ISL9 separating fuel filter

[Towboy]

Have a Detroit brand seperator on my freightliner chassis mh. Is there an easier way of changing without getting a bath? I loosened the fuel tank cap to relieve the pressure, parked so nose was lower , drained the bowl completely but the portion of filter that is in the header seems to be trapping about a quart of fuel thus upon removing the the filter fuel gushes out? Should I try draining the bowl with the seperator threaded a little loose to get some air above?

Any ideas?

Thanks John

[wolfe10]

Sure.


Install a diesel-compatible ball valve on the primary fuel filter INLET.


Close it when changing filters or for a great anti-theft device.

[Towboy]

I don't believe a ball valve will make a difference as after the filter was removed no diesel leaked out I had filter off for an hour not a drop I guess cause I had the rear of coach higher than the tank and gravity didn't effect it. Seems there was fuel trapped above the filter in the header.

[wolfe10]

Originally Posted by Towboy

I don't believe a ball valve will make a difference as after the filter was removed no diesel leaked out I had filter off for an hour not a drop I guess cause I had the rear of coach higher than the tank and gravity didn't effect it. Seems there was fuel trapped above the filter in the header.

OK, with no shut-off valve, you have a choice:


If the tank is higher than the filter, fuel will run out-- a lot of fuel.


If lower, fuel will flow/siphon back to the tank making priming a REAL JOB.

[mackwrench]

Originally Posted by Towboy

Have a Detroit brand seperator on my freightliner chassis mh. Is there an easier way of changing without getting a bath? I loosened the fuel tank cap to relieve the pressure, parked so nose was lower , drained the bowl completely but the portion of filter that is in the header seems to be trapping about a quart of fuel thus upon removing the the filter fuel gushes out? Should I try draining the bowl with the seperator threaded a little loose to get some air above?

Any ideas?

Thanks John

Is this a spin on filter with a clear bowl on bottom...or a Davco setup with clear top?

[Towboy]

Detroit clear bowl is on the bottom it seems like fuel is trapped on top of the filter element in the header