WELCOME TO RIVER DAVES PLACE

Old gas

colenighthawk

Well-Known Member
Joined
Jan 22, 2013
Messages
316
Reaction score
234
My boat has been sitting since November last year, prior to storage I've added stabil 360 to each gas tank , I have a 625 Ilmore and it take 91. With work and busy life, I didn't have time to get on the water. I'm planning on getting it on the water next week, should I run it, add octane buster or drain the gas tank and put fresh gas. The tanks are 90% full of gas. What would you do?
 

Ultra...Good

Well-Known Member
Joined
Jul 10, 2021
Messages
53
Reaction score
110
Run it, gently. I run whatever I have left from previous year, gently, and I do not use Stabil. What will you do with gas if you did drain tanks?
 

colenighthawk

Well-Known Member
Joined
Jan 22, 2013
Messages
316
Reaction score
234
It's been sitting in my warehouse in Anaheim, but I boat in Havasu.
 
Last edited:

ham&cheese

Member
Joined
Feb 3, 2016
Messages
268
Reaction score
434
My boat has been sitting since November last year, prior to storage I've added stabil 360 to each gas tank , I have a 625 Ilmore and it take 91. With work and busy life, I didn't have time to get on the water. I'm planning on getting it on the water next week, should I run it, add octane buster or drain the gas tank and put fresh gas. The tanks are 90% full of gas. What would you do?

Pay someone to siphon out the old gas for you.. Way less money then what a motor will cost if you hurt it. Especially with having a Ilmore 625
 

lbhsbz

Well-Known Member
Joined
Jan 11, 2010
Messages
8,267
Reaction score
16,722
How many gallons is 90% full?
 

LargeOrangeFont

Moderation Enthusiast
Staff member
Joined
Sep 4, 2015
Messages
32,108
Reaction score
45,727
If you put stabil in it and it mixed and ran through the fuel system, run it gently.
 

Mikes56

Well-Known Member
Joined
May 11, 2019
Messages
591
Reaction score
954
I have a Mercury 525 in my Conquest. Each year for the past 7 years of ownership, I add double the recommended amount of Stabil in the gas tanks and run the boat for the last outing, usually in late September. The next year in May or June I run the boat in my driveway on the garden hose to make sure it will start, so I don’t have a problem at the lake for my first launch of the season. It’s always started first time, runs great and has never given me a problem. My boat sits outside, covered, with a silver tarp over the cover.

Im sure you will be fine to just run it. If it makes you feel better to go easy on it, just do that. The new motors have so many sensors on them that I don’t think it will let it hurt itself.
 

ChrisV

Well-Known Member
Joined
Nov 30, 2020
Messages
245
Reaction score
529
Dump the gas and put new gas if you wanna rip on it. If not, run the old gas.
 

Mandelon

Coffee makes me poop.
Joined
Sep 24, 2007
Messages
11,689
Reaction score
12,161
Does Gas Go Bad?
In short: Yes! We explain why and tell you what you can do about it

AUTOBLOG STAFF
Last Updated: Thu, 26 Mar 2020 12:40:00 EDT

Does gas really go 'bad' if left unused for a period of time? Some people are convinced this is just another urban legend, and that people who worry about 'old gas' and spend money on fuel stabilizer are wasting personal effort as well as cash. But gasoline can in fact degrade over time, which leads to a number of problems, ranging from hard starting to rough running to no starting at all. So, does gas go bad? Yes it can.

Here's Why Gas Goes Bad
Unlike crude oil, gasoline is a highly refined product brewed to a certain chemical composition with very specific characteristics. One characteristic of gas is volatility, a term used to describe how easily and under what conditions the gas vaporizes so it can be efficiently burned in your car's engine.

The most highly volatile components in gasoline also tend to evaporate over time. As they do, the remaining fuel's volatility and ability to combust properly will degrade. The less volatile the fuel, the less effectively it burns in your engine. The result is diminished engine performance. Your engine may still start and run, but it probably won't run as well.

The good news: Once the old gas has been consumed and the tank is topped off with fresh fuel, the problem should cure itself. Evaporation of volatile compounds can be limited by making sure the gas cap is secured tightly. For the same reason, be sure all portable gas containers are sealed tightly as well.

A More Serious Problem: Oxidation
Hydrocarbons in the gas react with oxygen to produce new compounds that eventually change the chemical composition of the fuel. This leads to gum and varnish deposits in the fuel system. These deposits and impurities can clog up gas lines and filters, as well as the small orifices in a carburetor and the even smaller orifices in a fuel injector. Removing these deposits can be expensive and your vehicle may not run at all or run very poorly until they are removed.

Water Contamination
Condensation can form inside your gas tank and lines from heat cycling. Fuels such as E85, which have a high concentration of ethanol alcohol, may be even more susceptible to water contamination, as ethanol likes to draw moisture out of the surrounding air. Water contamination can be a problem at gas stations with light traffic due to a slightly different kind of heat cycling. The underground storage tanks experience increases and decreases in temperature. This can cause moisture to form and contaminate the fuel. When you fill up at such a station you're pumping in the water along with the gas. Such low-traffic stations may also have other contaminants in their underground storage tanks, such as rust. They are best avoided whenever possible.

Water, of course, does not work too well as a fuel in an internal combustion engine. It will cause hard starting and rough running until it's purged from the system. It can also contribute to internal rusting of the gas lines and tank. The resultant scale and small particles can create a true nightmare, sometimes requiring the replacement of the gas lines and tank at considerable expense. You can reduce the chances of water contamination by keeping your car's gas tank as close to full as possible, especially if the vehicle is going to be left idle for an extended period.

How Do You Identify Bad Gas?
One way is to eyeball it. Oxidized fuel often turns darker over time and may even smell sour. You can check stored gasoline by pouring some into a clear glass container and comparing it side-by-side with known fresh gasoline. If your old sample looks noticeably darker than the fresh gas, you have strong evidence the gas has gone bad.

How Long Does it Take for Gas to Go Bad?
That depends on a number of factors. For one, it's hard to know how old the gas you just bought actually is. It may be fresh from the refinery, or it may be a month old already by the time you top off your tank. Some gasoline is mixed with better (or more) oxidation inhibitors than others.

It's a good rule of thumb to avoid leaving gas in your tank or a storage container for more than a couple of months. That's if – of course – you can avoid it.

And if You Can't?
If you know gas will sit in your tank or a storage container for a couple months, then it's a wise move to buy some fuel system stabilizer and mix it in with the gasoline. Do it before you put the vehicle into long-term storage or before leaving your lawn equipment fuel containers sitting for the winter. The stabilizer helps prevent oxidation, the biggie that can turn gas into garbage that gunks up your system and leads to expensive repair work.

Using fuel system stabilizer for extended storage is preferable to draining the tank and leaving the system dry. This can cause rubber hoses, gaskets and seals to dry-rot and crack, possibly leading to leaks and even a fire. In addition, a dry system can expose the insides of metal fuel lines and your gas tank to air and moisture, which can lead to or accelerate the formation of rust.

Fuel system stabilizer is not a cure-all and it doesn't last forever. It must be mixed with fresh gas before the vehicle is stored, not added to already old gas. It can slow down the oxidation process and keep gas fresh for as long as 12 to 15 months. If you're going to leave the vehicle parked for longer than that you may want to drain the tank and refill with fresh fuel before returning the vehicle to service.
 

Mandelon

Coffee makes me poop.
Joined
Sep 24, 2007
Messages
11,689
Reaction score
12,161
I always just topped off my tank with fresh gas and ran it like usual. Never had any issues. I did start every few weeks on the trailer during the off season.
 

colenighthawk

Well-Known Member
Joined
Jan 22, 2013
Messages
316
Reaction score
234
Drop it in at the marina, idle it all the way to the channel, pull up and idle it all day there while you play horribly offensive hip hop until the gas is all gone.


That sounds like a good idea, but how did you know that I play horrible offensive gangster shit music?
Am I allowed to idle in the channel all day?
 

Sharp Shooter

The "anti-yuppie"
Joined
Oct 4, 2007
Messages
5,523
Reaction score
7,351
Even though I've gotten away with running some nasty rotten gas before in carbureted engines I would siphon it out. Siphoning is easy so why not?
 

CJ_Donahue

Well-Known Member
Joined
May 24, 2018
Messages
1,085
Reaction score
2,462
I have always filled up just before launching. I do it so when I tow home it is lighter and so I am able to do at least a 50% fresh on the first trip every season. 90% full would be my only concern.

You said Anaheim right. I bet alot of us are local and at $4 a gallon I would bet a few of us would happily stop by and take a truck full each.
 

Jay Dub

Well-Known Member
Joined
Jun 11, 2020
Messages
422
Reaction score
474
My boat has been sitting since November last year, prior to storage I've added stabil 360 to each gas tank , I have a 625 Ilmore and it take 91. With work and busy life, I didn't have time to get on the water. I'm planning on getting it on the water next week, should I run it, add octane buster or drain the gas tank and put fresh gas. The tanks are 90% full of gas. What would you do?
when you filled your boat last season did you fill with "standard" E10 pump fuel or ethanol-free? If ethanol-free, you are good. If E10, (although stabilized) I would drain as much as you could. I would run the old fuel in my cars/trucks.
 

Riverryder

Well-Known Member
Joined
Aug 15, 2019
Messages
1,340
Reaction score
1,167
I would drain it don’t risk it. I did it last year and yet I can’t blame it all on the gas but I think it help the motor along with it grenading itself.
Like these guys have said also I always fill the boat before launching but I also run my boat a lot. I can’t sit at a beach or the channel all day.
 

COCA COLA COWBOY

Well-Known Member
Joined
Aug 19, 2011
Messages
3,643
Reaction score
2,748
Drain the tanks!!!! Put the gas in your daily driver. Never run old gas no matter what. You can buy a siphon on ebay with a little ball that makes it easy or if your a baller buy an electric fuel pump and drain them. I used to pull a hose after the pump and thread on another hose to get it to the fuel jugs and turn the key. It would take about 30 seconds per gallon.
 

GETBOATS

Well-Known Member
Joined
Apr 29, 2013
Messages
343
Reaction score
458
I've heard it put like this, putting new fuel on top of old hoping somehow the new will make the old new again is like.............realizing the gallon of milk half gone in the frig that expired 3 weeks ago will be all good by adding new milk. Dump it! and start over. :rolleyes:
 

Riverryder

Well-Known Member
Joined
Aug 15, 2019
Messages
1,340
Reaction score
1,167
@Hallett Dave thanks. I have some of that. But after all the research I did. It’s snake oil. The amount you would need to bring octane up even 1 would cost double of just gettin 100. I throw 100
In my boat every once in a while.
 
Top