Non Ethanol Gas (Boat)

[skeeter2010]

I have been tasked with getting a relatives boat running which has been sitting for about 4-5 years. It had/has high octane (93) non ethanol gas in it. It is a large boat with twin 502's and large fuel tanks the boat may have close to 100 gallons in it currently and I believe it holds close to 200 gallons. It is currently on the water on a lift and would be difficult to pump it and carry it out. Any thoughts on trying to run it on the current gas? it does have water filters for the fuel. I know we need to have the carbs checked/cleaned and fluids changed. Do you think the gas will still have enough octane in it to run the engines? I don't think it will hurt to try it since the fuel is filtered.

 

[slimcake]

I wouldn't chance it. If it was fuel injected maybe. Can you pull a sample and see what it looks/smells like? If those 502's have high compression shes gonna sing nasty tune on 5 year old gas....

 

[Skylar]

I wouldn't chance it either. Pump it all out.

 

[old abe]

Bad deal!!! No good gas!!! Get rid of it all.

 

[G]

It is maybe supposed to have 93 in it but you really have no idea who filled it and with what. Major pain to get it out but if I were you I would get rid of it all. The shelf life on that gas no matter what it was expired a long time ago.

 

[snoluver1]

Personally, I wouldn't be so quick to just say dump 100 gallons of gas without doing a little investigative work first. If it truly is 93 non eth, and it was bought at a marina, it is a much higher quality gasoline than the ethanol crap we buy at the standard pump. It should have a much longer shelf life. Granted, it has surely broken down some, and the octane has probably dropped off, but that could be fixed with the simple addition of fresh gas. I would pull a sample, from the bottom of the tank. See what it looks like and check for water. If it has turned an orange color or smells like varnish, its too far gone. If it is still clear and smells ok, it might be salvageable. Top it off with fresh to get the octane back up and run her.

 

[slimcake]

Top it off and then have 200 gallons to get rid of? Seriously. If you have $$ to run a boat with 2-502 inch motors this should be a no brainer. Dump the gas and start over. Post something at the highschool about free gas at the marina and get kids to carry it five gallons at a time.

 

[snoluver1]

You have a good point slim, i guess i wouldn't know what it's like to just toss $400 worth of gas, without a second thought. Regardless, it wouldn't really be hurting anything to see if the fuel still lights. One of 3 things will happen: 1) it won't run = dump the fuel, 2) it will run like crap and ping like crazy = dump the fuel, 3) it will run ok = top off with fresh and throttle down. Any way you look at, your not going to damage a four stroke carburated engine by trying to run it on bad gas for a couple minutes.

 

[ac600sp]

I'd pump it out and get some fresh fuel. Mix a few gallons of the old fuel with a full tank in a vehicle, only if the gas doesn't have water or tons of varnish in the fuel. 502 engine need a good octane fuel to run proper, it's a very expensive engine to risk damage just to save some cash on not getting fresh gas.

 

[srt20]

The boat is at least 4-5 years old.
The guy had enough money to buy a boat with two 502 engines.

Easiest way to fix this issue is to trade it in on a new 150K boat....

 

[snoluver1]

Just out of curiosity, what exactly is it that you guy's are thinking will be damaged by running old fuel? If the gas is bad (low octane) the only consequence i can think of is detonation. You can clearly hear this as a "ping" or knocking noise, especially under load. Detonation will not damage a four stroke motor instantaneously like a 2 stroke. If you ran it a long time under heavy loads, or down a drag strip, yes it could be very bad. However, it's not nearly as critical as in a 2 stroke engine. If you inspect the fuel first, change the filters and check for water, then fire it up. If it pings, shut it down and drain the gas. If it doesn't, run it. What else could possibly happen?

 

[favoritos]

Just out of curiosity, what exactly is it that you guy's are thinking will be damaged by running old fuel? If the gas is bad (low octane) the only consequence i can think of is detonation. You can clearly hear this as a "ping" or knocking noise, especially under load. Detonation will not damage a four stroke motor instantaneously like a 2 stroke. If you ran it a long time under heavy loads, or down a drag strip, yes it could be very bad. However, it's not nearly as critical as in a 2 stroke engine. If you inspect the fuel first, change the filters and check for water, then fire it up. If it pings, shut it down and drain the gas. If it doesn't, run it. What else could possibly happen?

No kidding. Top off the tanks. Those motors will burn through that in no time.
I would be more concerned about the oil in those big block motors after they sat that much time.
Bad thing is that you have a big boat to get back in to shore if something fails. Run it, but have a friend with another boat for a tow. Swimming a boat to shore is not fun. That boat is too big for that option.

 

[ac600sp]

If the boat has been sitting for several years, the carburetors will need to be cleaned and all the fuel filters. Why would anyone run old gas through a fuel system that has just been taken apart and cleaned. Just my thoughts

 

[snoluver1]

The carbs may or may not need to be cleaned. If it started out with high quality non eth gas, you may not need to touch them. Otherwise, you have a tiny amount of gas sitting in a fuel bowl that may have evaporated off and left behind varnish deposits, in which case you would need to clean them. Still doesn't mean the 100 gallons in the tank is necessarily bad. I think too many here have snowmobile engines/fuel systems on the brain. Totally different scenario. I agree it might be a long shot, but worth a try before condemning 100 gallons of fuel. Your not gonna kill a four stroke engine by giving it a shot. Gasoline is refined from all kinds of different base stock. High quality fuels refined from straight crude oil can last many many years.(AV gas for example) Corn gas is junk after a couple months.

 

[ezra]

screw all that dumping fuel. I have a big tank in my boat last yr I never even toped it off cuz t still had over 80gal of 2yr old gas in it . ran it I do have efi but no diff if u just clean the carb before running . I would fire it up and burn some of it off at 1/2 ish throttle . u should have no prob smelling if the fuel is bad . man what a huge pita to try to pump out a a big boat I would need at least 15/20 feet of hose just to reach the tank .
the other thing it was prob stored with startron .

 

[eao]

What you going to do with the gas that is pumped out? How much will that cost and who will do that. My friend had to pay a lot of money to get rid of the fuel oil (and tank) that was in the house he purchased about 5 yrs ago so I can imagine it will cost a lot of money to dispose of 100 gallons of gasoline. PS - The house was converted to gas long ago but they never removed the fuel oil tank.

 

[Tracker]

I have been tasked with getting a relatives boat running which has been sitting for about 4-5 years. It had/has high octane (93) non ethanol gas in it. It is a large boat with twin 502's and large fuel tanks the boat may have close to 100 gallons in it currently and I believe it holds close to 200 gallons. It is currently on the water on a lift and would be difficult to pump it and carry it out. Any thoughts on trying to run it on the current gas? it does have water filters for the fuel. I know we need to have the carbs checked/cleaned and fluids changed. Do you think the gas will still have enough octane in it to run the engines? I don't think it will hurt to try it since the fuel is filtered.

this is an....ALCOA.....YOU MAKE THE CALL....lets go over it eh skeet.....20 dolla electric pump....check....5 gallon empty gas can...check.....using (maybe) at farm/mower/slash fire starter all year long 100 gallons wasted = 400 bucks....check.....total bill.....500 bucks maybe......rebuilding 2 502 EFIs.....15,000+ each....check.....500 dolla wasted VS 30,000+ wasted.....sitting for 5 years......??????.....you gotta fever?....epilepsy?.....steven hawking twitch?......one eye sealed shut?.....sloped forehead?.....what is it man?....that makes you not think clearly.....LOL....if your OK using that gas to power your vehicle with your family in it to cuba and back with no radio...then yes...go for it....i'll look for ya on the evenin news there...LMAO

 

[whitedust]

What you going to do with the gas that is pumped out? How much will that cost and who will do that. My friend had to pay a lot of money to get rid of the fuel oil (and tank) that was in the house he purchased about 5 yrs ago so I can imagine it will cost a lot of money to dispose of 100 gallons of gasoline. PS - The house was converted to gas long ago but they never removed the fuel oil tank.

X2 no idea who will pump it out and what to do with that much gas? Check into legal disposal first.

 

[snoluver1]

Like talking to the wall around here. I guess common sence, logic and science have no skin in the game? Please explain to me how trying to start a 4 stroke v8 on some possibly stale fuel, is going to result in catastrophic engine failure.....awe nevermind, I'll just go back to my corner now.

 

[slimcake]

Like talking to the wall around here. I guess common sence, logic and science have no skin in the game? Please explain to me how trying to start a 4 stroke v8 on some possibly stale fuel, is going to result in catastrophic engine failure.....awe nevermind, I'll just go back to my corner now.

If ya don't mind cleaning carbs twice than by all means have at it. That is a for sure. Not in my engines. nope.