Moving fuel filters

[Krattski]

Hello, I have twin detroit diesel 671ti in my 1984 Ocean 46ss.
I am doing inframes in both engines right now as well as doing some updating, new battery cables, charger, fuel lines, etc.
Servicing my primary fuel filter has always been awkward and messy due to its location. Secondary filter no treat either.
I intend to move them both for both engines to front engine room bulkhead where I have plenty of room and easy access.
New location slightly higher than current and houses slightly longer.
Anyone see any issues with move like this?
Do minor changes in elevation matter?
Thanks

 

[koliver]

Hello, I have twin detroit diesel 671ti in my 1984 Ocean 46ss.
I am doing inframes in both engines right now as well as doing some updating, new battery cables, charger, fuel lines, etc.
Servicing my primary fuel filter has always been awkward and messy due to its location. Secondary filter no treat either.
I intend to move them both for both engines to front engine room bulkhead where I have plenty of room and easy access.
New location slightly higher than current and houses slightly longer.
Anyone see any issues with move like this?
Do minor changes in elevation matter?
Thanks

Some even advocate moving the fuel filters out of the ER, to a place where they can be seen on a frequent and regular basis. Or at least if you use vacuum guages, those can be relocated closer to the helm, for better visibility. As to height relative to the fuel tanks? If they can't be the same height as before the move? No advice here.

 

[rgano]

Minor changes in elevation should prove to be no issue, especially if going downward. If you do not have one already, I would recommend inserting a small electric fuel pump with a valved bypass line into the system upstream of the primary filters. Comes in handy to re-prime filters which might be above current tank levels and to purge air from an injection pump and keep an engine running. My system had the capability to pressurize either engine's primary filter.

 

[Comodave]

Racor makes a priming pump that you install into the filter. I put them in my Racors and it makes priming simple. No additional valves of anything. It does make the Racor 3” taller but it is a very clean installation.

 

[rgano]

Racor makes a priming pump that you install into the filter. I put them in my Racors and it makes priming simple. No additional valves of anything. It does make the Racor 3” taller but it is a very clean installation.

That's a fine thing too, but it doesn't serve as a constant pressure source for an engine faltering with air ingestion problems, an engine you need running right now. The small Facet pump I installed and the valves required to make it happen was probably an afternoon job and saved my bacon.

 

[FF]

To cool the injectors 2 stroke DD usually pump massive fuel thru the engine.

The fuel pump is robust and will hardly notice any difference .

A priming pump at the tank is a help if ever tracking down air leaks.

 

[jgwinks]

The dinner boat I occasionally run has Detroit 8V-71's, from 1964. One time after changing the fuel filters one didn't get seated properly and sucked in enough air to kill the engine. We tried for hours to reprime with no success, and actually had to cancel a cruise. Had to call in a mechanic who set up a portable pump and had the engine running in about 1/2 hour. Sure would have been handy to have electric priming pumps permanently installed upstream of the filters. The leak would have presented itself by leaking fuel out, not sucking air in. And the engine would have kept running. With the stock setup you can't tell until the engine starts running rough, and if you don't catch it quick enough you're screwed.

 

[Lepke]

I have electric fuel pumps between the primaries and secondaries on all my engines. You don't need a bypass line if the electric is rated for a high enough flow. Either the lift pump or electric will draw or push thru the other pump. I use 50 gl/hr rated pumps on the Detroits and 25's on the generators.

 

[rgano]

I have electric fuel pumps between the primaries and secondaries on all my engines. You don't need a bypass line if the electric is rated for a high enough flow. Either the lift pump or electric will draw or push thru the other pump. I use 50 gl/hr rated pumps on the Detroits and 25's on the generators.

But if your intention is to use a relatively small pump to fill those Racors and maybe provide a little pressure for one or two fuel sipping trawler engines, it's better the pumps are positioned before the Racors and have a simple bypass.

 

[FF]

No need for more electric stuff , a large O/B rubber fuel bulb will mount quickly at the tank, and find leaks or push air out quite well.

Might be restrictive for big 50 GPH DD's but worth a try.


KISS!

 

[Unclematt]

I redid my fuel system this year and had a high vacuum problem. Turns out pulling fuel through my in line 125 gph electric pump was the issue. I did a bypass and problem gone. I found this out the long way. I first had 3/8 hose and was told by Racor the run was to long for 3/8 so I installed 1/2 copper through the chase and 1/2 hose connecting it all. I have learned a lot.