (green) and the fins are too beat up, but it gets hot and i remove he rad cap and some stem gets out..What could be going on here?? thanks guys

 

[Kx_rider]

Anyone?

 

[CR500pilot]

Impellar could be shot, rad cap, jetting. A few more details would help. KX what? Does it do it all the time or just after hard riding. A little bit of steam is not necessarily bad. You say your rad is beat up, is it bad enough to not let any air pass through? Check the impellar, may want to replace the cap, after time the cap won't hold the pressure it should. How is your jetting, may want to go up a size on the main jet. Did you do any work to it recently? I'd start and inspect all the cooling system components and then the jetting. Don't do everything at once.

 

[Filthy_McNasty]

Why do you think it's getting too hot? What sort of symptoms does it have?

i remove he rad cap and some stem gets out..

Of course steam comes out if you remove the radiator cap when the engine is still hot. Hell, you're lucky not to get scalded with spewing boiling coolant. Removing the cap from a hot radiator is a very bad idea... :yikes:

 

[Kx_rider]

Why do you think it's getting too hot? What sort of symptoms does it have?

Of course steam comes out if you remove the radiator cap when the engine is still hot. Hell, you're lucky not to get scalded with spewing boiling coolant. Removing the cap from a hot radiator is a very bad idea... :yikes:

there is no pressure to spit out at me.. and I push down incase and i turn real slow so the little bit of pressure in there gos out, i already know u shouldn't open when hot but i was just checking stuff. Also no symptoms runs the same as hot when cold but im worried im gonna frie my new piston

 

[Kx_rider]

Impellar could be shot, rad cap, jetting. A few more details would help. KX what? Does it do it all the time or just after hard riding. A little bit of steam is not necessarily bad. You say your rad is beat up, is it bad enough to not let any air pass through? Check the impellar, may want to replace the cap, after time the cap won't hold the pressure it should. How is your jetting, may want to go up a size on the main jet. Did you do any work to it recently? I'd start and inspect all the cooling system components and then the jetting. Don't do everything at once.

86 Kx80



dont know what a impeller is.. haven't touched the jetting its all the same like it was when i got it last year.. and i dont remeber it ever getting this hot.. the rads not too bad enough air should be getting throw it. i did do work to it recently rebuild the top end, i wouldn't know what to look for to inspect the cooling system but id like to learn..This is the first bike iv ever owned and i haven't been around bikes at all, so im all new to it..

 

[Filthy_McNasty]

there is no pressure to spit out at me.. and I push down incase and i turn real slow so the little bit of pressure in there gos out, i already know u shouldn't open when hot but i was just checking stuff. Also no symptoms runs the same as hot when cold but im worried im gonna frie my new piston

If there's no pressure in the cooling system, you have a leak, most likely a bad cap. That would also explain the running hot. Replace the cap, they are only a few dollars. If nothing changes, have it pressure ested.

 

[CR500pilot]

If the problem didn't start until after the rebuild, I would suspect that you have air trapped in the cooling system when you refilled it. There should be a drain screw on the water pump cover. Take it out and check for fluid. If you can't find that, loosen one of the hoses connected to the cylinder head. Also you should mix 50-50 anti-freeze and water. The impellar is under the cover where the hose goes from the engine to the radiator. You should buy a manual for the bike, they're not that much and you will be able to familiarize yourself with the bike. You may also check to see if one of the hoses were kinked when reconnected. The cooling system is: the radiator(s), the hoses that connect them to the engine, the water pump (impellar) and the coolant. A manual will be a lot cheaper than another top end.

 

[keip82]

it sounds like the cap.

 

[Kx_rider]

If the problem didn't start until after the rebuild, I would suspect that you have air trapped in the cooling system when you refilled it. There should be a drain screw on the water pump cover. Take it out and check for fluid. If you can't find that, loosen one of the hoses connected to the cylinder head. Also you should mix 50-50 anti-freeze and water. The impellar is under the cover where the hose goes from the engine to the radiator. You should buy a manual for the bike, they're not that much and you will be able to familiarize yourself with the bike. You may also check to see if one of the hoses were kinked when reconnected. The cooling system is: the radiator(s), the hoses that connect them to the engine, the water pump (impellar) and the coolant. A manual will be a lot cheaper than another top end.

ok So loosen the screw with the Ant-freeze in? its already 50-50

 

[Kx_rider]

Ttt

 

[CR500pilot]

KX rider - just try this. With the cap removed tilt the bike side to side and top it off again. Start it with the cap off and let it run for a few minutes, then cap it let it warm up and shut it down. After it cools check it and top it off again, and I think you'll be able to rule out air in the system. You never did answer what you did to it or inspect the cooling hoses.

 

[griffbones]

There is a bleed screw on top of the cylinder head that should be cracked open until antifreeze comes out. Open this screw up until the air is out and then close it, this should help if the problem is air in the system. BTW do this proceedure with the engine shut off, then do as stated above, run the bike at idle with the cap off until most of the air bubbles are gone, then shut off the bike and let it cool, then top off the radiator and reinstall the cap, then you should be good to go.
If this doesn't solve the problem then you may have a bad cap, not holding pressure.

 

[Kx_rider]

You never did answer what you did to it or inspect the cooling hoses.

I rebuilt the top-end thats it and i used a small screw driver to open up some close/bent fins on the rad.(no i didnt poke any holes in) thats all i did other then add new coolent and motor oil after the rebuild..im going to do as u guys say and plus a new cap. Thanks

 

[CR500pilot]

I rebuilt the top-end thats it and i used a small screw driver to open up some close/bent fins on the rad.(no i didnt poke any holes in) thats all i did other then add new coolent and motor oil after the rebuild..im going to do as u guys say and plus a new cap. Thanks

Let us know how it goes. The rad should be OK if you weren't having a problem before.

 

[Kx_rider]

UPDATE: ok today i pulled the water pump cover off and found that 2 fins on the impaller have chucks missing off them.. now im wouding... where did thos chunks go... maybe there in the coolant system some where... i chck houses not in there.. either the rad.. or in the top end chambers.. or maybe it was like that when i bought it and the owners before have already removed the missing chunks

 

[griffbones]

How do the water pump bearings feel? Something had to of caused this to happen!

 

[CR500pilot]

The impellar is corroded and the chunks probably broke off after weakening. I'd try to flush everything out. Also as mentioned above check the bearing on the water pump (impellar) shaft.

 

[Kx_rider]

Bears are tight no play at all

 

[Kx_rider]

Should I replace impeller?



http://i147.photobucket.com/albums/r298/eddiem1920/Picture034.jpg


See the picture ^

 

[IndyMX]

Yes, replace the impeller before it ruins the bearings and seals..

Might want to consider washing that thing from time to time too...

 

[griffbones]

You don't clean the bike up before you open up it's cavities?
I don't know about the older KX's but the newer models have a stamped steel impellar, that looks like an after market unit made of cast. And it doesn't look to me like corrosion did that, it looks like it hit something and broke, but either way I would replace it!

 

[IndyMX]

Yeah, I'd thing that corrosion or cavitation would cause all the blades to wear, not just 2... and not so violently...