Fuel Filter Question

Excuse my ignorance, but previously on my sailboat I only had one fuel filter to change.....

Currently on our boat, we have a Lehman 120 with three filters leading from the tanks in the following order:

FRAM CCS1136 5 micron (seems to be original)
Racor 500FG with 2 micron (looks to be added at some point)
On Engine Dual CAV @ 10 micron (the stock Lehman filters)

This appears to be what is installed in the boat currently, based on the documentation I have.

I seem to have no choice as to the micron rating for the FRAM or on engine CAV units, but the Racor I can choose 2, 10 or 30. Is the 2 micron what should be installed? If so, does that mean my on engine filters aren't doing a darn thing?

Any advice? Thanks in advance.

Are you certain that they are all on the supply lines? The Fram may be on a return line or on or in conjunction with a fuel flow metering device. I have racors which can, like yours be either 2, 10, or 30 micron prior to the secondary on my Volvo TMD. I typically use the 10 micron on the racors.

hobbystuff said:

Excuse my ignorance, but previously on my sailboat I only had one fuel filter to change.....

Currently on our boat, we have a Lehman 120 with three filters leading from the tanks in the following order:

FRAM CCS1136 5 micron (seems to be original)
Racor 500FG with 2 micron (looks to be added at some point)
On Engine Dual CAV @ 10 micron (the stock Lehman filters)

This appears to be what is installed in the boat currently, based on the documentation I have.

I seem to have no choice as to the micron rating for the FRAM or on engine CAV units, but the Racor I can choose 2, 10 or 30. Is the 2 micron what should be installed? If so, does that mean my on engine filters aren't doing a darn thing?

Any advice? Thanks in advance.

Click to expand...

**** can the Fram unit completely. With having only a 500 Racor I'm use a 10 micron element unless you know you fuel tanks are very clean. If that is the case I'd use the 2 micron element.

A 10 micron after a 5 and 2 makes no sense. The PO of my boat had 2 micron on the main and the 2 at the engine. I blame that for ruining a lift pump. My main filter is 10 then 2 at the engine. By choice I use a 10 micron on the polishing system so, while I change the engine mounted 2 micron on schedule, I rarely change the 10 micron main filter.

Dave

magicbus said:

A 10 micron after a 5 and 2 makes no sense. The PO of my boat had 2 micron on the main and the 2 at the engine. I blame that for ruining a lift pump. My main filter is 10 then 2 at the engine. By choice I use a 10 micron on the polishing system so, while I change the engine mounted 2 micron on schedule, I rarely change the 10 micron main filter.

Dave

Click to expand...

How would a 2 mic filter ruining your lift pump?

hobbystuff said:

Excuse my ignorance, but previously on my sailboat I only had one fuel filter to change.....

Currently on our boat, we have a Lehman 120 with three filters leading from the tanks in the following order:

FRAM CCS1136 5 micron (seems to be original)
Racor 500FG with 2 micron (looks to be added at some point)
On Engine Dual CAV @ 10 micron (the stock Lehman filters)

This appears to be what is installed in the boat currently, based on the documentation I have.

I seem to have no choice as to the micron rating for the FRAM or on engine CAV units, but the Racor I can choose 2, 10 or 30. Is the 2 micron what should be installed? If so, does that mean my on engine filters aren't doing a darn thing?

Any advice? Thanks in advance.

Click to expand...

Where is the genny fed from?

Capt.Bill11 said:

How would a 2 mic filter ruining your lift pump?

Click to expand...

My theory right or wrong was that the lift pump was pulling through too many small filters. But maybe I was jaded by the fine water filter the PO put on the wrong side of the water pump. The PO was a filter maniac... but not in the right places.

Dave

ulysses said:

Are you certain that they are all on the supply lines? The Fram may be on a return line or on or in conjunction with a fuel flow metering device. I have racors which can, like yours be either 2, 10, or 30 micron prior to the secondary on my Volvo TMD. I typically use the 10 micron on the racors.

Click to expand...

I was reasonably sure until you asked - I thought I traced it out as follows - the system feeds from the tanks into the Fram, then it splits at a 'T' one side goes to the generator, the other side goes to the Racor and then from the Racor to the Engine.

But now that you asked me, I'm not sure and have the urge to drive to the boat and find out for sure....

High Wire said:

Where is the genny fed from?

Click to expand...

See my post above on how I think it feeds the genny - but I need to go have a look again.

Ok, so the twin filters that are mounted to the Lehman 120 (see photo) are 10 micron and there are no options otherwise so I am told.

Out of curiosity, if I only had the Racor ahead of the engine mounted filters, what micron filter should I use?

I'm going to pop down to the boat and confirm for myself that I didn't mess up when tracing the lines.

-- Hobbystuff

hobbystuff said:

Ok, so the twin filters that are mounted to the Lehman 120 (see photo) are 10 micron and there are no options otherwise so I am told.

Out of curiosity, if I only had the Racor ahead of the engine mounted filters, what micron filter should I use?

I'm going to pop down to the boat and confirm for myself that I didn't mess up when tracing the lines.

-- Hobbystuff

Click to expand...

My option was to get rid of them and put on a Racor 120 and whatever size filter (2, 10 or 30 I think) that I want on there.....

On 70's and 80's boats the Fram CCS1136 was the water separator and fed the fine mesh filters mounted on the engines. That was pretty much standard setup when purchased new from the dealer. Usually the generator feed was T'd off after the Fram water separator and fed the filters mounted on the generator. Do you have filters on the generator?? If so having both the Fram and the Racor filters in series doesn't make a lot of sense unless they're plumbed in parallel to be backups to each other??

The Racor was most likely added by a previous owners at some point. The order of the filter size doesn't make a lot of sense.

For the older engines, they're both good filters, but it's a bit of overkill. You could re-plumb the Fram as part of a fuel polisher if you wish????

hobbystuff said:

Ok, so the twin filters that are mounted to the Lehman 120 (see photo) are 10 micron and there are no options otherwise so I am told.

Out of curiosity, if I only had the Racor ahead of the engine mounted filters, what micron filter should I use?

I'm going to pop down to the boat and confirm for myself that I didn't mess up when tracing the lines.

-- Hobbystuff

Click to expand...

I have an 1983 Lehman. I have the same set up and use a 2 micron for the Racor (same with PO). I have original steel tanks, so I want everything caught at the Racor. I change the Racor out every 40 hours (2 min-$10). The engine mounted filters were changed out in 2007 and then again in 2013.

magicbus said:

My theory right or wrong was that the lift pump was pulling through too many small filters. But maybe I was jaded by the fine water filter the PO put on the wrong side of the water pump. The PO was a filter maniac... but not in the right places.

Dave

Click to expand...

If that filter was a Racor, The flow rate for their elements is the same whether the element is 2, 10 or 30.

hobbystuff said:

Out of curiosity, if I only had the Racor ahead of the engine mounted filters, what micron filter should I use?
-- Hobbystuff

Click to expand...

With having only a 500 Racor I'd use a 10 micron element unless you know you fuel tanks are very clean. If that is the case I'd use the 2 micron element.

If you move up to a Racor 900, which I suggest you consider, I'd use a 2 micron element.

If it were me, I would Delete the Fram rig. Replace the two CAV cans on the engine with a single spin-on filter adapter kit from any truck supply store or Trans Atlantic Diesel. Then use a proper Baldwin secondary filter. Use one of the two Racors for a fuel water separator at the micron rating SPECIFIED BY THE OWNERS MANUAL (smaller is not always better). Then plumb the other Racor to the genset. You may opt to use both as a 2-stage system, but then you can easily use a spin-on for the genset if you like.

Here are a couple of threads of the fuel upgrade project I undertook:
http://www.trawlerforum.com/forums/s6/fuel-system-upgrade-project-episode-ii-3761.html

http://www.trawlerforum.com/forums/s6/fuel-system-upgrade-project-2798.html (this is the first thread I started about it, but it doesn't end with the project being complete... One of the members gave me a new direction so I started the Episode II thread)

Hope some of this info helps. There are a few threads on the subject. You should have no prob narrowing them down with the search function.

(FYI--- I changed my screen name a couple of years ago from GonzoF1. The quotes in some posts reference that name. Don't want you to be confused.)




Here is a discussion about filter sizes:
http://www.trawlerforum.com/forums/s6/10-micron-enough-4991.html

magicbus said:

A 10 micron after a 5 and 2 makes no sense. The PO of my boat had 2 micron on the main and the 2 at the engine. I blame that for ruining a lift pump. My main filter is 10 then 2 at the engine. By choice I use a 10 micron on the polishing system so, while I change the engine mounted 2 micron on schedule, I rarely change the 10 micron main filter.

Dave

Click to expand...

Why not use a 2 mic filter on the polishing system?

Capt.Bill11 said:

If that filter was a Racor, The flow rate for their elements is the same whether the element is 2, 10 or 30.

Click to expand...

I admit to having not paid a lot of attention to flow rates in physics class, but what I worry about is the "clog" rate. My theory is that a 2 micron will clog much sooner because it is "catching everything" and as it clogs I would assume that the flow rate diminishes.

bligh said:

Why not use a 2 mic filter on the polishing system?

Click to expand...

I thought I had researched this before and the ESI documentation said to use a 10, but on their web site everything is 2. I will have to look into this again.

Dave

There is a lot of good reading material at Baldwin Filters | Home

Back in 2011 (during my fuel project), I had a very good email conversation with an engineer at Baldwin. Here are the bullet points:

One quick question: Why isn't the micron filtration of your filters listed anywhere? Is there something I don't know about filtration that I should know? I have two Racor 500's with a 30m and 10m filter cartridges. I was hoping to have a 2m as the "secondary" CAV filter.

Micron ratings can be fairly complex. It is imperative to know the efficiency (Beta Ratio) associated with the given micron rating. When a company publishes a micron rating without this information, it does not tell the customer how efficient the filter is at the given particle size. For instance, if Company X rates a filter at 15 micron, they may be referencing a nominal micron rating which could mean the filter is anywhere between 50% and 90% efficient at that particle size. Please see the links below for more information about the micron ratings of filters.

http://www.baldwinfilter.com/literature/english/10%20TSB's/89-5R3.pdf
http://www.baldwinfilter.com/literature/english/10%20TSB's/04-2R1.pdf

This series of Racor numbers crosses to our PF598 series. The PF598 is five micron absolute. Therefore, its nominal rating would be at two micron or smaller. If you have further questions, please feel free to contact me.

A good education is to read the fuel filtering articles on boatdiesel. What people do vs what is the text book way is quite different.

But, and a very big one, buy good fuel, keep water from entering your tanks, don't let your tanks get gunked up and use your fuel trumps all on recreational diesel. Judging from all the various responses it seems there are many ways to hook up a filter system that allow us to get by.

The biggest users of hydrocarbon products utilize sequential fuel filtration and or centrifuges. The Parker Hannifin website has a good description of how this works.

BTW, the original poster never cited a problem he is having. It seems his setup is without issue.

Me, 30u on Racor 900 followed by on engine of a reputed 5u. Micron ratings are largely meaningless, it is the beta number that counts. But really, what is your micron size entrapment over time - ever finer as the filter does its job.

Last but not least, a new high pressure diesel is a very different animal. Best to read boatdiesel and sequential 3 stage filtering if you have a newer engine. Works best on older diesels too.

sunchaser said:

A good education is to read the fuel filtering articles on boatdiesel. What people do vs what is the text book way is quite different.

But, and a very big one, buy good fuel, keep water from entering your tanks, don't let your tanks get gunked up and use your fuel trumps all on recreational diesel. Judging from all the various responses it seems there are many ways to hook up a filter system that allow us to get by.

The biggest users of hydrocarbon products utilize sequential fuel filtration and or centrifuges. The Parker Hannifin website has a good description of how this works.

BTW, the original poster never cited a problem he is having. It seems his setup is without issue.

Me, 30u on Racor 900 followed by on engine of a reputed 5u. Micron ratings are largely meaningless, it is the beta number that counts. But really, what is your micron size entrapment over time - ever finer as the filter does its job.

Last but not least, a new high pressure diesel is a very different animal. Best to read boatdiesel and sequential 3 stage filtering if you have a newer engine. Works best on older diesels too.

Click to expand...

Good points.

The real value of forums is to see what others have done and what actually works. The hardest thing is figuring out those that are giving you good info or not...for the most part for simple things like filters...I don't think many just make things up or lie...especially those poster who have met other or are friends of other members who would throw the BS flag if it was too much.


For old iron like the Lehmans...we probably have as many different combinations of storage, use, delivery and filtration of fuel as we have Lehman owners. Many are hoping their Lehman(s) will run forever...other's like me know it just might outlast the boat but may certainly consider a different engine should anything major happen. So using what any other Lehman owner does and works for them and their cruising style and location...well heck it will probably work for you too.

Where I would be text book is if my new boat (even if just new to me) came with a relatively new engine that was expensive and more to the higher performance side of things.

I use 2-micron Racor filters as the primary. When one fails perhaps once a year (can't reach maximum RPM), I switch to the other. They "stand guard" for the filters installed directly on the engine (replaced annually as routine maintenance).



(Life is so much simpler with a single engine. Two propulsion engines and a genset? That's thrice the headaches.)

psneeld said:

...
The real value of forums is to see what others have done and what actually works. The hardest thing is figuring out those that are giving you good info or not. ...

Click to expand...

... especially when they don't/can't provide photographic or other physical evidence.

markpierce said:

... especially when they don't/can't provide photographic or other physical evidence.

Click to expand...

There are certain mechanical, electrical, handyman principles that others with the same skills usually recognize pretty quick. Using those ideas are good if you do enough background checking to ensure safety and longevity of the idea. Actual photographic or other evidence fortunately isn't always needed, but it is comical when there's no response to the challenge...

I know there are many things done on commercial vessels that many here consider blasphemy...I know better because I have seen it in action for years and years under hard use....

So to quickly grasp ideas presented on the forum does take some background in those areas. Those that leave those ideas and projects to yards/other professionals are just another type of boater....no big deal...but when the "leave it to the other guy" types keep blasting that another way ids 'wrong"...my return fire is "how the heck would you know?"

But those types are fortunately few and far between..but I'll bet most know who they are.

psneeld said:

There are certain mechanical, electrical, handyman principles that others with the same skills usually recognize pretty quick. Using those ideas are good if you do enough background checking to ensure safety and longevity of the idea. Actual photographic or other evidence fortunately isn't always needed, but it is comical when there's no response to the challenge... ...

Click to expand...

No doubt.

Ok gents, thanks for all the advice. I was down at the boat tonight and changed all of my filters, just to see what I had going - first time since we bought the boat.

I was wrong about the routing.... from the tanks:

The Racor is first in line, and has a 2 micron filter.
T's off to the generator after the Racor (Genny has its own filter as well).
Then through the FRAM which I am told is 5 microns nominal
Finally to the on engine dual CAV units which are 10 microns

As has been suggested, I think that the FRAM is original, and that the Racor was added when the generator was installed.

Like has been suggested by others here, I think the PO used the 2 micron Racor primary to collect all the junk because it is pretty easy to change and visually verify with the site bowl. Compared to the Racor, the Fram and CAV units on the engine were way more labor intensive to change.

So I grabbed a few spare 2 micron filters for the Racor, and will change them out more frequently than the other two. My visual inspection of the filters and bowls showed most of the crap was in the Racor anyways.

Cheers - Off to Desolation Sound and places North of that for a few weeks.

-- Ryan

the filter on the engine is sized by the engine manufacturer to protect the engine mounted equipment, I would stick with the engine maker's choice.

the filters off the engine are primarily to condition the fuel, the engine filter should ideally never see any contaminants, it is only there "just in case".
personally I dont see anything wrong in having smaller micron ratings off the engine and "in front" of the engine filter particularly with multiple filters in series. if there is only a single filter off the engine using the same micron rating as the engine filter is sensible, typically these are much larger filters

Originally Posted by hobbystuff
Out of curiosity, if I only had the Racor ahead of the engine mounted filters, what micron filter should I use? I would say 10 micron (matching the engine filter)

I had a similar arrangement on my boat. That is, the fuel went from the tank, to a 2 micron Racor 500, through a Fram 5 micron filter than to two secondary filters mounted on the engine.

I changed this to a dual Racor 500 10 micron filter, got rid of the Fram filter and used Delphi HDF296 on my CAV secondary, which are between 5 to 7 microns. If I have problems I can switch to a clean filter with my dual Racor. In the process I went from 13 fuel line connections from the tank to the secondary filters to about 7. The Ford Lehman engine is a tractor engine built to take abuse, 5 micron filters have never given me any trouble.

hobbystuff said:

Ok gents, thanks for all the advice. I was down at the boat tonight and changed all of my filters, just to see what I had going - first time since we bought the boat.

I was wrong about the routing.... from the tanks:

The Racor is first in line, and has a 2 micron filter.
T's off to the generator after the Racor (Genny has its own filter as well).
Then through the FRAM which I am told is 5 microns nominal
Finally to the on engine dual CAV units which are 10 microns


-- Ryan

Click to expand...

Our very similar universal has the identical filter setup, for some reason I don't think the racors were add ons, may be original. The PO never used a filter in the fram unit, the actual filter not the whole unit cost much more than the racors ones.

The Lehman 120 will pass anything below 10 micron. Brian of American Diesel recommends not filtering below 10 micron. In my opinion the filters on the engine are unnecessary with a modern filter like the Racors. The primary should be all that is neccesary. On one of our 120s I have been running it for a year without the engine secondary filters. I run 10 micron all the way so step down filtration was not part of my setup.