I have 1995 Johnson outboard 50hp with the oil resivour that mixes with the gas automaticlly.  I just had the motor redone with a new power block and now I think I would like to unhook this and do my own gas oil mix rather than trusting the auto mix. Is this a good idea and if so how do you do this?  

Thank for the help

Before you do anything you should check with your local dealer and see if it can be done that way. I'm sure it would but just to be on the safe side!!!!!

Harry

With the technological advancements that have been made over the last 20 years, oil injection technology is proven. There's an alarm built into your system (usually in your throttle control box) that will trigger if/when the injector is not sending oil to the motor. I think there is more chance for incorrect fuel mixtures when you do it by hand - unless you accurately pre-mix it before adding it to the fuel tank. Many people gas up, then add what they think is the correct amount of oil and over time the gas/oil mixture becomes way too rich or way to lean. Bottom line - trust the injection technology! But that's just my opinion.....

I'll tell you what I was told but have not done yet. 
I have a '95 70hp Johnson on my Pro V Lund that I've had since new. The one repair shop I use told me to disconnect the oil injection and premix my fuel. Apparently the little pump on these units operate on a spring the size found in a ball point pen and will eventually fail and destroy the motor.

In my case trying to premix for a 32 gal on board tank did not make sense to me, so I've stayed connected. Also eventually I would like to re-power  my boat and whats the best way to get a new motor than to say "it's broke"! Now I know we're talking big bucks for a new one, but I can deal w/that.

If you not dealing with a large fuel tank like I am.... say the standard 6 gal..... I might do it.   But these are questions you should be putting to you dealer/repair shop, not to us. Listen to what they tell you and make the decision based on their recommendation.