Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 26-12-2012, 01:16   #1
Registered User

Join Date: Dec 2012
Posts: 7
Unleaded Petrol put in Diesel Tank

Finished a cruise and tired crew put unleaded into the diesel tank. Engine was off ...tank has inspection plate ...how do I make sure we get it completely emptied. 31 Moody on a swing mooring with probably 30 litres in the tank - help!
__________________

__________________
Pearcey is offline   Reply With Quote
Old 26-12-2012, 02:26   #2
Registered User
 
xymotic's Avatar

Join Date: Dec 2007
Posts: 1,076
Re: Unleaded Petrol put in Diesel Tank

You don't need to get every last drop, but you just gotta pump it out.
__________________

__________________
xymotic is offline   Reply With Quote
Old 26-12-2012, 03:02   #3
Registered User

Join Date: Dec 2012
Location: Maine
Posts: 1
Re: Unleaded Petrol put in Diesel Tank

Gasoline has a lower specific gravity than diesel fuel, which means that it is lighter, so if you let the mixture sit for a day or so you can siphon the gasoline off from the top since the diesel will settle to the bottom.
__________________
Anthonyd is offline   Reply With Quote
Old 26-12-2012, 04:06   #4
Registered User

Join Date: Apr 2008
Location: Cheyenne, WY
Boat: 1981 Ta Tong Cape Horn Cutter
Posts: 323
Images: 2
Send a message via Skype™ to gts1544
Re: Unleaded Petrol put in Diesel Tank

Pearcey, This might be a great opportunity to "CAREFULLY" clean out your fuel tank! Be sure that any electric pump that you use is "non-sparking" and approved for gasoline! We would hate to lose you! gts1544
__________________
gts1544 is offline   Reply With Quote
Old 26-12-2012, 04:11   #5
mrm
Registered User

Join Date: Feb 2011
Location: Poland, EU
Boat: crew on Bavaria 38 Cruiser
Posts: 651
Re: Unleaded Petrol put in Diesel Tank

Adding gasoline to diesel is a standard operating procedure in very cold climates, especially when one suspects that available diesel was not properly blended for winter. Up to 15% gas to diesel is considered normal then.

In your case, just pump out what you can, fill with diesel and call it done.
__________________
mrm is offline   Reply With Quote
Old 26-12-2012, 05:30   #6
Senior Cruiser
 
Blue Stocking's Avatar

Cruisers Forum Supporter

Join Date: Dec 2008
Location: St. Georges, Bda
Boat: Rhodes Reliant 41ft
Posts: 4,115
Re: Unleaded Petrol put in Diesel Tank

Quote:
Originally Posted by mrm View Post
Adding gasoline to diesel is a standard operating procedure in very cold climates, especially when one suspects that available diesel was not properly blended for winter. Up to 15% gas to diesel is considered normal then.

In your case, just pump out what you can, fill with diesel and call it done.
+1. Did that with 1 of my trucks when new kid put gasoline in the diesel tank. No problem.
__________________
so many projects--so little time !!
Blue Stocking is offline   Reply With Quote
Old 26-12-2012, 07:30   #7
Registered User
 
GrowleyMonster's Avatar

Join Date: Dec 2012
Location: New Orleans
Boat: 1976 Cal 2-27
Posts: 1,298
Re: Unleaded Petrol put in Diesel Tank

A trace left in the tank won't hurt anything. If you are really noid about it, you could try ventilating that tank for a few days. Gasoline evaporates pretty quick. Just beware of where the fumes are going and don't have any spark or flame sources nearby!
__________________
GrowleyMonster is offline   Reply With Quote
Old 26-12-2012, 07:54   #8
Registered User
 
Cotemar's Avatar

Join Date: Dec 2007
Boat: FP, Helia 44 Evo
Posts: 5,717
Re: Unleaded Petrol put in Diesel Tank

Quote:
Originally Posted by mrm View Post
Adding gasoline to diesel is a standard operating procedure in very cold climates, especially when one suspects that available diesel was not properly blended for winter. Up to 15% gas to diesel is considered normal then.

In your case, just pump out what you can, fill with diesel and call it done.
+1, I do this every winter in my VW Jetta Diesel. One gal of gas per 15 gal full tank of diesel
__________________
Cotemar is offline   Reply With Quote
Old 26-12-2012, 09:16   #9
Senior Cruiser
 
Rocketman's Avatar

Cruisers Forum Supporter

Join Date: Apr 2011
Location: Naples, FL
Boat: Beneteau Oceanis 400
Posts: 668
Re: Unleaded Petrol put in Diesel Tank

As noted already, this is not a big problem, but you will need to some how pump the fuel in the tank out and refill it with Diesel. So depending on you tank and where it is located will determine how much trouble it is going to be to pump it out. If your tank is sitting up high, then a siphon tube 10-20 ft long and several 5 gal tanks to hall off the fuel is all that is needed. If your tank is, lets say, to low to allow siphoning, then buy a small electric inlline fuel pump from an auto parts store, then pump it into again 5 gal fuel cans. If you buy the inline pump, you can leave it in the fuel line for future use when you need to prime you fuel lines when you change fuel filters or if your manual fuel pump ever quites you have a spare ready to go.
__________________
Rocketman is offline   Reply With Quote
Old 26-12-2012, 09:20   #10
Moderator Emeritus
 
GordMay's Avatar

Join Date: Mar 2003
Location: Thunder Bay, Ontario - 48-29N x 89-20W
Boat: (Cruiser Living On Dirt)
Posts: 31,583
Images: 240
Re: Unleaded Petrol put in Diesel Tank

Greetings and welcome aboard the CF, Pearcey, and Anthonyd.

I don’t believe that differing specific gravities between two fluids, in a solution, will prevent them from miscibility*.

With two liquids that are completely miscible, such as diesel and gasoline, the overriding factor is misciblity. These liquids will very quickly dissolve into each other, forming a resulting mixture of petroleum hydrocarbons, containing a greater proportion of higher volatile, lower molecular weight, hydrocarbons than regular diesel fuel; but not so radically different from diesel fuel as to warrant pumping out.

* Miscibility is the property of liquids to mix, forming a homogeneous solution.
__________________
Gord May
"If you didn't have the time or money to do it right in the first place, when will you get the time/$ to fix it?"



GordMay is online now   Reply With Quote
Old 26-12-2012, 09:36   #11
Registered User

Join Date: Dec 2012
Posts: 650
Re: Unleaded Petrol put in Diesel Tank

To separate gasoline from diesel, one would need a very tall stack, such as in a refinery. If the 30 litres of gasoline are in a tank of 300 litres or more, just top it off with diesel and you're done. Otherwise, drain most of it and use the mixture as heating oil -- or fuel for a gas turbine.
__________________
mcarling is offline   Reply With Quote
Old 26-12-2012, 09:46   #12
Registered User
 
tommyh's Avatar

Join Date: Nov 2012
Location: SF bay
Boat: Newport 28 II
Posts: 144
Some one did that yo one of our flat beds. The gas distroyed all the seals in the top end and injection system. The truck was never the same again. I would clean it all out.
__________________
tommyh is offline   Reply With Quote
Old 26-12-2012, 10:00   #13
Registered User

Join Date: Jun 2010
Location: Central California
Boat: Samson C Mist 32
Posts: 484
Re: Unleaded Petrol put in Diesel Tank

Growley Monster is right. Be very careful about vapor of petrol
It's heavier than air and explosive. If it contains ethanol I would keep it away from seals as just mentioned.
__________________
Steve Bean is online now   Reply With Quote
Old 26-12-2012, 10:06   #14
Moderator Emeritus
 
David M's Avatar

Cruisers Forum Supporter

Join Date: Sep 2007
Location: San Francisco Bay
Boat: research vessel
Posts: 10,150
Re: Unleaded Petrol put in Diesel Tank

Although gasoline is less dense, it will mix with Diesel. All it takes is a little energy for the mixing to occur, which can come from the boat rocking at the dock. It is not like vinegar and water which will not mix because one is a polar molecule and the other is not.

At the US Naval firefighting school that I went to they used a blend of gasoline and diesel as the fuel source for most of the fires. It does indeed blend quite nicely. The fires by the way had a nice balance between not lighting at all with pure Diesel and incinerating us all or blowing us up using pure gasoline. We were then sent in to dark concrete buildings with a fog nozzle to push back the flames...what fun that was. A petroleum fire can be put out with water if you do it right, but don't try it at home. Use the correct extinguisher for petroleum fires. Sorry, I digressed.

You have to empty the tank but don't worry about what you cant remove because after you fill it up with pure Diesel, the remaining gasoline that you could not remove will be so diluted that it will not matter. Fill it up completely though in order to maximize how much the gasoline is diluted out. Be sure to change your fuel filters and to bleed out any gasoline that might be in your fuel lines.

The biggest problem with gas in a diesel engine is pre-detonation, lack of lubrication and that it can destroy seals.
__________________
David

Life begins where land ends.
David M is offline   Reply With Quote
Old 26-12-2012, 10:08   #15
Senior Cruiser
 
hpeer's Avatar

Cruisers Forum Supporter

Join Date: Dec 2008
Location: Philadelphia
Boat: Murray 33-Chouette & Pape Steelmaid-44-Safara-both steel cutters
Posts: 3,900
Re: Unleaded Petrol put in Diesel Tank

Quote:
Originally Posted by GordMay View Post
Greetings and welcome aboard the CF, Pearcey, and Anthonyd.

I don’t believe that differing specific gravities between two fluids, in a solution, will prevent them from miscibility*.

With two liquids that are completely miscible, such as diesel and gasoline, the overriding factor is misciblity. These liquids will very quickly dissolve into each other, forming a resulting mixture of petroleum hydrocarbons, containing a greater proportion of higher volatile, lower molecular weight, hydrocarbons than regular diesel fuel; but not so radically different from diesel fuel as to warrant pumping out.

* Miscibility is the property of liquids to mix, forming a homogeneous solution.
Yeah, that's what I thought.

I heard two distinct and mutually exclusive ideas roaming about here.

1-That the oil and gas would remain separate and the gas could be pumped out.
2- That the gas and oil would mix and, assuming there was not too much gas, the mixture would be consumable in the engine.

I suspect that if you try to pump it out quickly then you may have some luck. But as the stuff sits and mixes that will become more difficlut.

What I also hears was that a 10% mix of gas into diesel is OK, kinda sorta. But more than that? At what point does it become too much?

So my synthesis of the well meaning advice is:

Pump out the top bit as soon as you can, using a gas rated pump or siphon. Try to get the light gas off the top. Measure it and if you can get a 10% concentration or less you are good. If not, waste the tank of diesel and start over.

Yes?
__________________

__________________
hpeer is offline   Reply With Quote
Reply

Tags
diesel

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off




Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 06:06.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.