Milky oil in 82 Honda CB450SC NightHawk?

Would gas blowing by the rings in the cyclinder cause the oil to look like coffee with lots of creamer in it? I know the motor is not water cooled so it’s not water and it smells kinda like gas. The one cylinder has only 30psi for compression (and the previous owner said the motor was good). Anyway trying to figure out if this would be the cause of it or not and what is the best way to flush the motor with out tearing it all the way down. Belive it or not the motor did start and idle like this (on one cyclinder). There was no noise or unsual sounds that would lead me to belive there was any kinda of bad wear (metal on metal) because of loss of oil or reduction in lubercation. Already know I will need to replace the cylinders or have the ones I have bored out. Just not sure if I will need to replace the bearings on the crank and what not. What is your take on it?

The biggest indicator that gas is in your oil is the oil will smell like gas. Since you indicate it does, flush it out.

It is very likely that your dead cylinder is the source of the problem. With only 30psi you are getting tremendous blowby which will put fuel into the cases.

Gas in the oil won’t kill your crank bearings overnight. I would just open up the top end, see what it needs, hone the cylinders, put in new rings, and ride happy. I doubt you did any serious damage to the lower end.

Just flush the oil a couple times, and don’t be running it with a toasted cylinder. Nothing good will come of it!

Note from a Reader:
This used to happen in my ’62 VW at the oil filler cap.  Never figured out the reason other than moisture probably being sucked in there.


Evan Fell

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