Gas in the oil!

[joshua]

So after many attempts at fixing my carbs, I finally got them working. I knew they were leaking gas for a while, so I figured I better change the oil. It had only been in there for less than 5 miles, but it came out filthy black and of course it reeked of gas. What do I need to do when putting new oil in to make sure all of the poisonous gas is out of my crank case?

[Snow]

Well, you could put in cheap dino juice, run it till it warms up with no load (read: on center stand), then change the oil and filter once again. Just my humble opinion.

[joshua]

How much as to be left in to cause damage? And what sort of damage are we talking about? Thanks for the tips as well.

[Snow]

Honestly, I don't think there'd be enough to worry about after changing the oil and filter, running her on centerstand for a few minutes (gotta get her warm), and then changing the oil and filter again.

The main concern is gas in the main and rod bearings - it's a *horrible* lubricant and can cause those bearings to fail *very* quickly. That's why you need to run it on fresh oil/filter - to displace/dilute and gas that may have gotten in the bearings...and that's also why you don't want any load on her - if there is gas in the bearings, load could cause the bearings to fail....bearing failure sucks...trust me...seriously...I'll take some more picture when I resplit my '79's cases this weekend to replace my mains again (long story).

[79XS11F]

The gas in the oil likely helped wash everything better then normal. The lighter the oil the better it seems to clean stuff. Just try spraying WD40 on any dirty surface and watch the crap flow off the surface of the item. In any case all oil will come out black. oil contains detergents and chemicals to help keep particles in suspenion for the filter to trap. As suggested run some cheap stuff through it to rid the system of ALL gas and then return to what ever is your chosen brand. Don't worry about the oil coming out black just change it as per the manual specs and worry only if it smells BURNT when doing a change. That would be an issue in need of attention.
Rob