douglassmt

douglassmt

Well Known Member
OK, I've looked through the posts and can't find this anywhere. So help.

I'm installing fuel and oil lines FWF and need to know what torques to use. I have the table for aluminum fittings from Van's FAQ page, but don't know if those apply for fuel and oil lines. I could use the "flats" method, but thought I'd check for numbers first. How do I figure out what size (-6, -8, etc) the lines are?

Second, what does one use for lube on the fuel and oil fittings, if anything? Tite seal, fuel lube, thread lock or nothing? Probably just on threads, not sealing surfaces?

Help would be appreciated. As usual, several qualified responses are expected :)
 
B-nut and Pipe thread torque

From our manual:


INSTALLATION OF PIPE THREAD AND O-RING FITTINGS


The torque values listed are recommended values, these DO NOT supersede any published airframe/engine manufacture publication.

PIPE THREAD FITTINGS

? DO NOT under any circumstance use Teflon tape.

?Approved sealants are Permatex Thread Sealant #14 or Loctite 565 PST.

Recommended Pipe Thread Torque Values

? Torque 1/8? NPT fittings to 45 ? 65 inch pounds.
? Torque 1/4? NPT fittings to 70 ? 110 inch pounds.
? Torque 3/8? NPT fittings to 95 ? 135 inch pounds.
? Torque 1/2? NPT fittings to 110 ? 140 inch pounds.


O-RING FITTINGS and AN FITTINGS

?DO NOT under any circumstance use pipe thread sealant, ?Gas Tite? or Teflon tape on O-ring fittings. No sealant of any kind is required on flared fittings or B-Nuts.

? Apply a film of motor oil to the O-ring before installing the fitting.

Recommended O-Ring and Flared Fitting Torque Values

?#4 Plugs 20?25 in-lbs., #4 Hose B-Nut 25-35 in-lbs., #4 Bulkhead Nut 45-50 in-lbs.

?#6 Plugs 30?35 in-lbs., #6 Hose B-Nut 30-40 in-lbs., #6 Bulkhead Nut 90-100 in-lbs.

?#8 Plugs 45?50 in-lbs., #8 Hose B-Nut 60-80 in-lbs., #8 Bulkhead Nut 150-250 in-lbs.

?#10 Plugs 60?65 in-lbs., #10 Hose B-Nut 100-150 in-lbs., #10 Bulkhead Nut 200-350 in-lbs

? If the fitting leaks around the O-ring seat, replace the O-ring, inspect the O-ring port for scratches or nicks.

? If fitting leaks around flare fittings inspect the flare for scratches, or improper flare. Inspect the AN fitting for nicks or dents on the taper of the fitting where the flare seats.


Hope this helps.

Don
 
Hey Don; do you publish the "Flats" method....

Don at Airflow said:
From our manual:


INSTALLATION OF PIPE THREAD AND O-RING FITTINGS


The torque values listed are recommended values, these DO NOT supersede any published airframe/engine manufacture publication.

PIPE THREAD FITTINGS

? DO NOT under any circumstance use Teflon tape.

?Approved sealants are Permatex Thread Sealant #14 or Loctite 565 PST.

Recommended Pipe Thread Torque Values

? Torque 1/8? NPT fittings to 45 ? 65 inch pounds.
? Torque 1/4? NPT fittings to 70 ? 110 inch pounds.
? Torque 3/8? NPT fittings to 95 ? 135 inch pounds.
? Torque 1/2? NPT fittings to 110 ? 140 inch pounds.


O-RING FITTINGS and AN FITTINGS

?DO NOT under any circumstance use pipe thread sealant, ?Gas Tite? or Teflon tape on O-ring fittings. No sealant of any kind is required on flared fittings or B-Nuts.

? Apply a film of motor oil to the O-ring before installing the fitting.

Recommended O-Ring and Flared Fitting Torque Values

?#4 Plugs 20?25 in-lbs., #4 Hose B-Nut 25-35 in-lbs., #4 Bulkhead Nut 45-50 in-lbs.

?#6 Plugs 30?35 in-lbs., #6 Hose B-Nut 30-40 in-lbs., #6 Bulkhead Nut 90-100 in-lbs.

?#8 Plugs 45?50 in-lbs., #8 Hose B-Nut 60-80 in-lbs., #8 Bulkhead Nut 150-250 in-lbs.

?#10 Plugs 60?65 in-lbs., #10 Hose B-Nut 100-150 in-lbs., #10 Bulkhead Nut 200-350 in-lbs

? If the fitting leaks around the O-ring seat, replace the O-ring, inspect the O-ring port for scratches or nicks.

? If fitting leaks around flare fittings inspect the flare for scratches, or improper flare. Inspect the AN fitting for nicks or dents on the taper of the fitting where the flare seats.


Hope this helps.

Don
Click to expand...

The reason I ask is that I find that it can be nearly impossible to get to many of the fittings with a crows foot and torque wrench. I have also found that among the many less mechanically inclined, the risk of "mis-handling" a torque wrench are pretty good, leading to more harm than good.
 
Aeroquip?

Don -

Is the manual you are referring to for the aeroquip fittings/hoses? In researching the hoses I have, they are the stock Van's hoses in the FWF kit, which I believe are all Aeroquip. Let me know. Still trying to nail this down.
 
Flat method

We recommend that the alternative for injector nozzle line B-nuts to be torqued to 25 in-lbs, or finger tight plus 1/2 flat. I do not have the recommended method to do this with AN B-nuts. I guess if you were curious, you could torque the B-nut on a sample fitting where you could get a torque wench on it to establish "the feel" then proceed with the same "feel" on the actual connection you were tightening.

The torques listed above are for hose and tube B-nuts.

Don
 
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