Two fuel filters ??

[themannsindorse]

I have a 20' craft with a Vetus 22hp inboard diesel. I changed the Vetus fuel filter yesterday and noticed what looked like another fuel filter on the same line as my Vetus filter hidden away at the back of the engine bay. This filter was twice the size and was before the Vetus lift pump. It was difficult see in the dark but the housing had SOLAR written on it and the words Ram 3522 a written on the cartridge My questions are:
1. Is it normal for any craft let alone mine to have TWO fuel filters and if so WHY?
2. Is it a fuel filter or would it serve some other purpose?

I am tempted just to bypass it but would appreciate opinions first. Thanks. Peter. Wimborne. UK

[DieselTrawlerGuy]

It is very common to have two or more fuel filters. A common practice is to have a courser filter (like a 20 micron - that's the size of particles it will catch) to be first in line coming from the fuel tank and then a 10, 5, 2 or even a 1 micron after that to catch the real small stuff. That would be two fuel filters in series. Then there is the two fuel filters in parallel setup, you are only using one of them at a time and can switch a Y-valve (or more aptly a pair of Y-valves) to go from one to the other. This setup allows you to change one fuel filter while running on the other. It also allows you to change from a clogged filter to a clean filter by simply throwing a couple valves and allows you to change filters later - like in calm seas instead of during rough water.

And if you don't know when that unknown filter was changed then assume it needs changing.

For far more than I can tell you go to the leaders, Racor, at www.parker.com/racor

[noelex 77]

Fuel filtration is important to health of deisel motor. I would be reluctant to remove any filtration.

Most marine engine have a primary and a ( finer) secondary fuel filter.
The secondary fuel filter is normally mounted on the engine, but where access is difficult it may be relocated. This is the most likely explanation for your set up.

It is also possible that there are two primary filters (course and fine).

Often boats are set up with two primary filters so they can swapped over without stopping the engine, but normally they would be identical filters.

[carstenb]

Originally Posted by themannsindorse

I have a 20' craft with a Vetus 22hp inboard diesel. I changed the Vetus fuel filter yesterday and noticed what looked like another fuel filter on the same line as my Vetus filter hidden away at the back of the engine bay. This filter was twice the size and was before the Vetus lift pump. It was difficult see in the dark but the housing had SOLAR written on it and the words Ram 3522 a written on the cartridge My questions are:
1. Is it normal for any craft let alone mine to have TWO fuel filters and if so WHY?
2. Is it a fuel filter or would it serve some other purpose?

I am tempted just to bypass it but would appreciate opinions first. Thanks. Peter. Wimborne. UK

Damn good chance that the filter that is hard to reach is a water separator/coarse filter.

If you can get to it, there will almost certainly be a bolt in the bottom. You put a cup/dish under this, crack it and let it flow. It will be a mix of water and diesel. Let it flow until only diesel comes out (no water). You should empty this on a regular basis (say spring/mid-summer/fall).

Change the filter every couple of years (my yanmar is every 2 years or 500 hours, I believe)

[themannsindorse]

Thanks everyone for your advice. By the time you read this I will be groveling on the cabin floor trying to get at it. Hey ho. all good fun. Post closed