Repetitive Fuel Leak 69 Chrysler 300

[MJFUR]

69 Chrysler 300 that was rebuilt to OEM a couple of years ago. New steel fuel lines, new fuel hoses, new OEM style clips, new fuel pump.

After the car sits for a month or so and I start it the fuel lines into and out of the fuel pump leak fuel (flow not drip). It started with the OEM clips and after replacing the hoses and it still leaked I started using the incorrect stainless band clamps. When they started leaking I started to double up on the clamps.

When I use the car more frequently there isn't an issue. Which is weird because the fuel should be sitting in the hoses all of the time. And it only leaks at the pump, not any of the other rubber hose/steel line connections.

After I start the car I check for leaks. When I have a leak I turn the car off, fiddle with the clamps and hoses, re-start the car, no leaks, can drive for how ever many miles I want and return home without any leaks. If I start the car tomorrow or next week there won't be any leaks. If I wait a month or so the leaks reappear.

Hoses are from AutoZone if hose brand makes a difference. Is there a specific hose brand that would be more durable?

And I have not been able to get any of the OEM style clips to NOT leak. How do they restore cars?

Anyone else have this problem?

TIA

 

[CBODY67]

Never have seen that issue. The/any OEM production clamps work fine. I ALWAYS get OEM-level hose by Gates (what used to be Gates Green Stripe, back then), though, to ensure what I get is OEM-level or above.

Just my experiences,
CBODY67

 

[Lefty71]

You can get Oetiker clamps online. Last ones i bought were at NAPA, so maybe try there. Those small worm clamps are garbage. Also, buy upgraded fuel hose, not the plain rubber stuff.

 

[57fury440]

Try using the better clamps that are used for fuel injection lines. Are the hoses the right size? Do they fit nice and snug when you push them on?

 

[Big_John]

69 Chrysler 300 that was rebuilt to OEM a couple of years ago. New steel fuel lines, new fuel hoses, new OEM style clips, new fuel pump.

After the car sits for a month or so and I start it the fuel lines into and out of the fuel pump leak fuel (flow not drip). It started with the OEM clips and after replacing the hoses and it still leaked I started using the incorrect stainless band clamps. When they started leaking I started to double up on the clamps.

When I use the car more frequently there isn't an issue. Which is weird because the fuel should be sitting in the hoses all of the time. And it only leaks at the pump, not any of the other rubber hose/steel line connections.

After I start the car I check for leaks. When I have a leak I turn the car off, fiddle with the clamps and hoses, re-start the car, no leaks, can drive for how ever many miles I want and return home without any leaks. If I start the car tomorrow or next week there won't be any leaks. If I wait a month or so the leaks reappear.

Hoses are from AutoZone if hose brand makes a difference. Is there a specific hose brand that would be more durable?

And I have not been able to get any of the OEM style clips to NOT leak. How do they restore cars?

Anyone else have this problem?

TIA

View attachment 729255

View attachment 729256

Just curious... 5/16" fuel hose? That line from the tank looks like it's squeezed down like when someone has a 3/8" hose on a 5/16" fitting. But it's a picture and hard to tell, so I may be just seeing things.

 

[MJFUR]

You can get Oetiker clamps online. Last ones i bought were at NAPA, so maybe try there. Those small worm clamps are garbage. Also, buy upgraded fuel hose, not the plain rubber stuff.

What is "upgraded" fuel hose compared to "plain" mean? Do those come with glitter? What are you talking about?

 

[MJFUR]

Just curious... 5/16" fuel hose? That line from the tank looks like it's squeezed down like when someone has a 3/8" hose on a 5/16" fitting. But it's a picture and hard to tell, so I may be just seeing things.

I'll have to go and check the size. It may be incorrect but if it is it's also incorrect on the other end which isn't leaking.
It's weird that I don't have any other leaks at any of the other rubber to steel connections.
It's also weird that fuel flows out of both the vacuum side and the pressure side hoses of the fuel pump but only when the engine is running.

 

[carguy300]

I was wondering myself if someone had 3/8 hose on 5/16, agreeing with Big John.

 

[413]

Maybe the pump is leaking and the hoses are the lowest point where your see fuel dripping from?

Those worm drive clamps are the best clamps to use.

 

[57fury440]

Like I said earlier, check the sizes of the hoses. They should be snug without any clamps on them. Someone may have put 3/8" hoses where 5/16" hoses go.

 

[MJFUR]

.

 

[CBODY67]

The best fuel-rated hose will have a reinforcing cord AND be thicker than the less expensive fuel line hoses, by observation. No glitter, just high-quality rubber. Which is why I mentioned the Gates brand.

CBODY67

 

[Lefty71]

What is "upgraded" fuel hose compared to "plain" mean? Do those come with glitter? What are you talking about?

Yes....that is correct. Make sure to ask your jobber for titty sprinkle hose.

 

[MJFUR]

Maybe the pump is leaking and the hoses are the lowest point where your see fuel dripping from?

Those worm drive clamps are the best clamps to use.

You can get Oetiker clamps online. Last ones i bought were at NAPA, so maybe try there. Those small worm clamps are garbage. Also, buy upgraded fuel hose, not the plain rubber stuff.

LOL

FYI - the hose is a GATES. Too late to pull them apart tonight. Mess with it tomorrow or tomorrow-tomorrow or a different tomorrow. Thx

 

[Lefty71]

Those small worm clamps are garbage.

Those worm drive clamps are the best clamps to use.

Gonna have to agree to disagree on that one.....I use a lot of worm clamps, but never ever in the small sizes, especially with fuel. There is simply too much deformation where the body is under the screw..... Oeticker clamps do not have this issue, and can hold back 125# plus with ease, on the proper hose. All joking aside.

 

[CBODY67]

LOL

FYI - the hose is a GATES. Too late to pull them apart tonight. Mess with it tomorrow or tomorrow-tomorrow or a different tomorrow. Thx

Unfortunately, there used to be only the Green Stripe Gates hose. Then in the 1980s, they introduced a "Charter" line of belts and hoses which were not up to the "Green Stripe" level, but looked similar, but were MUCH less expensive. Ask your local auto supply which one you bought so you know.

A friend worked at a private-owned, local auto supply and told me that he sold the crap out of the Gates Charter belts and hoses, for like $2.99 each, back then. When told of the "not lasting as long as the better Gates lines", the customers said they were going to trade the vehicles soon, but they came back the next year wanting another set of what they'd previously bought.

Take care,
CBODY67

 

[Big_John]

t's also weird that fuel flows out of both the vacuum side and the pressure side hoses of the fuel pump but only when the engine is running.

With all the discussion about clamps and hose type, I think everyone is missing this.... That it's leaking on the suction side of the pump.

That would lead me to think it's possibly a problem with the body of the pump. Cracked or bad connection of the nipples to the pump body or even as @413 suggested, the pump is leaking and dripping down.

 

[66/440]

X2 on Gates hoses & belts.

 

[CBODY67]

For good measure, I went online to check what was on the AutoZone website. One roll of Continental brand fuel line hose (formerly Goodyear, I believe) and the rest were "Duralast" branded. Their house-brand hoses MIGHT be made by Gates, BUT that does NOT mean they are the same hose as Gates sells themselves under the Gates brand. BTAIM

It seems that with the advent of OEM fuel injection, its related higher pressures, and varuabke kevels of ethano, the Gates Barricade-brand hose might have replaced the prior "Green Stripe" hoses as their now-premium-level fuel line hoses. Which are rated for something like 100psi working pressure and have an internal "barricade" layer which allows them to be compatible with any level of ethanol in the fuel.

Take care,
CBODY67

 

[413]

Gates has barricade fuel hose and barricade fuel hose for EFI that takes 225 psi. Not necessary for a carbureted vehicle.

The barricade is good for ethanol fuel.

It is not thicker than the other fuel hose, rubber is a bit more dense less pliable. Works good.

I doubt you need 225psi hose with 5-7 psi fuel pressure.

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