Diesel Fuel Shower

[Mike and Joanne Stimmler]

This is the second time I've replaced my fuel filters and had no problems the first time but this time after successfully replacing the primary Racor filter bleeding and test running the engine for about 15 minutes, I attempted to replace the secondary spin on filter at the engine and as soon as I started to loosen the filter, the fuel was for some reason under pressure, resulting in the previously mentioned shower. Some condidion must have been different than the first time I changed it out since I surely would have remembered the shower. The tank valve was definitely closed as I think it should be but I'm not sure weather the bleed screw was open or closed, or if that would matter. What did I do wrong? Luckilly I had lots of rags.
Also, Is anyone familiar with the significance of the different colors of diesel fuel? The stuff I put in my boat has a reddish color and some fuel I got a the corner gas station was much More transparent with a greenish color to it. I know that here is a color put in the fuel to show that it has been taxed and possibly the low sulphur and the ultra low sulphur may be colored differently. Can anyone tell me what color goes with what.
I need to be color coordinated for my next shower!!     

[Stu Jackson]

The electric fuel pump creates pressure in the system which stays there. 

You answered your own question; "after successfully replacing the primary Racor filter bleeding and test running the engine for about 15 minutes..."  You built up the pressure by operating the engine.  Just do the Racor filter first to relieve the pressure and don't run the engine and do them both together.  Once you get good at bleeding, you'll realize that if you do them both there's no need to run the engine to check one first.

Color of fuel?  Who cares, buy the least expensive.  From I've read, you're right it's the taxes.

[Rick Johnson]

Winterized diesel fuel is usually green in color. Normal diesel fuel is usually clear or a little amber in color, and non road-taxed diesel (for us boaters and such) is usually dyed red. I've also seen mention of blue for non road-taxed farm equipment.  I think the green and red go good with the season!

[Wayne]

Yes, it is a matter of taxation.
I'm a farmer, and the fuel I buy is exempt from road use tax and is very red in color.  I've never heard of farm fuel dyed blue.  If the revenue folks catch red colored diesel in lets say a pickup truck fuel tank one could be in big trouble.  I'm sure its done lots, though.  We do have to file a use tax exemption certificate with our fuel supplier.

[Ron Hill]

Mike : You're close on the color, but backwards. 
As Wayne said the red diesel does not have the road tax while the straw color is low sulphur and is taxed!!
It's been written up many, many times. That if your Racor is a 2 micron filter size then you only need to change the 10/15 micron spin-on filter every 3-5 years.  A thought 

[Mike and Joanne Stimmler]

Wow! If the diesel fuel we use in our boats is not taxed, then how come it's not cheaper? The price for automotive diesel fuel is about 75 cents per gallon cheaper than the fuel dock, I guess the answer is in the word "BOAT"!

[sail4dale]

WOW ... filter info seems to get more mixed up every time I read these inputs.  The Racor or first filter from the tank should be the courser filter and about 10 -15 microns.  The last filter spin-on on the engine is the finer filter and should be a LESSER  micron rating that the Racor. 
If it is done in reverse, you are essentially negating the use of the spin on and asking for many more Racor filter changes that needed.

I have sold and engineered filtration systems of Parker Hannifin the producer of the Racor brand.

[Ken Juul]

From an engineering standpoint I agree with you.  But because we have so many filters....racor, fuel pump, engine.  The thought behind having a 2 micron racor at the head of the filter line is that of the three it is the easiest to change.  Much harder to change/bleed a clogged engine filter in bouncy seas working around a hot engine.  Then check and clean the fuel pump filter because it is probably fouled also. So much easier to just do the Racor and be back underway.  As for expense, other than the one time I got a load of bad fuel, I change the Racor once a year which I would do no matter which size I used.

[Jeff Kaplan]

i agree with ken about changing the filters once a year. the expence is not great, if you go to other than a boat store,or marina,  and it is cheap insurance. nothing worse than changing filters at sea, fuel spilling and the smell of diesel in a confined area and on ones self is enough to make you sick. go to a place that sells truck parts and order your filters, just bring in the filter #'s for them to cross. baldwin, wix fleetguard, fram  all excellent. racor is racor only...jeff

[Stu Jackson]

Jeff, that's a very good idea.  Reply #7 here: http://c34.org/bbs/index.php?topic=1124.0  gives the nomenclature for the Racor filters.

If you or anyone else has a cross reference guide to the other manufacturer's filters, that'd be great information to post.

[Jeff Kaplan]

i can only speak for the m25, the oil filter is a wix# 51334 and the fuel filter crosses to a fleetguard # ff5226. any truck parts store should be able to cross any #'s except racor, which,btw, can also be bought at a truck parts supplier. you can also get wix filters at napa stores, except will have napa #.  not to get off the topic, but keep these stores in mind for batteries, belts and hoses. i go to marine stores only for what i can't get elsewhere....jeff

[Ron Hill]

Guys : I've written this up at least once before, but it's worth repeating.

I case any of you'all might try to put a course inline filter before the 2 micron Racor, let me give you a few tips - I've "been there done that"!   The reason that I mention inline is that I was unable to find an inexpensive spin on (other than Racor-$$)that could fit under the head sink.
 
You can find all kinds of gasoline inline filters for a 3/8" fuel line.  Pureolator advise not to use a gasoline filter as it wouldn't NOT hold up to diesel!!  That was surprising!! 
I did find a Kohler 3/8" diesel inline filter and tried it.  Worked great, but finally gave it up as it was VERY messy to change (under the head sink as space is limited).
A thought .

[sail4dale]

For a Mk II it does make sense to do it the engineering proper way.  But on the Mk II both filters are accessable ..... the Racor under the aft bunk and the spin on thru the access door stb. side.  This is on the M35 engine.  I've only changed the spin once in 5 years and then just because of the period of time.

On my Cat 30 with the M25 I had the Racor between the tank and the fuel pump and the low micron spin-on at the engine which was readily accessable.  I guess when you can't access one of the filters easily you have to make adjustments.

[Mike and Joanne Stimmler]

My primary fuel filter is the Racor R24S
Secondary at the engine is a Fram P7514

I remember seeing a cross reference list but don't have a copy available.
I thought it came from Ron or Stu

[John Langford]

My MK II takes a R15 filter rather than the much more widely available and slightly cheaper R24. I have to special order them as I have never found them on a chandlery shelf. I wonder if this was only done for a few boats around 1999?