How to premix in a built in tank?

[parrisw]

Last year I just used two 6 gallon outboard tanks, and its very easy to pour oil directly into the tank, and easy to see how much oil I need to put in before filling them up so it mixes good. I'm redoing my boat right now, and wanted to put in a bigger built in tank in the bow, now would you fill it up with fuel, and see how much fuel you put in then just add oil? But I'd be worried about it not being mixed, I like putting oil in first then the gas mixes as it goes in, and having a long fill tube for the tank the oil wouldn't go directly in the tank as before??? Maybe I just worry too much.

 

[scooper77515]

Re: How to premix in a built in tank?

The correct way is to premix into external tank(s) and dump in. So take your boat, 5 gallon empty gas can, add premix oil and top off can, shake it, dump in boat, repeat as needed. A hassle, but you KNOW what you have. And it is mixed and not separated in the bottom of your gas tank.

When it comes to pre-mixing for a 2-stroke, you cannot "worry too much".

 

[parrisw]

Re: How to premix in a built in tank?

The correct way is to premix into external tank(s) and dump in. So take your boat, 5 gallon empty gas can, add premix oil and top off can, shake it, dump in boat, repeat as needed. A hassle, but you KNOW what you have. And it is mixed and not separated in the bottom of your gas tank.

When it comes to pre-mixing for a 2-stroke, you cannot "worry too much".

Ok, thanks! That just made too much sense!! LOL. Yes I like to worry. Dam well don't want to blow up my nice motor.

 

[ondarvr]

Re: How to premix in a built in tank?

If you trailer the boat it makes little difference how you do it because about the time you get to the main road it's mixed well. I add the gas and then the correct amount of oil and head to the launch. The only issue you may run into doing it this way is if you don't leave enough room for the oil, but most of the time, even if you over fill it all you need to do is rock the boat and the tank will burp and give you more space.

 

[scooper77515]

Re: How to premix in a built in tank?

I would at least take the oil and mix it with the last gallon or two of fuel, just to thin it out, if you are going to rely on the trailer to mix it. That will greatly improve your chances of having the proper ratio throughout the tank.

Having had a 2-stroke near-miss, and a second one throw a rod, I tend to side with the "overly cautious" side of the argument.

Now I run a 4-stroke, and this is the main reason why.

 

[ondarvr]

Re: How to premix in a built in tank?

Oils are designed to mix easily with even the smallest amount of agitation, so it makes little difference on a trailered boat. If I were at the fuel dock with a low tank I may add some before its full just to make sure.

 

[parrisw]

Re: How to premix in a built in tank?

Thanks guys. I usually error on the side of caution, I usually go to the gas station without my boat anyway, easier that way.

 

[Home Cookin']

Re: How to premix in a built in tank?

add a pint of oil, then 6 gallons of gas. repeat.Or if you think you are near the top, 1/2 pint then 3 gallons. It doesn't ahve to be perfect and by putting the oil in first, you end up with too much not too little.

 

[Frank Acampora]

Re: How to premix in a built in tank?

Now you guys know that the correct way is to add the full amount of gas to the tank, then add the correct amount of oil to the tank, then pick up the back (in your case front) of the boat and shake it a couple of times.

Been drinking and just couldn't resist.

 

[tx1961whaler]

Re: How to premix in a built in tank?

Now you guys know that the correct way is to add the full amount of gas to the tank, then add the correct amount of oil to the tank, then pick up the back (in your case front) of the boat and shake it a couple of times.

Been drinking and just couldn't resist.

To set you mind at ease, take a clear 2 liter Coke bottle, put gas in it (no, it won't dissolve), and carefully and slowly put the oil in it. Do not disturb the bottle. Observe the results for 1 hour.
Then write a paper following the outline given to you in class, and submit it to your 6th grade science teacher, Mr. Smith, no later than Friday. :

 

[ondarvr]

Re: How to premix in a built in tank?

Now you guys know that the correct way is to add the full amount of gas to the tank, then add the correct amount of oil to the tank, then pick up the back (in your case front) of the boat and shake it a couple of times.

Been drinking and just couldn't resist.

If you've been drinking the drive to the launch may shake it up a little more than normal.

 

[Frank Acampora]

Re: How to premix in a built in tank?

Seriously, my fill hose has a low spot in it that will retain about 1/2 pint of oil so I guesstimate how much fuel I will need and put in the correct amount of oil first. After a couple of times, I can now tell by the way the gauge is moving and how far I have cruised, just about how much fuel she will take. If I miss and go a little rich or lean, it will not be so drastic as to harm the engine.

Lots of times I will use 6 gallon tanks in the back of the truckand fill them at a cheap station. Then I mix oil into them and drain into the main tank. Over the course of time, oil ratio stays relatively constant.

 

[metriccrescentwrench]

Re: How to premix in a built in tank?

What, 10 replies to the original post and this hasn't turned into a discussion about ethanol yet!!!!!

I'm with Frank, I can tell pretty close how much fuel I need, and add the appropriate amount of oil first.

 

[parrisw]

Re: How to premix in a built in tank?

What, 10 replies to the original post and this hasn't turned into a discussion about ethanol yet!!!!!

I'm with Frank, I can tell pretty close how much fuel I need, and add the appropriate amount of oil first.

Ya, ethanol sucks!