RV-12 Fuel pump fitting installation

I started installing the fuel system yesterday. Instruction requires installing AN816-6-2D fittings into the ES 40105 Fuel Pump. It seemed to require a significant amount of force to install the fittings. I'm a little concerned- is that normal?

I used Boelube to trial fit those fittings, turning with wrench until relatively tight (what ever that is) then unscrewed them, cleaned and applied thread sealant and reinstalled. Using this procedure I was able to tell how many turns to expect until tight - especially important on angled fittings that have to end up in a specific orientation. When all lines were complete I pressure tested and did not observe any leaks. Hope this helps.

I understand your reasoning for the Boelube Jerry, but this is not something I would recommend.
Boelube is a wax based lubricant. Getting all traces of it off the threads (particularly the female half of the joint) could be difficult. Any left behind could result in a leak.

I had used Fuellube during initial install because I thought it was the way to go (it is also advertised as a thread sealant). After some hours I had a small leak near the red cube and now with my 100hr inspection I discovered a small leak at the fuel valve. Redid all the fittings with Loctite 567.

The fittings at the pump will not go in all the way. From what I remember I had to use a wrench also for the initial turns. As soon as the force builds up I fastened it one more "flat". You will end up with two/three threads showing.
The fittings at the fuel valve are a different story because you have to align them. It also can take considerable force to turn them the last 1/2 turn.

Thanks for the input- I appreciate the information. I guess may primary concern is the force required to seat the fitting. Once about 50% of the threads were engaged I needed a box wrench with the fuel pump in a vice to complete the remaining 50%. It was a dry installation with a little Loctite.....so much force that upstream, female side of the pump started to move.

I used thread sealer from Auto Zone. Three years and no leaks.

Jim Gries said:

Thanks for the input- I appreciate the information. I guess may primary concern is the force required to seat the fitting. Once about 50% of the threads were engaged I needed a box wrench with the fuel pump in a vice to complete the remaining 50%. It was a dry installation with a little Loctite.....so much force that upstream, female side of the pump started to move.

Click to expand...

A much better practice anytime you see a hex. shape that you are threading a fittinng into, is to double wrench while tightening (I.E. put a wrench on the hex portion and on the fitting).

Clamping something like a fuel pump in a vice and allowing all of teh tightenng torque of the fitting to be directed into the pump can result in damage.

rvbuilder2002 said:

I understand your reasoning for the Boelube Jerry, but this is not something I would recommend.
Boelube is a wax based lubricant. Getting all traces of it off the threads (particularly the female half of the joint) could be difficult. Any left behind could result in a leak.

Click to expand...

Scott, I use the liquid boelube and accoring to their website "Boelube does not contain Silicone, Sulfur, Halogens (such as Chlorine), Phosphorus, Paraffin Wax, Petroleum or Heavy Metals." Of course it is a proprietary formulation so they don't tell you what it does contain. I guess time will tell.

JerryH said:

Scott, I use the liquid boelube and accoring to their website "Boelube does not contain Silicone, Sulfur, Halogens (such as Chlorine), Phosphorus, Paraffin Wax, Petroleum or Heavy Metals." Of course it is a proprietary formulation so they don't tell you what it does contain. I guess time will tell.

Click to expand...

I stand corrected.
I guess I should have said a wax like lubricant. All I know is the only solvent I have found that works seems to remove it is wax and grease remover.