ANDAIR fuel filter question

[simatos]

I am servicing my Andair fuel filter which unscrews exposing the filter element.
The unit has an "O" ring to seal once reassembled. Im wondering if it would be necessary to use grease or some other material on the "O" ring to ensure the seal or should it work dry?? Look forward to any comments from anyone who has been down this road, Cheers Gary

[Bevan]

I always apply a tiny amount of Fuel Lube to the o-ring and massage it around. I think it makes it easier to the bowl get on/off and may protect the o-ring from the gasoline as well as making a better seal. I have one andair gascolator in each wing root where there?s not a lot of room to get a grip.

Bevan

[APenner]

After my last annual, this o-ring ended up broken and a fuel leak resulted. It had been lubricated with fuel-lube. Fuel-lube is very thick and that may have caused the o-ring not to seat properly. My AME recommended using ordinary engine oil.

[agent4573]

The lube doesn't help the sealing directly, it's just there to make sure things slide back into place correctly. A drop of engine oil is always my go to for o rings.

[JTJones]

This is from Andair:

Undo the safety wire, unscrew the fitting then unscrew the safety wire end from the filter case. Blow the exposed filter out on an airline and swill it in clean fuel to remove any contaminants on the outside. Do not allow debris to get on the inside of the filter. Reassemble using grease or petroleum jelly. Safety wire as it was.

[rvbuilder2002]

Originally Posted by APenner

After my last annual, this o-ring ended up broken and a fuel leak resulted. It had been lubricated with fuel-lube. Fuel-lube is very thick and that may have caused the o-ring not to seat properly. My AME recommended using ordinary engine oil.

Originally Posted by agent4573

The lube doesn't help the sealing directly, it's just there to make sure things slide back into place correctly. A drop of engine oil is always my go to for o rings.

Oil works but a better choice is Dow Corning #4 (commonly refered to as DC4)
It is a silicone grease.
Any silicone grease intended for o-ring seals would be a good choice.

[flyinga]

"Undo the safety wire, unscrew the fitting then unscrew the safety wire end from the filter case. Blow the exposed filter out on an airline and swill it in clean fuel to remove any contaminants on the outside. Do not allow debris to get on the inside of the filter. Reassemble using grease or petroleum jelly. Safety wire as it was."

It's amazing what you can learn from reading the available product technical data.

[swisseagle]

The O-Ring sometimes swell a tiny bit, so after you took it of (for greasing it), you will have a hard time to put it back. The chance of cutting the O-Ring during the re-assembly, is high. Had is once, since then, I spend the money and replace the O-Ring, if I open the filter.

[simatos]

thanks Gentlemen, oiled reassembled and no leaks
Cheers Gary