Crankcase OIl

[rungrandpa]

When we were riding yesterday, my grandson mentioned he has to add oil to the crankcase every time he rides (he's riding my old 1990 KDX 200). No leaks. I told him it was probably burning the oil through the crank seal. His spark plug looks like that could be the case. Can it be anything else?

[Chuck78]

When we were riding yesterday, my grandson mentioned he has to add oil to the crankcase every time he rides (he's riding my old 1990 KDX 200). No leaks. I told him it was probably burning the oil through the crank seal. His spark plug looks like that could be the case. Can it be anything else?

If it's using gearbox oil, it's very likely to have a bad right side crank seal. I highly doubt you could get open oil bath gearbox oil leaking into the coolant system, it's always the other way around where you get coolant into the oil when the water pump seal or shaft leak. There's nowhere else where it would go besides burning it or leaking it out.

You can try power washing it and degreasing it, letting it dry off, and then covering the outside of the engine with some talc powder and taking it out for a ride in dry conditions. If it's leaking externally, you will see trails in the talc powder indicating where the oil came from. Without that, you usually end up just with a big oily mess and no real idea where it originated unless you get lucky. Try that as a last resort.

Best of luck!