Racor 500 series fuel filter and fuel level therein

[hamburking]

Originally Posted by svthreecheers

I believe the 200 is a spin on cartridge

No cartridge/spin on, full to the top (see picture).

[Capt Doug]

I have the Racor 500, had problem with fuel level etc. I moved to a dock for the summer, Dog wants air conditioning, had not started engine in about four months. After messing with hose, clamps, etc.. I decided to take the racor completely apart. There is a marble sized ball acting as a check valve. The black sluge was thick enough to stop a heart or fuel flow. cleaned it completely and have had no problems since.

[antoha]

part of the logic (as to why before the pump rather than after) is that if pump sucks from the racor and you have bad clamping or some such, you at worst will suck air and starve the engine; if it's after - you could expel fuel out of the system, which is much worse.

there are probably many other reasons, but racor explicitly wants you to put all their fuel/water filter/separators on the suction side of the pump.

[captain mitch]

The racor should ALWAYS be full - or at least full way above the plastic housing!
Any less and you will pull air into the engine -- they do not run well on air.
Look carefully at the top edge of the plastic bowl where it meets the metal housing. It is possible that while you had the system apart, the plastic bowl got cracked near the collar (I have seen that many times).
Anyway, look UP stream from the Racor, that is the most likely area, if the racor is not the source of the air.

[Cheechako]

Originally Posted by hamburking

No cartridge/spin on, full to the top (see picture).

Just a FYI: Cant tell how full from your pic. "Full to the top" means you have to remove the clamp and top and look inside the metal housing...

[Shenandoah]

"The Racor filters 5oo/900/1000 series are never all the way full when the engine
is running."

Sorry, Siggi - disagree.

The filter housing should stay full. If there is air at the top of the 500/900/1000 filter housing, then there is an air leak in the system. Ideally, there should be no air from the fuel pickup in the tank to the nozzle of the injector. The height of the filter housing allows the air to collect there rather than go into the output lines.

[Laser fun]

Thanks for all the input. To clarify, clear bowl of Racor is full and the fuel level does remain above the inlet and outlet ports. The fuel level just remains about 2-4 oz short of filling the housing to the removable lid. Thanks all.

[jongleur]

Originally Posted by antoha

part of the logic (as to why before the pump rather than after) is that if pump sucks from the racor and you have bad clamping or some such, you at worst will suck air and starve the engine; if it's after - you could expel fuel out of the system, which is much worse.

Why would "expel fuel out of the
system" be any different of a problem
than "expelling" fuel out of any fitting
anywhere in the line? Why would there
be more or less chance of this with the
fuel filter before or after the pump?
There should simply be no leaks anywhere
in the system.

It helps to protect the pump that way.

What difference to the pump is there before
or after the filter? ...and the pump only costs
about 60 bucks. I carry a spare.

[antoha]

Leaking fuel anywhere in the delivery system is clearly no good, I agree. My lift pump though is mounted on the engine, and the fittings are robust (properly sealing with rubber o-rings and what not). Installed by a professional I trust, etc etc (all arguable points, but assume for the moment). In any case, there's just one point in the fuel delivery system after the lift pump which may get touched (when say changing the lift pump, which btw costs around $300 from the westerbeke dealer - again, getting around paying full price would be a separate thread).

There are many more connections in the fuel system before the lift pump (installed/maintained by me, and potentially touched more frequently): to the vacuum gauge between the Racor and the lift pump, then between the vacuum gauge and the Racor, between the Racor and the valve, then between the valve and the tank. If you have more then one tank it's even more complicated. Most connections are those silly tapered threads and not the straight threads with an o-ring (those are only on the Racor itself, but my hoses are not like that). I don't have a way of pressure testing all those field serviceable connections.

So having more asymptomatic potential failure points (well, it's leaking, but engine is running just fine and a bit of fuel in the bilge may have come from a sloppy element change) is worse than being able to detect that smth is wrong right away.

And since I mentioned a vacuum gauge: monitoring it tells you if the filter element needs changing (hard to suck results in more vacuum, which is what the gauge measures). Wouldn't be the case if the Racor were after the pump.

When everything works fine nothing really matters, but sooner or later everything fails. In my book, asymptomatic development of potentially catastrophic failure is worse than showing symptoms early.

[Rustic Charm]

Originally Posted by jongleur

It helps to protect the pump that way.

What difference to the pump is there before
or after the filter? ...and the pump only costs
about 60 bucks. I carry a spare.

The filter 'filters' dirt and grime. That's its purpose. To 'filter'.

If you use cheap pumps, that's fine. If you don't mind replacing them that's fine. Your boat, you do whatever you like with your boat.

[svHyLyte]

Originally Posted by Cheechako

With the screw out you have no vacuum to draw fuel into the filter......right? To fill it up you would need a pump prior to the Fuel filter. Most are installed before the lift pump that I have seen.
...

On our yacht, as on our previous yacht; and, as on most of the yachts I have been acquainted with, the lift pump was before the fuel filter(s). Further, on our yacht, as on our previous yacht, the top of the fuel tank is well above the top of the fuel filter in which case, with adequate fuel in the tank, one doesn't need the lift pump at all to fill the fuel filter canister, which fills via gravity once the locking screw is released slightly. This arrangement, coupled with the check-valve in the FG500, prevents one getting air in one's fuel feed line and, consequently, needing to "bleed" ones engine, something I have not had to do for upwards of 10 years.

FWIW...

[Terra Nova]

The Racor belongs on the suction side of the pump.

[Laser fun]

Just completed another 30 minute engine run. With the filter element removed before and after the difference in fuel levels in the Racore filter was two and 6 ounces. It's still above the inlet and outlet port level, but below the top of the Racor. Prior to the engine run all the clamps were checked for tightness and no diesel is leaking into any recesses on the boat. When sumping the Racore filter housing the flow was very weak. It has been 10 days since we replaced the element due to water contamination. Time for a new element?

[hamburking]

Originally Posted by jongleur

What difference to the pump is there before
or after the filter? ...and the pump only costs
about 60 bucks. I carry a spare.

I would consider a diesel "fountain" spraying my engine room with the contents of my fuel tank a big problem. Pump after primary filter makes sense to me.

[Snore]

Originally Posted by Laser fun

Just completed another 30 minute engine run. With the filter element removed before and after the difference in fuel levels in the Racore filter was two and 6 ounces. It's still above the inlet and outlet port level, but below the top of the Racor. Prior to the engine run all the clamps were checked for tightness and no diesel is leaking into any recesses on the boat. When sumping the Racore filter housing the flow was very weak. It has been 10 days since we replaced the element due to water contamination. Time for a new element?

Did I put paper under the fuel line and pumps? From experience it is very hard to see small drips.


Sent from my iPhone- please forgive autocorrect errors.