Gas Fumes from lazaret fuel tank saturating cabin

[Greg B]

Hello. I have just recently obtained a MacGregor 26s and have done serval modifications.

Now that I have put it in the water the learning has started.
I am having some difficulties eliminating the gas fumes in the lazaret and boat cabin areas. I have tried connecting a breather hose that vents out the transom, but I'm still getting fumes. Even with the fuel tank breather cap closed tightly I am still get gas fumes. This makes everything throughout the whole boat smell like gas . I'm thinking that because it is an older tank potentially fumes are leaking somehow from undetermined places.

I'm thinking I need to redo the whole system, but do not know the best way to go about this. I really want to eliminate all the gas fumes anywhere and everywhere inside the boat. I would assume others have had this problem, and have found a good fix. Does anyone have any good solutions to this problem? Is there a sure fire fix to this problem with having the fuel tank in the lazaret?

Thanks,
Greg

[Be Free]

Greg,
You should not smell gasoline anywhere in the boat. Your tank should not be allowing any fuel or vapor to escape to the atmosphere under normal conditions. You need to find out where the smell is coming from.

I'm sorry, but I can't read the notations on your picture. I'm sure the text would answer my questions if I could read it so please forgive me for asking.

It appears to be an older tank that has been modified with some type of sealant under some of the components and and extra connector fitted in the top. Is/Was the tank leaking fuel? What is the white compound on the top? Is the vertical connector supposed to be a filler, a vent, or perhaps something else?

Bill

[Dougiestyle]

I would get a new tank or find the problem. NO FUMES ALLOWED!!! BOOM BIG BOOM

[NiceAft]

Greg B,

If you were not the person who applied the white sealer, then I would be suspicious of why it was applied. With that sealant now in place, replacing a gasket now may be difficult. I don’t know what that vertical tube is.

Playing around with gasoline and its fumes is not advisable. Purchase a new tank and hoses.

[Tom B]

Get a new tank designed for below deck installation.

[NiceAft]

Get a new tank designed for below deck installation.

Tom B,

If you know of a source, feel free to volunteer it for Greg.

[WinSome]

Hi Greg. Stop using that tank now ! The lazarette is not designed for fuel tank storage as is. Ever. Doesn’t comply with safety rules. A permanent tank can be added by following a few rules and makes for a great to use improvement. Includes air in/out, blower, vent line etc. start with a site search of 26s modifications.Ie : viewtopic.php?p=339703&hilit=Lazarette+ ... nk#p339703
There’s other similar mods on site there. We really liked our modification and cleared out the cockpit. A good winter project.

[NiceAft]

I just finished looking at the 26S manual in our resources section. I didn't see anything about where a fuel tank was supposed to be in a 26S.
In my , the fuel tanks are under the cockpit seats. I believe so on the also. Are these not the correct places
Lazerete has been mentioned often in this thread, so, not being familiar with the , I ask, where exactly did MacGregor intend the fuel tank to be

Is the term Lazerete being used for those areas If so, I don't believe this is correct. To the best of my knowledge, a lazerete is a storage area aft of the cockpit. I'm hoping an S owner will chime in.

[WinSome]

26s intended fuel tank to in the cockpit. I hated it there. A buddy suggested using a wooden cover to make a seat and hide it a bit.
The 26s lazarette is aft storage. But it’s open (not sealed) from the cabin, and unsafe as is, for fuel storage. The upper gaps can be sealed (with foam etc) but they’re also a bilge type bottom drain hole into the lazarette!

[NiceAft]

A photo from any owner would be appreciated. The manual is of no help.

[kmclemore]

One owner's solution:

http://purplesagetradingpost.com/sumner ... de-35.html

http://purplesagetradingpost.com/sumner ... de-36.html

[NiceAft]

I forgot that Sumner had an S.

[OverEasy]

Sniff… sniff…KABLOOIE!

There’s a reason why fuel compartments are either open air or ARE SEPARATE POSITIVELY VENTED COMPARTMENTS,
A fuel tank should NEVER EVER be in a compartment regularly occupied by people.
(REGARDLESS of what others have done or attempted to get away with!)

A fuel tank should never be stored in the lazaret as the lazaret was designed.
It needs to be FULLY SEALED OFF from the full under deck spaces.
The separated fuel compartment of any vessel needs to be fully positively vented.
This means fresh outside air is mechanically forced into the enclosed fuel locker and an unrestricted airflow exit vent is provided.
Last I checked the Proper procedure is to ensure that at least five (or more) full air exchanges have occurred before engine ignition is allowed.

This is a big project for a MacS (or any other Mac for that matter)!

Much better to keep the tank in the open and make a “seat cover board” as mentioned by Winsome.

There are lots of good reputable resources out there starting with the US Coast Guard and Insurance Companies.

Please toss the old tank and get a current compliant tank and keep it in the cockpit (open air) as intended.

Your life and the lives of others are much more importance than a misguided desire for a limited convenience aspect.

Also the use of plumber’s white Teflon tape or compound isn’t appropriate for gasoline.
There are proper appropriate gasoline sealing tapes and compounds available from reputable automotive supply houses.
(Hydrocarbon fuels react differently with white Teflon than water … I believe gasoline grade Compound is Orange and tape is yellow)







Please take the long view and do it right for yourself and others.

Best Regards
Over Easy

[Tom B]

The lazaret can be used for a below deck fuel tank with the addition of Blue Water Yachts passive vent kit. A blower is only required for an engine located in an enclosed compartment. The problem is finding a below deck fuel tank smaller than 12 gallons. Moeller and RDS will make custom aluminum tanks as small as 4 gallons.

[OverEasy]

Once saw a motor sailboat that used two 2 gallon aluminum disposable beer kegs…one on each aft corner… as fuel tanks.
Back in the day it seemed cool…(like I said “back in the day”)…. Wouldn’t recommend that approach nowadays.
Still wouldn’t recommend any interior space fuel tank whatever it might be marketed as.
There is always the potential for any tank to leak or malfunction.

When we modified Over Easy to utilize a pair of new 12 gallon tanks I made sure that all the interface sealant was in seaworthy shape and I modified the fuel cubby drain hole so that there wouldn’t be any possibility of spilled fuel. Now here is where that came into play… The new tanks, when full and heated by the warm weather started to leak from the fuel level sight gage fitting interface.

The current fuel tanks only vent outside air inward to avoid a vacuum, not to vent fuel vapors from the tank!
That was quite an unpleasant surprise.
Fortunately the improved cubby drains worked and the leaked fuel went out of the cubbies into the motor well and then overboard.
Not an ideal situation but better than an open pool of gasoline.

Tanks and fittings can and occasionally do leak.
The last thing I’d want is a fuel leak in the cabin space.
I’d still suggest keeping the fuel tank out of the cabin space environment.

Best Regards
Over Easy