TPI86TA

I was wondering if the brass compression fitting that you get from the hardware store, are capable and safe for handling high pressure fuel? Or does anyone have any other suggestions? Thanks...Al in NJ.

dennisbernal91z

iTrader: (2)

I would suggest against them. They are not really rated for fuel lines like that.

Tell us what you need to replace and we will tell you the best way to do that.

jv9999

iTrader: (1)

Compression fittings are fine for fuel lines. Dorman sells a kit with 18" of fuel line and a compression fitting. Advance sells them and so does Rock: http://www.rockauto.com/catalog/rafr...0&a=FR42-55180

TPI86TA

I need to replace a section of the high pressure line going to the fuel pump by the tank. Thanks...Al

Guest

It will be fine, just make sure the line isnt bent or damaged where the ferrules are for the fitting.

Contrary to the statement above, compression fittings can more than easily handle the paltry 50ish PSI of a TPI car.

dennisbernal91z

iTrader: (2)

I didn't really mean that they can't handle the pressure. I just thought of taking them on and off. I always need to do that when working by my carb and I wouldn't want to take comp fittings on and off. They are not the best sealers after being taken on and off a few times.

If it is something back there, then I guess fine. Just don't get pissed when you get a small leak due to the flare not being just right on the compression fitting. I personally don't like that stuff, I only use -AN or o-ringed fittings unless forced not to.


I didn't mean to put my personal opinion into the rating of the fitting. My bad.

Vader

AN type fittings are designed for a maximum of about 2,000 PSI (depending upon size. Compression sleeve fittings can be designed for 15,000 PSI (I've used Parker fittings rated at 20,000 on hydraulic test stands). Even the hardware store variety compression sleeve fittings are usually rated at 250 PSI WOG working pressure. I would caution against using any brass/bronze fittings when they might be exposed to methanol, however. It would be safest to use carbon steel or SS for alcohol fuels.

Supervisor42

My :
They are MUCH better than the old "piece of hose and 2 clamps" repair.
It can be difficult to find the 5/16" tube size fittings. If everything is 1/4" or 3/8" it's no problem.
The reason that you don't see brass compression fittings on recently produced equipment is its poor resistance to vibration.
The compression sleeve will lose its "tightness" on the tube especially with a "twisting" type of vibration. This is why you hear stories of having to retighten them to stop nusiance leaks.
That said, they were used for years and years and are much better against a "blow-out" type of failure that can happen with the hose and clamp setup.
This is important when it's a fuel line...

TPI86TA

Does anyone think maybe the compression fitting with a little thread locker might help? Thanks

dennisbernal91z

iTrader: (2)

That won't do anything. The threads are not what get loose.

This is why I opted for you not to use them in the first place. Explain again why you want to use them soo bad?

The best bet, in my eyes, would be to cut off whatever fitting is on there, slap on a double flare then a flare to AN adapter. Then use nice AN fittings. There is a reason why they are used in racing.

Apeiron

Mostly because they were cheap military surplus after WWII. Since then, it's just been inertia.

Silver87

I wouldn't use them just because I have seen so many of them leak water under a pressure of 30-60psi. Seems everytime I use compression fittings, I end up with one that leaks and have to cut off the ferrule and start over. Common brass compression fittings are meant to be used on copper which is very soft; the nut pinches down on the ferrule (the brass ring) and causes it to compress the copper under it and if all is right in heaven and the stars line up just right, it seals and you have no leak. If you move it after it's sealed it likely will leak. So you won't see any hardware compression fittings on my ride. Now the fittings meant for fuel line is another story.

dennisbernal91z

iTrader: (2)

Momentum or not, they are used. Pretty sure if a new engine block that requaired some strange parts came out, pro racers would use it if it were better regardless of the "momentum" that their current setups might have had.

What I am trying to say is that momentum can drive an uninformed market, but not many many many pro racing teams. They do what they see as being best. Thats why high dollar builds use them too. They work. Thats as clear as I can get. Easiest to use and service. Anything else is just hurting you in the long run in my eyes.

spina74

iTrader: (5)

Yo al, im from Laurel Springs im a student over at highland high, if u need another fuel line theres a great junkyard for f-bodies not too far from us.

TPI86TA

Cool, thanks a lot guys.Spina, ill send you a pm.

89rs305-DP

Ha i have a compression fitting on my rear brake lines, NEVER LEAKED. I need to replace my fuel filter soon and i have to cut the fuel line because i cant get the fuel filter to unscrew, and i will be using compression fittings on that too. I havent had a problem with them

jv9999

iTrader: (1)

A compression fitting on a brake line is just crazy unsafe. The first time you REALLY stomp on that pedal it's liable to let loose on you. Brake line pressure can go well over 1000psi. I'd replace that line before I drove the car again.

89rs305-DP

I have been driving it like that for several months now. Even with hard braking it hasnt leaked. Ive heard of many people (and personally know several) using compression fittings on their brake lines. Its not as uncommon as you think. Yea, i agree that it would be safer to replace the whole line, but that wasnt an option for me at the time. Maybe someday ill get around to it. And even if i did fail, id still have my front brakes. I was actually driving around for quite a while with just front brakes with no problems before i repaired my rear lines

Gumby

Steel braided rubber fuel line and double hose clamps on each end have held just fine on mine for many years now..............

Awesome-X

I use compression fittings on my brake lines, there are 2 on my trans am and 1 on the maro. They work great, and the line tends to burst before anything ever happens with the compression fitting. We use them all the time at the shop I work at.

redcorvette

Where I live compression fittings are illegal on brake lines.
There is a difference between quality compression fittings assembled correctly and incorrectly assembled or cheap fittings.
When you take the Swagelok fitting assembly training your test is to assemble a loop of tubing with several fittings. It is pressurized with liquid until it fails. If you assembled the fittings correctly the tubing always splits first, in a straight section since the bends made with a tubing bender work harden the tubing making it a little stronger.

89rs305-DP

See? They work great. I never had a problem with them. People do it all the time

I think they are illegal in most places lol