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Which fuel hose is biggest problem?

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Old Jun 27, 2018 | 09:59 AM
  #16  
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Default NAPA

It wasn't a NAPA shop, but I did not have that experience. I'm just saying on my model there was no room for error and I couldn't use what they did to my line. It is a very tight fit at the rack.
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Old Jun 27, 2018 | 11:23 AM
  #17  
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I to was thinking about a.correct but not offensive respond. Bottom line is they will all need to be replaced. Mine “looked great” on the outside but were very due when replaced at about 25 years and about 90k. Even a tiny bit of seepage results in a big fire. New hoses are very cheap insurance.
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Old Jun 27, 2018 | 11:40 AM
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I was just wondering if there was a specific one, by location, that would rub or be close to heat that was MOST
likely to create a fire. (understood they all need replacement over time) some of the snarky comments are a bit laughable;
no need, when we are all just trying to gain knowledge. I think its great to learn as much as possible about ANY topic.
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Old Jun 27, 2018 | 11:58 AM
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Amazing.

There is no one
Its not from rubbing
You cant SEE the problem
Its as much ATF as Fuel
You're working on your car, disturbing them(!)
You believe they need replaced, over time (contrary to all evidence and advice)
You trying to gain knowledge

You still want to know which...one.
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Old Jun 27, 2018 | 12:08 PM
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I understand the question, while agreeing that they all have to be renewed. Working on a limited budget on the car, I have had to exercise patience; I would never be able to get a bunch of lines bought or rebuilt past the Minister of Finance, but one or two at a time, yes. Hard lines are worthy of inspecting and renewing too. Lili will be two years with me in November.

I remind myself that I am rebuilding something I want to drive my granddaughter around in, that usually settles any questions of method or services.

James
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Old Jun 27, 2018 | 12:22 PM
  #21  
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As said a few times already. There is not a specific one more prone to bursting, cracking, splitting, heat wearing, leaking. All of them will and at different times. Replace them all and don't worry about it for another 20 years. Over thinking the issue muddles the answer for everyone.
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Old Jun 27, 2018 | 12:22 PM
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Originally Posted by merchauser
I was just wondering if there was a specific one, by location, that would rub or be close to heat that was MOST likely to create a fire.
If we were forced to answer you, I guess the one least likely to fail is the one which connects to the hard line and loops over the passenger valve cover over cylinder #1.
It's out in the open, less heat, doesn't get bumped when messing with many sensors or pulling the MAF like the ones in the rear and front are.
I'm pulling this totally out of thin air since I've never thought about it before. The idea of changing only some of the fuel lines is along the same lines as only buying one or two tires when they are all bald.

So, the other 3 are all a tie. There is zero data to support any one of them failing more or less than another.

Bonus: When replacing the short one in front, is the best time to replace the least likely one to fail since they snake through the same area.

Bottom line: Do them all at once, as everyone has said in this thread.


Sunday I was replacing the lines on a local 86.5. These engines have 3 formed lines, and one which is clamped on with bulk fuel line. I swapped the first 3, pressurized the system to check for leaks. When I reached down to feel the fitting on the "U" line in back, I bumped the original "bulk" line and guess what....it instantly started to leak. There was zero evidence of previous leaking from that hose before I bumped it.
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Old Jun 27, 2018 | 12:26 PM
  #23  
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Delete...no need to pile on. Please change all of them.

Last edited by Captain_Slow; Jul 30, 2018 at 07:43 AM.
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Old Jun 27, 2018 | 12:59 PM
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Originally Posted by Hacker-Pschorr
If we were forced to answer you, I guess the one least likely to fail is the one which connects to the hard line and loops over the passenger valve cover over cylinder #1.
It's out in the open, less heat, doesn't get bumped when messing with many sensors or pulling the MAF like the ones in the rear and front are.
I'm pulling this totally out of thin air since I've never thought about it before. The idea of changing only some of the fuel lines is along the same lines as only buying one or two tires when they are all bald.

So, the other 3 are all a tie. There is zero data to support any one of them failing more or less than another.

Bonus: When replacing the short one in front, is the best time to replace the least likely one to fail since they snake through the same area.

Bottom line: Do them all at once, as everyone has said in this thread.


Sunday I was replacing the lines on a local 86.5. These engines have 3 formed lines, and one which is clamped on with bulk fuel line. I swapped the first 3, pressurized the system to check for leaks. When I reached down to feel the fitting on the "U" line in back, I bumped the original "bulk" line and guess what....it instantly started to leak. There was zero evidence of previous leaking from that hose before I bumped it.

I would say, the one at the tank.

The one up front after a few months of hands around it now...is pretty high on the list now...if someone took the route of betting against the odds that "there is a one".
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Old Jun 27, 2018 | 01:14 PM
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RE: stats on where they start, Greg Brown and Mark Anderson are the fire car kings. There are at least two burn cars at Greg's _right now_.

But at Greg's there's usually enough car left to tell where it started; Mark's, notsomuch...

Greg's:


Mark's:
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Old Jun 27, 2018 | 01:26 PM
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Originally Posted by Ed Petry


Hi Greg,

I am having a bit of trouble finding the Porsche hoses on PET. What are the part numbers for the mentioned Porsche parts (for an ‘81 928). I don’t think my vehicle has the cooler. Is that correct?
Thanks in advance.

Early cars are completely different and need completely different hoses/lines.

USA model or Euro?
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Old Jun 27, 2018 | 01:43 PM
  #27  
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Merchauser, the answers just reflect the fact that it doesn't seem to make sense to ask the question, if you know they all need replacing.

Originally Posted by Landseer
One scary thing I saw on a high mileage S4 was degradation of insulation on the heavy positive cable that feeds the antilock brakes. This cable passed behind the power steering reservoir and in close proximity with power steering hoses. The insulation was breaking off in pieces with contact. I don't know if this is an anomaly for that particular car or more prevalent but it was really an eye opener.
^^^ Agree here 100%. And if I am not mistaken the line is for some reason unfused!!!! Big danger there!!
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Old Jun 27, 2018 | 02:03 PM
  #28  
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You can count me as one who replaced all the rubber flammable fluid carrying hoses at once. For those reading along that have 16V cars, don't forget the little 50mm rubber hoses from the fuel rail to the injectors. All 8 of mine were in this same condition; dry rotted.

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Old Jun 27, 2018 | 02:24 PM
  #29  
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Originally Posted by merchauser
I was just wondering if there was a specific one, by location, that would rub or be close to heat that was MOST
likely to create a fire. (understood they all need replacement over time) some of the snarky comments are a bit laughable;
no need, when we are all just trying to gain knowledge. I think its great to learn as much as possible about ANY topic.
The problem is that while there may be one that is most vulnerable, the fact is that they are all vulnerable.

And it's not 'rub' or 'heat' that causes failure, it's flex and age.
The outer sheath is just a protective coating. Unless it rubs all the way through, any damage to it is simply cosmetic. The structural part of the hose is inside. Invisible. And even if you could see it, the weakness wouldn't be apparent.

The first sign of a weak hose is usually smoke & flames coming up from the engine.

Originally Posted by Hymodyne
I understand the question, while agreeing that they all have to be renewed. Working on a limited budget on the car, I have had to exercise patience; I would never be able to get a bunch of lines bought or rebuilt past the Minister of Finance, but one or two at a time, yes. Hard lines are worthy of inspecting and renewing too. Lili will be two years with me in November.

I remind myself that I am rebuilding something I want to drive my granddaughter around in, that usually settles any questions of method or services.

James
I get that there are limits to budgets, and real financial difficulties.

But does the "MoF" understand the financial implications of a catastrophic fire?

But this is one area that is deferred 'at your peril'. This is not speculative or theoretical.
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Old Jun 27, 2018 | 04:02 PM
  #30  
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Originally Posted by Hymodyne
I understand the question, while agreeing that they all have to be renewed. Working on a limited budget on the car, I have had to exercise patience; I would never be able to get a bunch of lines bought or rebuilt past the Minister of Finance, but one or two at a time, yes. Hard lines are worthy of inspecting and renewing too. Lili will be two years with me in November.

I remind myself that I am rebuilding something I want to drive my granddaughter around in, that usually settles any questions of method or services.

James
The late model cars have fuel lines that are plastic pushed over barbs made for plastic hose, which carries all of the actual fuel and handles all of the pressure. The outer rubber covering is simply a protective layer for abrasion. The problem is that the plastic line becomes brittle with age, which makes the plastic prone to fracturing. The issue with replacing the plastic with rubber is that the barbs to retain the plastic are very sharp and can cut the rubber hose. Not a recommended thing to do.

Your '79 (in the front of the car) had a rubber return line, with fittings that accepted rubber hose. Rebuilding that line is fine. The pressure line in the front should have been a plastic line with a rubber outer covering...just like the late model lines. Same as on the late model lines, crimping or clamping rubber hose over those barbs is "asking" for problems (especially with the pressure and volume of the CIS fuel pumps.)

The same issue is true for some of the rear fuel lines in your early car, although a leak is less problematic in the rear, due to a lack of sparks back there.

I'd keep my granddaughter/other slower reacting people out of the car, until that problem is fixed.
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