fuel pipe connection to rail

[geoff]

the fuel feed from the pump enters the engine bay and then connects to the fuel rail via a rubber hose.
This hose has a crimped on union on one end but then fits over a barbed metal pipe on the engine end.
I have reduced the length of this hose and need to re terminate it over the barbed tube, however it has been mentioned that fixing this tube over the barbes needs to be done using high pressure fittings.
Is this really necessary - and what are they ?
regards
geoff

[tima01864]

Once you cut off the old line and pressure cup. A FI clamp will do. If I am understanding you correctly

[rridge]

https://autoricambi.us/fuel-injection-hose-clamp/

[spider2081]

This hose has a crimped on union on one end

I think the fuel pump is capable of out puts close to 100 lbs, however the fuel pressure regulator keeps the pressure below 35 psi.
I'm not sure what is considered "high" but the original fuel rail from the factory used a cupped washer at the base of the barbed fitting. The hose was pushed all the way onto the barb with pressure on the cupped washer. I think the washer prevented the hose's end from expanding. Originally there was no crimped fittings or clamps on the hoses.
I find installing hoses on the barbs challenging, I grease the barbs and the inside of the hose, Then I heat the hose with a hot air gun. Then in one quick motion I push the hose all t he way onto the barb and into the cupped washer. I do them off of the car with the rail on a solid surface so all the force on the hose is used.
Adding clamps certainly gives more confidence there will not be leaks.

In re-reading the original post I realized the factory fuel return hose from the pressure regulator has a "pinch clamp" on the hose where it mated to it's metal line. Replacing the pinch clamp with a fuel hose clamp is a good choice.

[RRoller123]

+1, that does the trick, doesn't cut into the hose. Might want to consider replacing with new FI hose. I put a new one in that was about half a foot longer than needed, so every time it comes off, it can just be cut away and there is plenty left for the new connection. The excess is in a loop and doesn't interfere with anything. Been removed at least 4 times over the past few years, lol probably more.

[geoff]

that's all been very helpful - thanks
geoff

[RRoller123]

Our FI systems run at about 35-37 psi or thereabouts, so make sure that you get FI rated hose. It comes in various grades. My local auto parts shop only had 200 psi grade, a little overkill, and it doesn't bend quite as easily, but no harm, no foul, and plenty of safety margin. Just be sure to get hose rated for well above 36 psi for a good safety margin, and only use FI hose clamps.

It is the same with the (4) short pieces that connect the (4) injectors to the rail. And the piece that connects the CSI Injector. Use FI clamps and FI hose there.

There aren't that many true safety issues with these cars, but spraying high pressure gasoline all over a hot engine would sure make that short list!

[geoff]

I am using TWO FI hose clamps in series however there is still some leakage. I am wondering if the hose needs to be replaced.
Problem is I don't know if they are available - I don't see them at Vick's

[RRoller123]

It is standard 5/16" (0.3125") Fuel Injection hose, available at any auto parts store, used in place of the metric 8mm (0.3149") hose. The 5/16" is fine. Just get the right pressure rating.

[geoff]

yes RRoller, getting hose is no problem. The problem is that in order to keep as much originality as possible, the hose must have a tapered threaded fitting at one end - the end that attatches to the solid line which enters the engine bay.

[RRoller123]

Originality is good! But it is also VERY rare around here, maybe too rare? Who knows. Good luck!

[tima01864]

I don't get it? The original rubber must be hard by now. The only way to be safe is replace the line. 2081 gave you a good description to keep the compression fitting making it as original as you will ever get.

[TX82FIAT]

I would use 7.5 to 7.9mm Fuel injection hose and not the 8mm with the proper FI clamps shown from Auto Ricambi above. You can always put a barbed in line connector in the engine bay before the fuel rail and replace a small section of hose rather than have a few extra inches of hose cutting away each time you disconnect. I have a section where I can plug an in-line fuel pressure gauge when doing diagnostics because I removed the cold start valve. No leaks. While you are looking at fuel hose take a few minutes and make sure the rubber filler neck that connects the gas tank to the fuel filler hole is in good shape. those tend to deteriorate with the modern gas and a lot of years.

[geoff]

I am not sure we are all talking about the same thing. My car is original and is a 1981 injection car.
The hose has a crimped fitting at one end which via a tapered male thread fits into the solid line entering the engine bay.
The other end was pushed over the barbs and crimped on to the pipe on the engine fuel rail.
I agree that it is time to replace the hose due to its age. but cannot see how to connect a new hose to the solid pipe entering the engine bay which terminates in a femaile tapered thead fitting.

[TX82FIAT]

Are you talking about the need for a fuel line flare nut to barbed connection that serves as a union between the factory metal fuel line coming into the engine bay and the rubber hose that ultimately connects to the fuel rail. You will still need a fuel line clamp on both ends of the rubber hose. I'm not sure it that set up mimics the factory set up but that is what I have used in the past and it has worked fine. Do not recall the thread or type of flare needed on the connector.