what would be some harmful affects of there being oil in the coolant

 

The worst would be a blown engine.If there is oil in the coolant , there will be coolant in the oil.Engine bearings don't like water/coolant.They like oil.
Most probable cause is a bad head gasket.
Don't put it off , get it fixed.

 

you have a blown head gasket possibly both of them are blown

 

A few easy signs your head gasket is blown.......

1.) White smoke from tail pipe on start up
2.) Coolant in oil (or vise versa)
3.) Opening up the rad cap (upon stat up of a cold engine ONLY) and it looks like a hot tub.

My old 87 Shadow was notorious for bowing head gaskets......along with the odd piston failure too.

 

yes good to get that fixed soon, as the oil will eff the whole cooling system = big oily mess to clean out....

 

Kinda the other way around , coolant in the oil will destroy the engine bearings in short order.
A little oil in the cooling system won't really hurt anything.

 

well post #2 already said that so didn't need to repeat. i beg to differ.. oil in the cooling system makes a big time mess and you need to citrus/chem flush to get it out. guess it would depend on how much oil...

suffice to say not a good idea to run the engine like that.