4 cylinder, mercury 125, 2001 (single, gravity feed reservoir)

on this type system delete an go on mixing oil

How do you all feel about a 2013 Mercury 150 ProXS oil injection system? It's 5 years old and wondered if I should have it removed soon or wait a couple more years?

DFI motor is not going to be happy with premix. I don't know anyone who's attempted, but I'm sure the opinions will follow quickly.

Can`t be done on direct injection outboards. Without major changes. That carburated 125 Merc has the weakest oil injection system. Seen too many get the pistons. Those clear oil lines breaking. Get rid of the oil injection and pre-mix.

Sorry for dumb question but are you saying it should be removed because of the age and that it will start failing? Just curious because I have a 2002 125hp 2 stroke mercury that I recently bought.

I've always bypassed the VRO pumps on all my 2 smokers. Yes they do have alarms but once the alarms go off if they go off there is always that possibility that it's too late. If you mix it and don't use a paper fuel filter and there is no problems.

Ok, just so everyone is clear.
Carb and EFI two stroke motors lose nothing by premixing. Go ahead and do it, it'll keep peace of mind.

On the DFI motors, optimax, HPDI, Evinrudes take a complete different approach to how they get the oil mixed in the crank case, and should not be bypassed.

So I can premix in the gas tank and leave the oil in the outboard or do I have to disconnect something on the outboard if I premix in the gas tank? Any issue leaving premix in the tank over the winter. (Compared to leaving regular fuel)? Can I still put marine fuel additive in the gas tank if I premix?

Sorry for questions but trying to make sure I understand.

I ordered the block off kit. Should be here wed or thur of next week. Hardest part looks like it gonna be removing the lower cowling cover...
The boat has half a tank of fuel on the guage, I guess I'll be syphoning it out to measure gallons to premix accurately

Do the block off then, No need to go through emptying tank to measure gallons IF you know how many gallons it holds when full. Example:20 gallon tank, mix for 1/2 tank = 10 gallons. . Mix rich (add oil) for 12 gallons just to make sure. Better to mix slightly rich than too lean. Should be a plate on tank listing capacity OR google your boat specs , if it's an under seat hidden tank. OR once you find out how big tank is, add oil for full tank mix, THEN go top tank off. Pull line from motor & pump bulb into a gas can till you get premixed fuel to motor end. . Put line back on , pour fuel back into boat & go crank it up. Since you'll have a full tank, it's important to use that fuel before phase seperation 2-3 weeks sitting. PERFECT reason to tell wife that tank of fuel HAS to be USED in 2-3 weeks. Voila!!! Several trips quickly.. LOL.

PS: have fun.

Got everything pulled off for oil injection. I took Curt's advice, looked up the fuel tank specs and added it a smidge rich. Removed fuel line from engine and pumped bulb till it changed colors then reconnected. The block off plate should come in the mail Wednesday.

I guess I will play devil�s advocate here I have an older very well kept 1988 Skeeter SD80 with a Mariner 75hp and I have never unhooked the oil injection. I did have one oil leak about 10 years back and the mechanic replaced all oil lines and said I was lucky after doing a compression check. Granted I do not use this boat hard and it stays in the garage exept the half dozen or so times I can get away from work to fish.

I don�t plan to unhook it maybe someday I will wish I had but for now the old motor starts right off on the ramp and runs great as is.

And yes I probably just major jinxed myself

My 98 Pro Gator has a Johnson 50 with VRO oil injection which I've never had a problem with, but after reading this I can't help but wonder if I should delete it or not.....