dumbest fuel filter question EVER.

[charliehows]

and...speaking of primary filters - I discovered my filters cost $5 from a truck parts supplier but $35 from the yanmar parts supplier.

Not complaining and I understand the yanmar guys are trying to survive in a small market, but...caveat emptor.

[olaf hart]

Originally Posted by nuku34

Re Raycor filters: They are generally OK, but the filter elements are absurdly expensive, and the see-through bowls are plastic and prone to cracking.

After various dramas with them, I replaced the whole filter unit with one which is used in the heavy machinery/trucking industry here in New Zealand. Made by Delphi in the UK https://www.delphipartsstore.co.uk/. The filter elements are available in various micron sizes and are about ⅕ the price of a Raycor filter element.

I’m sure there are similar ones made in the USA. As far as I can tell, there is nothing especially “marine” about Raycor.

If you are talking about CAV filters, I suggest you try changing the element in a seaway.
Their other problem is the fuel isn’t passed through the glass base first, it goes through the filter first, so you can’t rely on looking at the condition of fuel in the base, it’s already cleaned and the crud is clogging up above the filter ...
I removed mine and installed dual Racors, it’s the only system to have if you seriously motor offshore.

[Jlp0217]

It is my understanding that the bacteria lives in water at the bottom of the fuel tank, and eats fuel. The black stuff that clogs filters is their excrement. My boat had that problem when I bought it. I replaced the O-ring in the fuel filler and keep it lubricated plus began using biocide. It took about 2 years to quit getting water and black crud in my Racor filter. In 2014, I installed a fuel flow meter, and at the same time added a vacuum guage between the Racor and the lift pump. I haven't changed the filter since, because the vacuum doesn't indicate any clogging issue in the filter. I also never get water in the bowl.

Originally Posted by Chawes

I had lots of trouble with bad fuel. In the heat bacteria grows and when in rough seas it distributes particles from the bottom all over the tank. I use a bioside now.
Also I set up a second Racor with a directional fuel flow valve. If the Racor 10 M clogs I simply switch valve to second fuel filter. I have a 5m on the motor. Yanmar 75 pushing 42 foot sailboat.
So far solution has worked out well.
Cheers

[Sailor_Jeff]

Kurt, very good question. Not dumb at all.

Primary is first filter in line from fuel tank, usually mounted on wall. But you should be asking how to purge the air after the change.

[Tonali99]

Originally Posted by KayZee

The engine is a Yanmar 2gmf. I've mastered oil changes and am moving on to other maintenance and service issues one of these being changing fuel filters.



I'm trying to pre-order parts and discovering the difference between a T and an S filter gave me pause and questions. I'm not on the boat where the manual is and even if I could trace fuel lines from here I don't know if primary means first or most important. I looked at an online shop manual and it didn't give an answer. So without excessive preamble here's the dumb newbie question:


Which is the primary fuel filter? The separator and the bowl or the cartridge in the can with the star shaped screw retainer mounted to the engine itself?


TIA


Kurt

Primary is cartridge, secondary the little can on the engine.

So save yourself an S load of money. Screw the "has to be for the boat" stuff.

Get a fuel filtre bracket and the WIX 33123 heavy duty/offroad equipment filtres.
Much less expensive, has bottom drain to check for possible condensation.
I installed that on my '82 2GM 16 years ago and never had problems.
Replaced it once.

p.s. I also use a squeeze bulb to fill the filtre and prime the engine. But haven't had to unless doing something to the Yannie. Like braided oil/ fuel lines.
Do change the one on the engine.

[Ballsnall]

Primary filter. First in line filtration from the tank, usually includes a water separator. Generally a coarse filter to catch larger particles/bacteria etc.
Secondary filter. Second in line after primary and filters down to OEM spec's. Generally supplied with engine.
Tertiary filter. Optional filtration after secondary and usually same micron rating as secondary. Protects modern engines from contamination introduced during filter changes.

There has been several comments about people only changing their filters after several years. Just note that filters have a shelf life and also a wet life which is typically about 6 months after which the filter my not be providing the protection you expect. Personally, I think one year would not be problematic but a couple of years is probably pushing it especially for cheaper brand names.

[Tillikum]

A manual priming pump is essential IMHO. Best to get a filter housing that incorporates a robust one, and have another larger unit plumbed in. I would not use a squeeze bulb except over a large catchment container as if it cracks the mess and stink below will be a PITA.

[Compass790]

Originally Posted by Ballsnall

Primary filter. First in line filtration from the tank, usually includes a water separator. Generally a coarse filter to catch larger particles/bacteria etc.
Secondary filter. Second in line after primary and filters down to OEM spec's. Generally supplied with engine.
Tertiary filter. Optional filtration after secondary and usually same micron rating as secondary. Protects modern engines from contamination introduced during filter changes.

There has been several comments about people only changing their filters after several years. Just note that filters have a shelf life and also a wet life which is typically about 6 months after which the filter my not be providing the protection you expect. Personally, I think one year would not be problematic but a couple of years is probably pushing it especially for cheaper brand names.

Any evidence for 6 months wet life of filter?
Until I see some evidence I'd call BS on that assertion.
Seen more than a few + 10 year old filters seemingly holding up on little used tractors.

[Marathon1150]

I have previously posted in this thread my preference to use 2 micron filter elements in both the primary and secondary filter units. I have been doing this for more than 15 years on a Perkins 4.108 and it has worked really well. Notably, when I get a clog (see previous post in this thread for some interesting photos), changing the Racor 500 filter is really easy. Changing the secondary filter on a 4.108 usually involves bleeding and until I installed a small electric pump, required turning over the engine most times.

I was recently purchasing filters for a Volvo Penta 2003 which is on our other boat. The Volvo service provider recommended against using 2 + 2 because the fuel pump needs to work harder. At the moment I am declining this advice but I would be interested in hearing opinions from others.

I should note that a PO installed a small electric pump between the primary and secondary filters on the Volvo for reasons not known to me. It makes changing the secondary filter quite easy and it may also be taking a load off the engine-mounted fuel pump. I don't know enough about diesel engines to evaluate this second possibility.

[Davo1404]

Originally Posted by olaf hart

If you are talking about CAV filters, I suggest you try changing the element in a seaway.
Their other problem is the fuel isn’t passed through the glass base first, it goes through the filter first, so you can’t rely on looking at the condition of fuel in the base, it’s already cleaned and the crud is clogging up above the filter ...
I removed mine and installed dual Racors, it’s the only system to have if you seriously motor offshore.

You are dead right about the CAV filters. Archaic design and really hard to change. Bought one of these. A Racor knock off. So much easier to change a filter and no mess.

https://www.scintex.com.au/collectio...nt=37767523779