Synthetic oil vs. conventional

[Maddoxsdaddy]

I'm the proud new owner of a 1994 18' Astro fish and ski with a Mercury 115hp of the same year. The motor is oil injected. The previous owner said he used quicksilver synthetic oil but i have a funny feeling he didn't know what he was using (he was a first time boater). My question is this... If he was using conventional oil, would it be a problem to dumping synthetic in the oil tank or would there be compatability issues. There is about half a gallon of whatever oil he used left in the tank and i don't want to run the tank too low before re-filling.
Thanks,
TB

 

[Silvertip]

Re: Synthetic oil vs. conventional

No -- synthetic, semi synthetic and conventional oil can be mixed. But since there is so little in the resevoir, why not drain it and start with what you want to use.

 

[Maddoxsdaddy]

Re: Synthetic oil vs. conventional

Good.... thanks.
Now to figure out the trolling motor battery charging system.....