View Full Version : Foiling fuel thieves.

04-10-2001, 02:40 PM
I usually leave the gas tank on my Chris Craft full in order to reduce condensation. But one day last season when I checked the fuel level before launching, the tank was only about one-third full. Hummm...I refilled the tank, messed around on the lake, and after docking, topped off the fuel. Several days later the tank was two-thirds empty again...

...Sure are a lot of goons on jet-skis out on the water, burning up a lot of gas...

The dock is in an isolated location, and I can't be there all the time to keep an eye on the boat. Although homicide is not considered a VERY serious offence in our state, I hate to waste the bullet. Anybody got any good ideas?

04-10-2001, 02:46 PM
Disconnect the deck hose where it goes into the tank, install a smaller tank below decks with at least 15 gallons or so, but large enough to make it worthwhile. Fill this tank with a combination of gasoline, sugar and very fine valve grinding compound......should show results on a two stroke in short order............

04-10-2001, 08:33 PM
well you could try and sind a screen to put inline so the hose wouldn't get through to the tank. or even put a bad bend in it so their hose wouldn't make the turns required to get to the gas ???

Dale Harvey
04-10-2001, 08:36 PM
Drill a 1/8 or smaller hole in the bottom skirt of the cap and slightly into the threads of the fill neck. Thread hole for a tiny stainless allen screw. Add a small allen wrench to your keychain.

Rob H
04-10-2001, 09:25 PM
Realistically, now, your best bet is to leave the gas tank nearly empty. If you try getting clever with jerks like that you're just challenging them to get more "creative" with your lovely Chris-Craft.

I mean, if I were some punk kid on a jet-skeet, and some absentee boatowner tricked me into sugaring my own engine with his gas, I'd burn his boat to the waterline, right?

I love indulging fantasy as much as the next guy, but I assume you're looking for a workable solution.

04-10-2001, 09:38 PM
Darn....you guys are just no fun!!!!!

John B
04-10-2001, 10:41 PM
And then carry a bottle of meths for the condensation.

04-11-2001, 12:14 AM
T fitting in fill line that leads to empty (small) tank. Close valve between small tank and T to fill large tank, siphoners find valve open, suck drips out of small tank.

Or some such; you have to be sneaky these days, lest they get angry.

Grandfather's farm fuel tanks were mislabeled; every couple of years a thief would fill his car with diesel.

ken mcclure
04-11-2001, 07:46 AM
Shang - ah - (ahem) - ummm - you DID take a sniff of the bilges, didn't you?

04-11-2001, 08:24 AM
Yeah, the first time it happened I almost tore the hatchcover off, fearing that thirty gallons of gas might be sloshing around in the cellar...

It's fun to fantasize, but realistically I like the T-connection leading to a near-empty tank idea. Locking the gas cap would also be simple, but might tempt some goon to use a pipe wrench, and Mitch LaPointe gets $125 for CC gas caps.

My solution last season was to reverse the boat in the slip, clear the field of view from shore, and install proximity-activated spot lights which turn on day or night if someone comes onto the dock.

04-11-2001, 09:55 AM
well, lessee.....a little nitromethane mixed with the gas............

jack grebe
04-11-2001, 10:35 AM
ummmmmmmm i wonder what a lit cig. and bout 3 gal. of that liquid oxygen would do ummmmmmm could find out in bout 3 sec.

04-11-2001, 11:38 AM
As much as I like the trick & decoy method http://media5.hypernet.com/~dick/ubb/biggrin.gif

How bout a locking gas cap?

Either that or a ball valve down the filler tube. Once they figure out they can't get to the fuel...

I'm also a fan of the video camera
Once you have a few shots of them in action ...

04-11-2001, 12:04 PM
for just $4500 asummer I'll go there and stand guard over youer boat...yep that's right 24 hr watches. yeah Iknow it's a cheap price, but we can do it because of low over head.
how far is the local bar from youer boat?
how fast is youer boat?
any ladies nearby who would like a boat ride on youer boat?

04-11-2001, 01:45 PM
If you really want to get nast.....and not very expensive....a small video camera that is sensitive to Infrared light, with several I.R. diodes turned on. Camera less than 1 x 1 inch and same for invisible lights hooked to video recorder with a switch that activate when someone steps on the boat and runs for 3 minutes at a time or when gas cap is removed. For a hundred bucks or so you can post the thieves picture all over the marina.

04-11-2001, 03:24 PM
In the interest of creative brainstorming, there is another avenue we haven't explored:

My neighbor's dock is a couple of hundred yards upstream, and he's had fuel pilfered too. Maybe we could collect money for a legal defense fund, and talk HIM into sitting up all night on shore and shooting this clown. ...You know, just wing the guy a little...

04-11-2001, 03:31 PM
...For a picture of the boat in question, go to:

...Appreciate your offer, B Leggett, but as you can see, there's not a bar in sight, and all of the pretty ladies are hiding behind the trees on shore.

Alan D. Hyde
04-11-2001, 03:32 PM
But what if he misses, and hits the boat???

ken mcclure
04-11-2001, 03:54 PM
Undoubtedly, the answer is to get yourself a BFD.

In layman's terms, a big dog.

Feed him sparingly.

04-11-2001, 05:25 PM
Well now...I got this ole yeller dawg that I done brung up from Florida. Ugly critter he is, real short legs and long snout, great teeth. We chopped off his long tail and couldn't stand the silly green color so we painted him yeller........wanna borrow my pooch "Ally" for a while.......

Mike Vogdes
04-12-2001, 08:00 AM
Hey Shang,

All you would have to do is to swap your gas hose with your holding tank hose, put the holding tank line to the gas deck fitting..

I could just picture some jet skier along side your boat with a syphon hose in his mouth, boostin a little gas (poop) from your boat.

Would also make a great submission to "Funniest Home Videos"...

04-12-2001, 11:04 AM
You're an evil man, Mike... I like your plan...

Rob H
04-12-2001, 08:36 PM
Just don't flush your cigar butts down the loo!

Ed Harrow
04-18-2001, 11:56 AM
Hey, I got an idea; I think it would work, and they'd be hard pressed to trace it to you. Get yourself some Poison Ivy (once leafed out) and rub it thoroughly all over the gas cap. (Just don't you forget!) By the time things start to itch, I'll bet they will be doing a LOT of itching in a LOT of places.

04-18-2001, 12:41 PM
Temporarily hook your fill line up to a tank full of diesel.

If they smell it, they'll assume you switched engines.

If they're stupid enough to use it, it's put a rod through their engine!

04-19-2001, 09:07 AM
The only fuel-additive I can think of which would preclude retribution would be some formula which would explode and totally vaporize the fuel-snitcher about 200 yards down the lake, but then the wreckage might pose a hazard to navigation.

Here's a question: Responding to the fuel-theft problem, my mechanic suggested putting moth balls in the gas tank; but when I asked him what that would do he just chuckled evily. Was this a put-on? What would be the effect of moth balls in the fuel? ...Other than keeping moths out of the gas?

04-19-2001, 11:42 AM
Don't mothball have something like naptha in them?

Ed Harrow
04-19-2001, 11:50 AM
Mothballs. I remember reading something about mothballs and gas a loonnngggg time ago. What's in mothballs, chemist. Nitro, LOL?

I do remember the article stating the the odor of mothballs drifted across the environment after the vehicle passed by.

Also, my daughter is trying to find a good home for a 130 pound junkyard dog at the humane society. He's a really great dog, and NOBODY would want to get close enough to find out. He kind of reminds me of Beau, our prior dog. Beau was bigger, tho maybe not heavier, same junkyard/brindle coat, and petrified of lound noises. A ballon was just about all that was needed to get him to run for the nearest corner, or behind the hutch (But that's another story).

Mike DeHart
04-19-2001, 12:34 PM
An old hot rodder told me he used to mix moth crystals (paradichlorobenzene) with his gas, but he specifically said "not moth balls." He says it made his car run faster. I don't know if it boosted the octane or if it added volatility to the fuel or if it served as an oxidizer. I never tried it. If only there was something to keep the iron moths away from the fenders of my old truck...

Scott Rosen
04-19-2001, 04:08 PM
As tempting as it would be, I don't think you should make any alterations to your fuel lines. Every valve is a potential leakage point, and it wouldn't take much of a breach in your fill line to cause some major problems with gas vapor in your bilge. In fact, I would bet that the Coast Guard regs don't permit a shutoff valve or a Y-valve in the fill line for just that reason.

If I were you, I'd try not to leave the tank full. You can fill up at the beginning of your next day on the water. If condensation really is a problem, you could install a high quality fuel filter that has a water basin to catch the condensation before it gets to the engine. Or you could add a pint of dry gas (methanol) to the fuel at each fill-up to "dissolve" the water.

I think a locking gas cap would look out of place on your boat, and would just encourage the thieves to be more brazen.

Nasty problem. Good luck.

04-20-2001, 07:39 AM
Yeah, Scott, you are right. As much fun as it is to fantasize about surrounding the dock with floating mines, and creatures which could chew a thief's leg off; the truth is that the most conservative cure is the most practical.
I've cleared the field of view from shore, installed proximity floodlights on the dock, relocated the boat in the slip, and put house and yard lights on timers to give the impression that someone is watching day and night. We'll see what happens in the coming season.

Art Read
04-20-2001, 11:02 AM
.... and perhaps a little note informing the culprit(s) that you HAVE noticed and will henseforth be watching would give pause... Chances are they assume you've never missed it not realising how carefully you've kept her topped off...

ken mcclure
04-20-2001, 11:18 AM
Well, how about a less physically threatening approach. As Brian suggested, set up a video camera and equip it with nightvision. Catch them on tape. Turn them in to the police and file criminal charges.

[This message has been edited by kwmcclure (edited 04-20-2001).]

04-20-2001, 02:14 PM
Digital cameras are Infrared Sensitive. Hang out some infrared lamps in the area and aim the digital camer appropriately and put the remote camera activator on one of thos auto "jiggle" switches to take a series of picutres when activated...........I still think nitromethane is the answer........

04-20-2001, 05:49 PM
The problem with this is that you have to worry about the goblins stealing the cameras. Lost a good Nikon and Sun strobe I had set up in the woods to take photos of deer long ago; I refuse to believe that they took it. They would have taken the tripod as well.

05-23-2003, 07:55 PM
How 'bout a quiet camp out aboard, when you think thievery most likely. A twelve gauge citizen's arrest. Have your cell phone handy to call the local constabulary.

'Course, they'll get off with a slap on the wrist, but word might spread about that twelve gauge on a dark night. Never know when Bruce might be lurking.

05-23-2003, 08:35 PM

I must've lived a charmed life; I've never been ripped. Traveled far and wide, often leaving things unlocked. Where I live now I don't lock my door. 'Course the only thing worth stealing might be this computer.

The good Lord looks out for fools and drunks. smile.gif

05-23-2003, 11:08 PM
"...Shang, did you lose any more fuel? ..." --Ironmuel

Gee, a Blast from the Past...
...Naugh, the floating mines worked pretty well, and the torpedos from the Q-boats finished those ratzbastrards off.

Ken Hutchins
05-24-2003, 09:03 AM
What you need is a north country burglar alarm. Ya a big bear leg hold trap, :D set it right next to the boat, they have a chain for attaching to a fixed object so he can't run away. :D Perhaps attach it to a large chunk of concrete for transfering to some deep water after the alarm is tripped. :D