How long is diesel fuel supposed to last in a tank before it causes
problems in injectors? I ran through two full tanks of diesel in 1999
and topped off at the end of the season. But, I then went through a
period where my trips (Hawaii and Alaska) were on other people's boats
and my poor old Catalina mostly sat at the dock. So after four years
of not adding new fuel and the tank drawn down below the 1/4 tank
level, my engine suddenly had trouble starting. The stuff in the fuel
filter didn't smell, look or feel like good diesel so I pulled the
injectors and had them rebuilt, pumped and flushed the tank and whole
fuel system. After adding new fuel it's now running fine again.

My diesel mechanic who rebuilt the injectors says that I might have
gotten gasoline instead of diesel and it would float on top of the
diesel, and until I used down to that level I wouldn't notice any
difference. Is this possible? Could gas have been in there even from
when I bought the boat 8 years ago or during one of my 5 gallon
top-offs? It's a 15 gallon tank and problems arose when I got down to
the last 4 gallons. I had not previously drawn it down below 5
gallons.

Al Gunther - Kingston, WA

You more than likely got water (coeducation) in the tank. To the best of my
knowledge gasolene and diesel will mix. Water and diesel will separate with
the water on the bottom. Also there is an algie of some sort that lives in the
water and eats diesel (or vise versa) and will stop up fuel filters very
quickly.

Look up fuel polishing, a lot of good info there.

I have seen diesel that is 10 + ,years old work fine. It does loose some
potency.

The big problem is keeping it clean.

Mike
***********

How long is diesel fuel supposed to last in a tank before it causes
problems in injectors? I ran through two full tanks of diesel in 1999
and topped off at the end of the season. But, I then went through a
period where my trips (Hawaii and Alaska) were on other people's boats
and my poor old Catalina mostly sat at the dock. So after four years
of not adding new fuel and the tank drawn down below the 1/4 tank
level, my engine suddenly had trouble starting. The stuff in the fuel
filter didn't smell, look or feel like good diesel so I pulled the
injectors and had them rebuilt, pumped and flushed the tank and whole
fuel system. After adding new fuel it's now running fine again.

My diesel mechanic who rebuilt the injectors says that I might have
gotten gasoline instead of diesel and it would float on top of the
diesel, and until I used down to that level I wouldn't notice any
difference. Is this possible? Could gas have been in there even from
when I bought the boat 8 years ago or during one of my 5 gallon
top-offs? It's a 15 gallon tank and problems arose when I got down to
the last 4 gallons. I had not previously drawn it down below 5
gallons.

Al Gunther - Kingston, WA

I would have to concur, condensation forms in part empty tanks, and if you
didn't use the boat much, the water would just collect in the tank and settle
to the bottom! Even just running the engine an hour a week will circulate
enough fuel through a secondary racor filter (assuming you have one, highly
recommended!) to have a polishing effect. Using a biocide such as Biobor TF
will help to keep the bugs undercontrol as well. Just make sure that you
follow the instructions and don't add too much, that causes problems of it's
own!!

You more than likely got water (coeducation) in the tank. To the best of my
knowledge gasolene and diesel will mix. Water and diesel will separate with
the water on the bottom. Also there is an algie of some sort that lives in
the
water and eats diesel (or vise versa) and will stop up fuel filters very
quickly.


Jared Crane