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nitro5238
11-02-2009, 12:26 AM
I am about to winterize my 1990 PS190. Since the boat is now almost 20 years old I wanted to pull the fuel tank and have a look. I have read on here that crud accumulates in the bottom. My question is after I complete my winterinzing process...you know all the usual stuff...would it be better after I pull the tank ( as I mentioned earlier ) and just leave it completely empty or to go ahead and refill it completely along with fuel stabilizer? The boat will be kept in my attached garage for the winter so cold and condesation should not be any problem. Just curious...what do you guys think?

FrankSchwab
11-02-2009, 12:51 AM
Leave it empty, and fill it with fresh gas in the spring.

/frank

CantRepeat
11-02-2009, 07:27 AM
Fill the tank, add some seafoam and do your winterizing.

An empty fuel tank will have lots of air and can be a great place for condensation to form. Filling the tank with fuel means less air thus less water.

That's just what I've done.

Yellow X9
11-02-2009, 09:21 AM
I run my tank down to less than 1/8 tank, add Stabil to the remaining gas

bigmac
11-02-2009, 09:58 AM
I store mine full to minimize condensation.

trickskier
11-02-2009, 12:37 PM
I store mine full to minimize condensation.

I agree..............I fill-up on the way home after a day at the lake.

Muttley
11-02-2009, 12:39 PM
Another vote for full, with stabilizer.

bigmac
11-02-2009, 12:45 PM
Not sure how much good using a fuel stabililzer actually does, but I use it anyway since I doubt it does any harm. "Can't hurt, might help".

EarlyriserX9
11-02-2009, 01:24 PM
Fill er up

FrankSchwab
11-02-2009, 06:00 PM
He's got NO gas in it right now - it's dry. Do you often have problems with empty buckets filling up by themselves with water where you live?

/frank

CruisinGA
11-02-2009, 07:57 PM
If I had the tank out, open and dry, I would just leave it like that until spring, with fuel lines from the engine capped.

I don't see the rational in buying $70+ in gas to let it age 5-6 months to prevent condensation in a currently dry, open, fuel tank.

mcskier
11-02-2009, 08:09 PM
If I had the tank out and dry, I would just leave it like that until spring.

I don't see the rational in buying $70 in gas to let it age 5-6 months.

...and if you do, it probably ought to be 92 Octane if you are going to store it that long.

Muttley
11-03-2009, 11:17 AM
He's got NO gas in it right now - it's dry. Do you often have problems with empty buckets filling up by themselves with water where you live?

/frank

The "bucket" maybe empty, but they're closed off. Here in the Pacific Northwest, water gets everywhere. If you seal off a bucket, yep, there's gonna be water in it in a few months. Personally I don't want any of that running through my engine.

If he's in a warm, dry climate, he's probably going to be fine. I'd still be running stabilizer through the motor for the stuff in the lines and to prevent the carb from gumming up.

mayo93prostar
11-03-2009, 11:40 AM
leave it empty since you are going to empty it anyways to remove. be sure to grease steering when you are back there.

FrankSchwab
11-03-2009, 02:07 PM
The "bucket" maybe empty, but they're closed off. Here in the Pacific Northwest, water gets everywhere. If you seal off a bucket, yep, there's gonna be water in it in a few months. Personally I don't want any of that running through my engine.

If he's in a warm, dry climate, he's probably going to be fine. I'd still be running stabilizer through the motor for the stuff in the lines and to prevent the carb from gumming up.

I'd be really interested in running that test in the northwest; leave a covered, empty bucket outdoors with a vent that isn't susceptible to rainfall, and see how much water collects over the wintertime.

Unfortunately, it's not a test I can effectively run given my current geographical location.

/frank

TEAL98
11-07-2009, 04:21 PM
FULL :D:cool::D

flipper
11-07-2009, 05:53 PM
I store mine full to minimize condensation.

Same here....and an empty tank is a bomb

Abe
11-08-2009, 09:59 AM
Mine is about half full with fuel additive added, had no probs last year doing it this way. Fuel price over here in The UK again on The rise:mad: should really have filled her up as no doubt it gonna be even more expensive:mad: at the start of next season.

yippikaiyay
11-08-2009, 06:14 PM
Fill it.
One less thing to do in the spring.:D

east tx skier
11-08-2009, 06:26 PM
I used to fill it up, but after talking to my local inboard mechanic, I stabilize whatever is in there before I winterize it. Fresh gas before that first run in the spring is better than old gas. Condensation does not seem to be much of an issue.

bigmac
11-08-2009, 06:39 PM
I used to fill it up, but after talking to my local inboard mechanic, I stabilize whatever is in there before I winterize it. Fresh gas before that first run in the spring is better than old gas. Condensation does not seem to be much of an issue.

I suspect you're correct - full, empty or partially empty (partially full if you're an optimist) probably doesn't make much difference.

TEAL98
11-08-2009, 11:54 PM
I suspect you're correct - full, empty or partially empty (partially full if you're an optimist) probably doesn't make much difference.

Half-Full all the way:D8p

Jerseydave
11-09-2009, 08:52 PM
My buddy has been an inboard dealer (not MC) for 20+ years, and he said these newer plastic fuel tanks don't sweat like the old steel or aluminum ones so condensation is not a big problem anymore. I've been leaving my tank less than 1/2 full with STABIL added, then top it off in the spring with premium to offset any loss in octane.

Just my $.02 :)

get_sum
11-09-2009, 09:44 PM
Full, with stabilizer. I run with breather off, and spray fogging oil (my I/O is carburated) and my wife kills the engine after about 20-30 seconds of fog oil.

babymoore3
11-10-2009, 09:33 PM
Maybe I am off base here, but do plastic / 'glass tanks really condensate much? In a 57 Chevy with thin steel tank I would be concerned...Since the material rapidly gains or loses heat it is more prone to sweating or condensation with temperature swings...

Since heat transfer is based on the conductivity of a material, area, thickness and difference in temperature across the tank wall .... assuming all environmental conditions are the same between the plastic and steel tanks - the conductivity is the only difference.

That of plastic (0.3) is much closer to that of water (0.58) / gasoline (0.15) when compared to steel (46.0) or copper (401)....

To put this in perspective, on a hot summer day - think about touching the wakeboard tower, windshield frame versus the fiberglass on your boat. Yea, both are hot but once we place your hand on fiberglass you can bear touching in the sun. Most times you just torch your hand on the polished metal, right?

Data to back up the discussion....

Temperature ( 77 deg F)
Material/Substance Thermal Conductivity Constant - k - (W/m K)

Air 0.024
Nitrogen 0.024
Fiberglass 0.04
Corkboard 0.043
Fiber insulating board 0.048
Insulation materials 0.09
Plywood 0.13
Gasoline 0.15
Polypropylene 0.18
PVC 0.19
Polyethylene HD 0.47
Water 0.58
Glass 1.05
Steel 46
Copper 401

You can tell it isn't ski season any longer as I have too much time to elaborate on the "boring" details of life!

Jesus_Freak
11-11-2009, 01:45 PM
Maybe I am off base here, but do plastic / 'glass tanks really condensate much? In a 57 Chevy with thin steel tank I would be concerned...Since the material rapidly gains or loses heat it is more prone to sweating or condensation with temperature swings...

Great information.

I am not sure how much fuel tanks, in general, really condense (someone mentioned doing some testing), but I am not sure a metal tank would respond much differently than a plastic tank. The reason I say this is time scale. When you touch various materials on a summer day, the heat transfer time scale is on the order of seconds. Yes, you feel the difference due to conductivities as you pointed out. However, the summer to winter atmospheric changes that are causing condensation (to whatever extent, depending on how low, humidity, etc.) are on the order of days and months. The tank and its contents have plenty to time to thermally equilibrate regardless of the material of construction.