On Mar 28, 3:39 pm, Wayne.B wrote:
On Wed, 28 Mar 2007 14:50:08 -0500, Don W

wrote:
I'd like to hear more about your fuel system
setup. It sounds interesting.

It's very straight forward.

I have no day tank.

Each engine has the usual engine mounted filters.

Ahead of each engine is an array of 2 Racors (total of 4), each with a
ball valve on the intake and outlet. This allows either filter to be
selected or isolated, or both filters could be in paralell.

The output side of the Racors has a vacuum guage to monitor the
condition of the filter. In the event of a higher than normal vacuum
reading I open the valves for the backup filter, and close off the
valves for the old filter. The old filter is now isolated and can be
changed on the fly.

In between the Racor's and the engine mounted filter is an electric
fuel pump which is normally valved off and unpowered. If I need to
prime the engine mounted filters, the electric pump is valved in and
turned on. This forces fuel into the engine filters and though the
injection loop to the fuel return. This could theoretically be used
for polishing but I don't because I have a separate polishing loop
with its own pump that just draws fuel through the Racors and sends it
back to the tank.

So... you just bleed the air off at the filter housing as you "prime
it"?

Joe

On 28 Mar 2007 20:14:27 -0700, wrote:

So... you just bleed the air off at the filter housing as you "prime
it"?

The DD injection system is self bleeding as long as it's receiving
pressurized fuel. Usually a minute or so with the priming pump is all
that's necessary.

On Mar 29, 5:42 am, Wayne.B wrote:
On 28 Mar 2007 20:14:27 -0700, wrote:

So... you just bleed the air off at the filter housing as you "prime
it"?

The DD injection system is self bleeding as long as it's receiving
pressurized fuel. Usually a minute or so with the priming pump is all
that's necessary.

Thats OK as long as your engine is not to hot, and it does not take
to long to get all the air thru the system. DD injectors use fuel flow
to keep them cool.

Joe

On 29 Mar 2007 06:35:08 -0700, wrote:

The DD injection system is self bleeding as long as it's receiving
pressurized fuel. Usually a minute or so with the priming pump is all
that's necessary.

Thats OK as long as your engine is not to hot, and it does not take
to long to get all the air thru the system. DD injectors use fuel flow
to keep them cool.

You don't run the engine when priming so heat is not an issue. Most
times if I'm using the priming pump it's because I changed one of the
engine mounted filters which I always do cold anyway.

On Mar 29, 9:47 am, Wayne.B wrote:
On 29 Mar 2007 06:35:08 -0700, wrote:

The DD injection system is self bleeding as long as it's receiving
pressurized fuel. Usually a minute or so with the priming pump is all
that's necessary.

Thats OK as long as your engine is not to hot, and it does not take
to long to get all the air thru the system. DD injectors use fuel flow
to keep them cool.

You don't run the engine when priming so heat is not an issue. Most
times if I'm using the priming pump it's because I changed one of the
engine mounted filters which I always do cold anyway.

What if both filters clog offshore?
You going dead in the water in a storm while swapping filters?

I thought that was the purpose of having two filter housing and piping
them to shift from housing to housing.

Joe

On 29 Mar 2007 08:30:02 -0700, wrote:

What if both filters clog offshore?
You going dead in the water in a storm while swapping filters?

I thought that was the purpose of having two filter housing and piping
them to shift from housing to housing.

You must be misunderstanding something. Because of the dual
switchable Racors in front of the engine it is very unlikely that
either of the engine mounted filters will ever clog. I replace them
periodically as routine maintenance only.

The Racors require no priming.

Since I have twin engines fed by separate tanks and filters the
probability of ever going dead in the water is very slim.

On Mar 29, 1:52 pm, Wayne.B wrote:
On 29 Mar 2007 08:30:02 -0700, wrote:

What if both filters clog offshore?
You going dead in the water in a storm while swapping filters?

I thought that was the purpose of having two filter housing and piping
them to shift from housing to housing.

You must be misunderstanding something. Because of the dual
switchable Racors in front of the engine it is very unlikely that
either of the engine mounted filters will ever clog. I replace them
periodically as routine maintenance only.

Same here, I have baldwin secondarys engine mounted.

Here's the problem I've seen a hundred times. You are offshore your
tanks are being sloshed hard, so every thing is floating and knocked
loose, the first PRIMARY clogs, you switch to your second Primary and
it clogs. So you have to change one primary to get going. In doing so,
in a storm, you are not going to be able to get all the air out of the
Racor canister.

Then if you try to push air through the engine you are asking for
problems. Lots of cranking ect and if your electric fuel pump fails
you could become airbound. Nothing like getting airbound in a storm
with a loaded boat.

I like the sound of everthing you are doing except pushing air
through the fuel system.

PS: I have over 400K miles under my belt on boats that had a min of
3.. 12-71 TI's and as many as 5, with 2, 4-71 natural gen sets. Dealt
with many 16-149 TI ****balls as well.

Joe






The Racors require no priming.

Since I have twin engines fed by separate tanks and filters the
probability of ever going dead in the water is very slim.

"Wayne.B" wrote

Since I have twin engines fed by separate tanks and
filters the
probability of ever going dead in the water is very slim.

Famous last words?

They said the Titanic was unsinkable, too.