time it takes for fuel to carbs & type of Lube

I was thinking of switching to premixing my gas and was wondering if I put stabil and oil in the tank how long will it take to get to all of my carbs(85 140hp v4 rude)? do I need to run engine on lake or will all carbs get mix in it at idle? want to make sure oil/stabil mix is in carbs before winter.

lower unit question is that I have some synthetic pennzoil SAE 75W-90, API GL-5 oil...I am going to replace impeller and housing in the spring should I replace lower unit lube now? is this the right lube? I cracked the drain plug to make sure no water in lower unit and only lube came out.

Re: time it takes for fuel to carbs & type of Lube

I think running your motor for 5 to 6 minutes will be sufficient to get the stabil into your carbs. I would also add some fog to the cylinders after as well. It is best to change the oil every fall, get in the habit of it, to ensure there is no freeze up over the winter months. You dont need to drain the lu oil when you change the impeller, even though the manual will tell you that you do. Good luck.

Re: time it takes for fuel to carbs & type of Lube

If you are using an automotive type of lower unit lub, that's sort of a no-no. Marine lower unit lub is formulated to take a lot higher concentration of water than automotive lub. Lower units are expensive to repair. Use the right stuff.

Re: time it takes for fuel to carbs & type of Lube

At idle the flow rate will be low. It may take a while to get the new fuel into the engine. Also, if you have a large capacity canister-type fuel filter you will have to allow enough time for that fuel to be replaced, too.

What is the total amount of fuel in the fuel system downstream of the tank? Well, it is the fuel in the hoses, the fuel in the filters, and the fuel in the carburetor bowls. That might add up to over 0.25 gallons.

If the flow rate at idle is only 1-gallon-per-hour, then you will have to run the motor for 15 minutes to get enough flow to allow the new fuel to circulate completely into the fuel system. With your V4 engine, it probably has a higher flow rate at idle, but on a modern engine with really low flow rate at idle, it could take a while.