Racor fuel filter element replacement

[yelkenli]

I am figuring out my fuel filter system for my new-to-me M18 diesel. I can assume the previous owner had the right parts, but one of the filters has the word gasoline on it. Maybe not relevant. Attached are some pictures of what is installed. It believe the engine mounted filter is correct. I am unsure of the Racor filter. Any information or recommendations are appreciated.

On the engine: 70000-43081
On-engine replacement parts: Fram - P7514, Napa - 3390 - from internet search based on what is on the engine

Installed in engine compartment, fed by electric pump - first filter
Model: 120RMAM; Element: R12S-UL 15GPH/56LPH

I can get the element from Racor and Amazon.

 

[jssailem]

Your twin filter setup is common for boat auxiliary diesel engines.

Racor is a trusted name for diesel engines. It will stop the chunky bits of debris in our fuel systems and prevent water from getting to your engine. There are differing thoughts about the specification of the Racor filter. Should I get a 2 micron or a 30 micron filter? Since 2 microns are smaller particles, that must be better, but not necessarily.

The diesel mechanics I know recommend 30 microns. It is fine enough to block the particulates that can stop your engine, and it will not become clogged so quickly that you need to change the filters every month. Additionally, treat your fuel tank each time you fill with a biocide to keep the fuel clear and your engine running on demand.

Practical Sailor has posted several detailed write-ups about diesel fuel and maintaining a clean tank.

Use the on-engine filter recommended by your engine manufacturer. With the Racor in place, you will not need to change the on-engine fuel filter as often.

Happy Sailing.

 

[Terry Cox]

I am unsure of the Racor filter. Any information or recommendations are appreciated.

Our boat propulsion diesel engine came equipped with a ten micron Racor cartridge primary fuel filter with a ten micron canister engine mounted filter. Our setup seems to work just fine. Our boat Genset came equipped with a ten micron cartridge Racor filter, but a two micron engine mounted cartridge Onan fuel filter. When it came time to change the two micron clogged filter, I changed to a six micron canister filter, which provides ample protection.

 

[WayneH]

On my 1980 W50, I have a 10 micron engine filter and a 2 micron Racor upstream of it. Because every time I had to change the engine filter, I had to bleed the entire fuel system because air would enter the fuel line to the engine pump. Now after a filter change, I turn on the electric lift pump and listen at the fuel tank for the splashing to restart. Did I say it was an old system? LOL

 

[yelkenli]

Thanks for the inputs. I have a better idea of what I am looking at and looking for.

I would expect that the larger micron filter would be upstream (first) and the smaller micron filter would be downstream (second).
Is this correct?

 

[Davidasailor26]

Thanks for the inputs. I have a better idea of what I am looking at and looking for.

I would expect that the larger micron filter would be upstream (first) and the smaller micron filter would be downstream (second).
Is this correct?

Generally, yes. Sounds like that’s backwards for WayneH, but only because it’s easier for him to prime the Racor, so he’s basically using it as the only effective filter.

 

[Clutch Cargo]

Your twin filter setup is common for boat auxiliary diesel engines.

Racor is a trusted name for diesel engines. It will stop the chunky bits of debris in our fuel systems and prevent water from getting to your engine. There are differing thoughts about the specification of the Racor filter. Should I get a 2 micron or a 30 micron filter? Since 2 microns are smaller particles, that must be better, but not necessarily.

The diesel mechanics I know recommend 30 microns. It is fine enough to block the particulates that can stop your engine, and it will not become clogged so quickly that you need to change the filters every month. Additionally, treat your fuel tank each time you fill with a biocide to keep the fuel clear and your engine running on demand.

Practical Sailor has posted several detailed write-ups about diesel fuel and maintaining a clean tank.

Use the on-engine filter recommended by your engine manufacturer. With the Racor in place, you will not need to change the on-engine fuel filter as often.

In many cases, the OEM or one of their major distributors (especially the ones who do re-powers) will recommend the "pre" or primary filter (i.e. the RACOR) micron rating. In the absence of anything else, a mechanical injection engine is typically fine with a 30 µm primary. Some may opt for something finer, but all that means is that it clogs faster and causes performance problems. Electronic injection and especially common rail engines (not typically found on small sailboat auxiliaries) will require a 10 µm primary and the on-engine filter will be 2-5.