Difference?

[Extemporaneous]

This will be installed for a Westerbeke 46hp.
Is it the right way to go for a diesel filter system?
The 75500MAX is more than 3 times as much money.
Is there something I'm missing?
I see the additional hardware putting the two filters together but is that the sum of the difference?
Can I do some slight plumbing changes and then run them in series (10 or 30 Micron and then 2 Micron) in stead of parallel?
I would also like to replace the T handles for vacuum gauges. I see one on the 75500MAX but it likely measures the overall vacuum. As I right this, unless there is a functional difference, I'm thinking I should just put the two together myself, the way I want it.
Anyway, any help would be appreciated.
Thanks.

Product Specifications
Item Class : Racor Marine Turbine Series
Model Name : 75500MAX
Port Size : 3/4"-16
Maximum Allowable Pressure : 15PSI/103kPa
Bowl Water Cap : 220ml
Overhead Clearance : 4in/102mm
Special Notes
1. See-thru bowls MA/MAX/MAV units are approved for diesel service only. UL Listed USCG Accepted
2. Metal bowl MAM/MAXM units are approved for gasoline and diesel service. UL Listed USCG Accepted

Product Specifications
Item Class : Racor Marine Turbine Series
Model Name : 500MA
Port Size : 3/4"-16
Maximum Allowable Pressure : 15PSI/103kPa
Bowl Water Cap : 110ml
Overhead Clearance : 4in/102mm
Special Notes
1. See-thru bowls MA/MAX/MAV units are approved for diesel service only. UL Listed USCG Accepted
2. Metal bowl MAM/MAXM units are approved for gasoline and diesel service. UL Listed USCG Accepted

[RaptorDance]

You generally want to run one filter or the other. Not both in parallel.

The vacuum gauge basically measures "how clogged" the working filter is. The valve is to switch between filters - handy when underway and your filter clogs. You can also then change the offline filter without stopping the engine.

You can build your own manifold if you want, but the Racor is a very tidy setup.

[Extemporaneous]

I thought......
If I run them in series (not parallel), the first with a 10 or 30 micron and then to the second filter (2 micron), this would give the best filtering without plugging your filters. This way it would allow my secondary filters to go on for ever (maybe not forever).
So the two filters on the 75500MAX are exactly the same?
Perhaps I could set it up where most of the time it ran in series, but with the switch of some valves the fuel could go directly from one or the other of the RACOR filters (leaving the other to be serviced) to the fuel pump and subsequently the secondary filters. That way you could still change filters on the fly. What do you think?
Just trying to get the best filtering I can.

Originally Posted by RaptorDance

You generally want to run one filter or the other. Not both in parallel.

The vacuum gauge basically measures "how clogged" the working filter is. The valve is to switch between filters - handy when underway and your filter clogs. You can also then change the offline filter without stopping the engine.

You can build your own manifold if you want, but the Racor is a very tidy setup.

[RaptorDance]

The Racor housings are the same, it's the filter element that you put in them that have different ratings (30micron , 20 micron, 2 micron, etc.)

If you ran them in series and had a problem, how would you keep the engine running? How would you know which filter you needed to change?

For maximum protection, we always use just the 2 micron elements and keep our second filter off line for changes while running. The 2 micron element is much finer than the secondary filter, which basically we still change, but it's our "element of last resort".

Many folks subscribe to the use a coarser (20 or 30 micron) filter first strategy, but we don't.

[RaptorDance]

Actually, I just looked it up... The filter elements are available only in 30, 10 and 2 micron filtration ratings. Theres a note on the 30 micron size that says that additional filtration is required downstream for this size.

[Extemporaneous]

Filter changes would be initiated via vacuum gauge readings.

Originally Posted by RaptorDance

The Racor housings are the same, it's the filter element that you put in them that have different ratings (30micron , 20 micron, 2 micron, etc.)

If you ran them in series and had a problem, how would you keep the engine running? How would you know which filter you needed to change?

For maximum protection, we always use just the 2 micron elements and keep our second filter off line for changes while running. The 2 micron element is much finer than the secondary filter, which basically we still change, but it's our "element of last resort".

Many folks subscribe to the use a coarser (20 or 30 micron) filter first strategy, but we don't.

[delmarrey]

I'm curious, why would you want to run such a large fuel filter system for your size of boat? Do you have old tanks? The 500FG series should be enough.

I have a 50 hp motor and only use a 10 oz. size canister with a 2 micron filter and I've put up to 200 hours on the filters w/o any problems.

One thing I do, is scrub the fuel at the beginning of each season with a unit below. As well, pull the inspection cover to check for water and sludge.

If your moving from port to port, there are funnels made that can filter out larger particles before it even reaches the tank. And then the 2 micron can do the rest. But it's wise to always carry spare filter elements.

[never monday]

Using a 2 mcn filter for primary filtration can cause a lean conditions and decrease the available power from the engine.
This topic has been debated many time on the forum alone.

[Hud3]

Don't you have a filter mounted on the engine itself?

Most boats have the engine-mounted filter, which becomes the secondary filter when a Racor is added as the primary, giving you two filters in series. You don't need three filters in series, and the Racor 500 MA has more than adequate capacity for your engine.

As Raptor Dance noted, plumbing two Racors in parallel allows you to switch over to the clean one instantly if the one being used clogs. A vacuum pressure gage tells you to switch before the engine lets you know by quitting.

[RaptorDance]

Exactly as HUD3 states. My comment about which filter to change refers to when you have two Racor 500s in series and no backup - with one vacuum gauge between the engine and the 2 filters - when you get excessive pressure - which of the two would you change?

We hadn't discovered this forum when the earlier discussions on using the 2 micron element as a primary filter was discussed. As an engineer, I don't see how that would cause lean conditions unless the element needs changing.

We've used the 2 micron element for years as a primary. No symptoms of lean conditions. Our vacuum gauge reads approx. 0 PSI of vacuum (but it's probably around 1 PSI from the effect of the filter). When we get any noticeable vacuum, we change it.

I'd rather have the safety of a filter that removes the most particulate matter.

Regards,
Bill

[never monday]

Originally Posted by RaptorDance

. As an engineer

A 2mcn filter upstream will 1) clog faster resulting in decreased fuel flow,2) resulting in reduced power and posibly a lean condition.
If you inspect you filters every min of run time you can probably run for years just fine.

Now,
why on earth would you use a filter that has been proven to cause problems and has service bulletins written to not use it.

The engine mounted filter for a mechanical diesel is 5-7mcn. anything smaller will pass thru the pump and injectors and be burnt.


good day.

[delmarrey]

Originally Posted by never monday

The engine mounted filter for a mechanical diesel is 5-7mcn. anything smaller will pass thru the pump and injectors and be burnt.


good day.

The problem is they only come in 30, 10 and 2 micron for the Racor's. I'd run 5 but it's not available. A the smaller the particle the less chance of a injector failure. It's better to be on the safe side.

Even at our fuel sites we run 3 micron screw-on canisters.

[never monday]

Originally Posted by delmarrey

The problem is they only come in 30, 10 and 2 micron for the Racor's. I'd run 5 but it's not available. A the smaller the particle the less chance of a injector failure. It's better to be on the safe side.

Even at our fuel sites we run 3 micron screw-on canisters.

a multi step filter will clean more. A filter is designed to clean 90ish% of the fuel to the advertised level. If you run a 10mcn Racor then a 5-7mcn on the engine. You will clean more fuel to the advertised rate.

AGAIN,
these engines are not sterile spectron microscopes. They can deal with a little (>5mcn) particle and spit it out.

be paranoid or relaxed, it's up to you. I'll just sell more filters to the paranoid.

[David M]

Cummins requires 2 micron filtration on their new B Series diesels. That's what they say so thats what I do if I want to keep my engine warranty...regardless of reality. Therefore I run a 2 micron primary filter with dual Racors.

It does not make any sense to put in 10 micron filters on the primaries and a 2 micron as the secondary on the engine when eventually the 2 micron on the engine is going to clog requiring me to climb down into the engine space and have to change it out?...which is MUCH more of a pain in the rear than changing out the Racors. I have a small engine space but I do have the Racors mounted on the forward engine space bulkhead where they are very easily accessed.

Yes, the secondary filters on the engine should be changed out periodically, but at least you won't be forced to change one out while underway. It can be done at YOUR convenience because it is not getting clogged if the upstream filter is the same "mesh" size or filtration size.

Bottom line, having a smaller filtration size downstream of the dual Racors defeats the purpose of dual Racors.

[RaptorDance]

I've looked at the Westerbeke Service Bulletins and can find no reference to using 2 micron primary Fuel Filtration. see Westerbeke Corporation

I keep an eye on our vacuum gauge and if it reads anything other than zero I switch to the backup filter and change out the clogging one.

We keep our fuel clean, use an additive to keep bacteria down (not excessively), keep out tanks full to minimize condensation and generally keep an eye on things.

In 7 years of cruising with about 2000 engine hours, we've HAD to change our filters only once. We've proactively changed them every few hundred hours (about every other oil change).

So I'm sticking with the 2s.

Regards,
Bill