Gear oil colour?

Beginning to wish I listened to everyones advice about not buying a OMC Cobra powered boat
However, this is my latest problem,drained old gear oil out and was told it looked like it had small ammount of water mixed in with it(dark green/brown in colour, not "milky")
So refilled with new oil and ran motor up using muffs for about 20 mins at idle
Removed top cover plate to check all was OK, found new oil was the same colour as the old oil that was drained
If this is water ingress where could this have happened, would it be through the impeller drive shaft? or somewher else
I will post a picture tomorrow of old and new oil if I can work out how to upload them on to this site
As always, any help/advice much appreciated and welcomed
If any more info required please tell me

if not milky then it's fine.

Thanks for good news! but I will try and post pics later just for peace of mind

Also forgot to ask,is it OK to use normal automotive gear oil in this outdrive
I have a 5.7l engine with a 5.0l cobra outdrive(is this normal/OK because they dont match?)

I do. The cheapest stuff i can find it's all non foaming now a days's.

Great news on the oil, what about the engine/outdrive model nos, should i have a 5.7l outdrive to go with the 5.7l engine? this may sound like a ridiculous question but it isnt to me cos i dont know, thanks for your interest and patience

yes the gear ratio must be correct.

Do you mean that it is correct as it is now(5.7l engine/5.0l outdrive)

Or do you mean that it should be 5.7l engine/5.7l outdrive?

If it is wrong, what are the consequences by running it as it is

Thanks again

you will be ok with a 5.0 drive with a 5.7 motor. I think wot should be posted on your motor but if i remember correctly it is 4200-4600 rpm. Reason i state wot is you don;t want to over rev it.

So say you reach wot and you still have travel left in the throttle you may need to go up in pitch on the prop, lets worry about that after your first run on the water.

I'll look it up or if you want you can look it up in your manual.

Your memory isnt bad, the manual states 4200-4400rpm for WOT, we will be dropping her in the water Friday/Saturday, so will post results of sea trial then
Fingers crossed and thanks again