[hyperAKtiv1]

I have a k6 750 and am having major problem. I noticed today a sludge coming out my radiator and overflow tank. I stopped, let the bike cool off. Took the cap off and put distilled water n it and drove home. It wasn’t smoking and will still start fine. I got home and took both hoses off left side of bike to the water pump. It was sludgy af too. I hosed it out real Gud but I’m scared to try fixing something when I’m not sure what need fixing. It started w cracked stator cover. I patched it and it rode fine for one day til the case got here. Ran fine when I parked it. Got up n went down street and all this happened at once. What is my problem and where do I start to fix it? All inquiries n comments helpful.

 

[SparkyMJ]

I would suggest that this is a relatively involved repair, and premise my recommendation with this: If you aren't comfortable using (or you don't/won't have) a shop manual, all the standard wrenches and tools needed, or remembering and paying attention to all the details involved in engine repairs, I wouldn't attempt this repair yourself. But by all means, if you want to learn, do it!

Sludge in your cooling system is most likely oil in your coolant system. The key places where oil and coolant interface and are close together in the engine is:

• water pump
• oil cooler
• head gasket/cylinder head

I would say the stator cover damage is likely unrelated, but definitely something to investigate. I think on the K6 the stator is nearby the water pump but I might be wrong. Take it off and check things out. The stator cover isn't something to just patch up, the cover itself has the stator bolted to it. If the cover is damaged or cracked enough, the stator inside won't be sitting in the right position. Definitely replace or upgrade to a Woodcraft cover.

So I would start by draining the oil and coolant, and checking the fluids for weird colors, textures, debris, smells, etc. Check if the oil is milky or frothy, and see what the coolant looks like. Then I would check the water pump for dripping from the "weep hole". Common practice, google that inspection if you are not sure how to do it. That would tell you if your mechanical seal in the water pump is potentially leaking, and help you narrow down your issue.

The oil cooler is super unlikely to leak like this, since it's solid state and has no moving parts. But worth taking a look at.

Head gasket is the worst thing on the list for sure to have an issue with. I would resort to this last. If you know the water pump, hoses, and oil cooler are good, then that's the only remaining likely problem area. Look around your engine for signs of leaking of any fluids. And if you are equipped, take the cylinder head off and check it out.

Hope this helps, if this is too much, then I would just bring it to a shop.

-Mike

 

[BillV]

+1 The water pump has two seals, one for coolant and another for oil, with a weep hole between them. This makes it hard for one fluid to get to the other side. The oil cooler could fail by corrosion, freezing, or something hitting it. The first two would be associated with improper coolant. But the radiator would probably fail first if so and I'd expect you to know if it was the third. I'm guessing a leaking head gasket. You could drain the coolant and put a leakdown tester on the radiator. Sometimes you can hear the leak at the oil fill hole but it should leak down quickly if it's that big.

Any indication of coolant in the oil?

 

[TwistedMister]

yup, flush that cooling system, runa cleaner and go form there.. keep an eye on it, look for water droplets on oil filler cap and oil residue foam on radiator cap, underside of course..

flushing and cleaning is imperative in any event, whether it needs a head gasket, water pump whatever.. sounds like it got funky, then if it needs a head gasket whatever its less cleaning to do at that time, all that gunk can clog water passages, not good, get on top of it, yo can buy flush cleaners at auto part stores.. maybe just run water or partial coolant after flushing to see whats what, if its all good go back to 50/50..

if it comes back then you need to troubleshoot, get back to us

 

[hyperAKtiv1]

yup, flush that cooling system, runa cleaner and go form there.. keep an eye on it, look for water droplets on oil filler cap and oil residue foam on radiator cap, underside of course..

flushing and cleaning is imperative in any event, whether it needs a head gasket, water pump whatever.. sounds like it got funky, then if it needs a head gasket whatever its less cleaning to do at that time, all that gunk can clog water passages, not good, get on top of it, yo can buy flush cleaners at auto part stores.. maybe just run water or partial coolant after flushing to see whats what, if its all good go back to 50/50..

if it comes back then you need to troubleshoot, get back to us

I changed the oil and filter, ran some radiator flush shit through the system and put sea foam n my gas tank to clean everything Gud. Started fine. Ran Gud for a few minutes. I was really getting on it to see if it would hold up because the way I ride it is aggressive. I rode some wheelies and all was ok. Turned it off. Came n got on it again. Rode home. Started sounding like it was sick. Started overheating again. Got home and cooked it off. There’s oil in the pan but not showing in the window now. I had plenty oil in it cause I put 3 full courts in it right before I left home. I didn’t even go 20 miles all together. I’m stuck at what else to do. Please help.

 

[hyperAKtiv1]

I changed the oil and filter, ran some radiator flush shit through the system and put sea foam n my gas tank to clean everything Gud. Started fine. Ran Gud for a few minutes. I was really getting on it to see if it would hold up because the way I ride it is aggressive. I rode some wheelies and all was ok. Turned it off. Came n got on it again. Rode home. Started sounding like it was sick. Started overheating again. Got home and cooked it off. There’s oil in the pan but not showing in the window now. I had plenty oil in it cause I put 3 full courts in it right before I left home. I didn’t even go 20 miles all together. I’m stuck at what else to do. Please help.

When I dump the oil out the oil pan it’s not sludgy. I don’t have water n my oil I have oil n my water

 

[TwistedMister]

welp as mentioned check your cooling system for evidence of oil contamination vice versa.. can't see 3 quarts disappearing into the cooling system but maybe it spit it out the exhaust? were you able to see the exhaust at all when getting on it?

at the very least inspect your oil, coolant, then perform a leak down/compression test