Fuel supply line removal - stuck on hard line

[epmedia]

seriously, I'd put a torch to that thing. what's the worst that could happen, start a fire? no explosions, no blown up garages, this isn't hollywood. if you disconnect both ends of the line and maybe blow it out with air for good measure what's going to explode? maybe the gas saturated hose might catch fire, so you smother it. put a torch to it.

If a first timer with heat and fuel - not a good idea. I have a first timer story.

Working on the '78 in my Fathers garage...
I had paper towels used to wipe fuel off the fuel pump in my hand for testing, also had a drain pan nearby with a little fuel in it.
I made a spark while testing the fuel pump for movement (it was stuck and had penetrant in it). That spark caught the paper towel on fire, I panicked and tossed the inflamed paper towel too close to the drain pan. Next thing I know - there's a fire under the '78. End result was a white powdery garage and I had some explaining to do. lol

[Been]

[QUOTE="beaucephus;27080681"] How exactly does this work? I don't get it. What kind of snap punch?

image-3325551164.jpg

Automatic Center Punch from McMaster Carr - p/n 3489A13. It's spring loaded and creates a bit of a shock when triggered, which can help with all sorts of stuck fasteners. In the picture, you can see dimples in the hex from the punch. Basically it is a self-hammering punch.

[beaucephus]

Repairing the line also meets my goal of finding what else is broken before ordering more special order parts. I've only spent about 10 hours hands-on with the car in the last 4 months and the rest waiting on parts from Germany just to find out the next thing is also broken. This car has to start and drive soon or it's someone else's problem.

[epmedia]

How exactly does this work? I don't get it. What kind of snap punch?

image-3325551164.jpg

Automatic Center Punch from McMaster Carr - p/n 3489A13. It's spring loaded and creates a bit of a shock when triggered, which can help with all sorts of stuck fasteners. In the picture, you can see dimples in the hex from the punch. Basically it is a self-hammering punch.

That looks like a brilliant idea, I forgot those things existed.
I was picturing trying to use a hammer on the punch when I first read that.

[Tom D]

If a first timer with heat and fuel - not a good idea. I have a first timer story.

Working on the '78 in my Fathers garage...
I had paper towels used to wipe fuel off the fuel pump in my hand for testing, also had a drain pan nearby with a little fuel in it.
I made a spark while testing the fuel pump for movement (it was stuck and had penetrant in it). That spark caught the paper towel on fire, I panicked and tossed the inflamed paper towel too close to the drain pan. Next thing I know - there's a fire under the '78. End result was a white powdery garage and I had some explaining to do. lol

I doubt it was my 'first timer', but when I was in 6th grade I had the brilliant idea of refilling a propane lighter I had with fluid, while sitting on my bed. after emptying a good portion of the can, mostly on me, the bedspread and the floor, I clicked the lighter. talk about an oh shit moment. after spending the next 15 seconds putting out the bedspread and the floor I realized that my hand was still burning. that little brain fade lead me to the emergency room and 2nd degree burns on 50% of the back of my hand. nice!

[epmedia]

Dang Tom! I bet you had some explaining to do too lol.

When I was 4, father explained to me that engine oil on the deck won't catch fire like gasoline does. I was home alone and found some matches. I had just one match left after failed attempts to light that engine oil on fire. Found some newspaper and smeared in that engine oil to use as a big match. The oil soaked newspaper caught fire, I panicked and stuffed the flaming newspaper under the vacant neighbor's carport door that led to their overgrown dry weed infested yard (about 10x10'). Low and behold 30 seconds later there were flames and smoke billowing over the 6' wooden fence. Fortunately we had a garden hose that was hooked up in our 10x10 yard. End result was fire trucks and I was a hero for putting out the fire because I had no idea how that fire started

About 20 years ago, I told my parents what really happened that day. lol

[Tom D]

lol


when I was in 9th grade my father, myself and my 7th grade brother were cleaning the basement. anything that could burn was going into the screenless fireplace. my brother filled a large heavy duty plastic bag with garbage and my father threw it into the fire. a few minutes later while I was standing about 10 feet away and watching it burn the aerosol can inside the plastic bag blew. the explosion was deafening and hurt my ears, but worse was the now molting plastic wrapped around my face. that little brain fade of my brother cost me another trip to the emergency room with 2nd degree burns to 30% of my face and neck. nice!

[epmedia]

dang Tom - your stories are painful! I usually just burn the hair off my arms.
When I was in (about) 9th grade I forgot to tighten one of the fuel lines on a Holley carb after rebuild. Went for a test drive and when I got to the top of the driveway, the puddled fuel on the manifold ignited when it splashed onto the windowed distributor cap. I did not have a firewall installed - I was very lucky. The fuel went POOF right next to the garden hose, just a couple seconds before turning off the engine. It took awhile to put out the gas fire with water. Fortunately only minor damage

[Tom D]

yup they did hurt, but here's the deal, I know something about getting burned and the pain that comes with it. I wouldnt suggest to somebody that they do something that would put them at risk of getting burn. gasoline doesn't burn until turned into a vapor, so if you disconnect the tank and evacuate the line it would be safe to put a torch to. the fuel impregnated hose however will probably burn.

six years ago I underwent radiation therapy, 35 days of extreme radiation. after the first week I had what can be described as a bad sunburn on my neck and upper chest. by the start of the third week they started treating me as a burn victim. by the fourth week it was becoming 2nd degree and they prescribed morphine. by the end of the 6th week I was sporting a tan that took the better part of five years to fade. that event didn't lead to a trip to the hosipital however because I was already there.

be careful with fire guys, it hurts really bad!

[Hatchman]

I just noticed the slip/compression ring is now showing NLA on the realoem!
Find some quick before they're all gone...

Here's a pic I found if it helps:

One of these has to be the culprit

Can probably get a new nut too.

[beaucephus]

It's been a good morning. We went to the hangar to grab some tools and it was too nice out, so this happened.




Then we cut the hard line, removed the clamp and installed 225 PSI Gates FI rated hose. Then the car started for the first time since April. All before lunch. It wouldn't pass a tech inspection, but for now I'm calling it a permanent fix



Thanks all for the help! This is a great thread.

[pommeree]

It's been a good morning. We went to the hangar to grab some tools and it was too nice out, so this happened.

Then we cut the hard line, removed the clamp and installed 225 PSI Gates FI rated hose. Then the car started for the first time since April. All before lunch. It wouldn't pass a tech inspection, but for now I'm calling it a permanent fix

Thanks all for the help! This is a great thread.

Well done! Did you flare the end of the hard tube at all?

[epmedia]

Well done! Did you flare the end of the hard tube at all?

I was curious about that too because mention of 'cut hard line'.
The clamps on the old flex hose should have been cut off to use those barbs, which I'm hoping was done, cannot see in the picture.
Always need hose barbs!

Beaucephus - did you fly to the hangar in that beautiful plane?

[beaucephus]

We didn't flare it, but it did get double clamps. The top used the original barb. The plane is my dad's. We ended up flying a bit instead of just grabbing the tools.

[gusm325]

Great job!
Love to see ingenuity and an alternative to a $70.00 fuel hose, I could be mistaken but I see no reason that would not hold 90 psi.
The a/c hoses are only crimped to the "original barb" and hold well over 200psi.

[beaucephus]

I would not recommend this to anyone that can avoid it. The key takeaway here is that is 5/16 metal line, the other end of the stock hose has a good barb, and you can do lots of stuff between them. Flexible tubing should be minimized, and I just added 2 feet.

[epmedia]

I would not recommend this to anyone that can avoid it. The key takeaway here is that is 5/16 metal line, the other end of the stock hose has a good barb, and you can do lots of stuff between them. Flexible tubing should be minimized, and I just added 2 feet.

Be aware there's always 'about' 10 pounds of weight pulling on that hose when the fuel system is pressurized and fuel is very slippery when it gets between the rubber and steel without a barb to hold it from slipping off. Using two clamps without a barb is better than one clamp, but still not good enough for the long run. So get it proper before you forget about it, please.

*I hope you did not throw away the old hose yet, you can use that lower barb and nut after sourcing the slip ring.

[gusm325]

I understand, I think he cut off the hard line, I'm sure it could be "flared", or are you going to replace the entire run?

[okieflats]

You can't just flare it because it would cut into the line from the inside. You would need to put a bulb type end on it, if you know, so it flares out then back in, so no edge is going to be pressuring the line on the inside.

If it is 90 psi then the blow off force is 7 pounds for a 5/16in or 8mm line. So if it is clamped tight so you can pull hard on it with 10 or more pounds it should be good. Cleanly cut off hard line end smoothed over with no burrs and clamped tight with multiple clamps sounds good.

[Tom D]

I would think that no one in thier right mind would do anything but a double flare on a line that carries fluid, but then again I've seen worse.

I've got a question, where did you get the 7 lbs from?

[epmedia]

I had to find a calculator...
https://www.dixonvalve.com/resources...rce-calculator

Still need a barb for the long run. If it gets slippery the hose will pop off. May happen in two days, or two years, never know.

[okieflats]

Yes double flare would be better to call it. I have fuel lines on other vehicles where the end looks like what is called a bubble end on a brake line. Ex photos: http://www.rtsauto.com/brake-lines-f...-double-flare/

I got 7 pounds blow off force. That is pressure times the cross sectional area. 8 mm or 5/16 inch diameter. And 90 psi.

So 5/16 inch squared times PI divided by 4 then times 90 gives you 6.9 pounds. PI is 3.14. So yes it is about 10 as said before.

[Tom D]

^ so I think what you're trying to say is;

pi times R squared times psi equals hose end force.

- - - Updated - - -

thanks, I have never seen that formula before.

[okieflats]

pi times R squared times psi equals hose end force.

Yes exactly. End force is axial force. Which is perpendicular to the cross section, which is why you use the cross sectional area. And it agrees with the calculator that Robert posted. Area is pi * R squared. Also Area is pi * Diameter squared divided by 4. That is because R = Diameter/2, So R squared = Diameter squared divided by 4.

[epmedia]

I must be getting weak. I estimated 10 pounds based on a 45 psi system that felt like 5 pounds to push and test it's quick connect. lol