in the last few years a lot of people have been changing out their fuel
lines. I have been wondering what the over all condition of the old
hoses look like once they were out, especially the parts that are not seen.
was it really necessary.
I am kind of a monkey see monkey do type of person. if I see several people
changing air bags or a particular solenoid or a lift pump or some other vital
part I am likely going to change it out as well, or at least order a spare.
now I am in a tizzy over this king control business. hope someone comes up
with a plug and play solution. anyway, I do have my throttle string ready.
On my coach I had to do a repair on my generator fuel line last winter so this
spring I did my fuel lines.
You mean "monkey see, monkey not stranded by side of road" don't you? Our generator fuel lines had cracks, millions of cracks. I have not see any interior problems with the hoses, nothing in the filter, etc. And we live in California where B5 or B20 is everywhere. When I replaced the generator hose, I just bought a roll of O'Reilly's best and used part of it. We still have a couple of diesel cars, one with almost a half million miles on it with original rubber fuel lines in the engine compartment. Metal lines everywhere else. So far, the fuel lines I've seen that go bad are from the outside in.
I did have a MBZ gas line out of the fuel tank to fuel pump fail from age but the diesel lines are fine.
Waiting for the main fuel lines on our 1993 to start going bad but fine so far. Hopefully, they start going bad at then ends as a compartment carpet soaked in diesel would not be good.
In case you are wondering, copper or galvanized steel fuel lines are not recommended as the diesel may react with the metal. Stainless lines would be fine. Don't know what metal the car makers use but I know our Case tractor has copper and brass in the fuel system. Lots of boats have copper. Our GM bus had steel lines, only a little hose. Seems like madness to run two sets of rubber hoses from the back to the front of the coach.
Pierce
Hi Wayne. We had the lines changed in Reg's old coach last fall. I was able to inspect the old lines along with a tech. The lines in the greater run from the tank to engine and return were in good shape. It was last foot on each end that were cracked. Oregon motorcoach said that they were likely near the time they would have started to suck air into the fuel stream. Of course that is speculation to a degree. But they were defiantly cracked at the ends and the shop was probably not far off the mark.
I know there is a great debate on biodiesel being bad for rubber lines because of alcohol. I could not find one bit of evidence that biodiesel has alcohol in it. I did find a lot of info from fuel makers about how alcohol (methanol specifically) is used in the distillation process of making of biodiesel. But in every case. The manufacturer of said fuels state that the methanol is boiled off to be reused in the distilling process.
Bigdog,
I can't see how it would effect bio-diesel vehicles with rubber lines. Sure has not on ours. Sounds like the dino people starting rumors. Anytime you pump gasoline, you are getting up to 10% ethanol and it does not seem to have any effect on the hoses on older or newer cars. Alcohol does absorb a certain amount of water. Perhaps not a bad thing in fuel systems. Alcohol can effect certain metal fittings in the fuel system when used in a high percentage. Brazil had that problem in the A100 cars.
Pierce
I think when one sees a trend (such as multiple folks with the same year coach breaking down due to fuel lines), it makes sense to be proactive. If you '98 still has the original ones, you are wise to put forth the effort. Many coaches of the 1995-2001 era have had to replace them (and that was recalling the situation a couple of years ago). Better to do it on your timeframe than after a breakdown.
Have not seen the same for 2002 and newer coaches. Not sure if it's just not being reported or if something changed with 2002 and newer regarding the fuel lines or production methods.
Since older Foretravels have not had the fuel hose problem the 1995 to 2001 you note, did Foretravel cheap out on fuel hoses for a while? Not buying any excuses here (from them, not you :D).
Pierce
As for proactive vs reactive fuel line replacement....
The cracks in the lines are generally near the ends, and where they bend. Symptoms are hard/no Start.
I looked at it same way I looked at the steering box replacement. Only a matter of time till they all fail. Did I want to do it on my timetable and at my convenience, or did I want to do it on the fuel lines timetable, and at what level of extra expense and inconvenience.
Being a pilot for 57 years and counting also figured in, dont need an engine failure over something that is a known problem and can be resolved before it is a PROBLEM!!!!
I heard the Biodiesel has methanol (ethanol) and was thus corrosive to rubber fuel lines right here on this forum. That is why I did a little digging and found no truth to that.
Now, Methanol (Ethanol) will in fact dry out rubber and while it might not effect old gasoline cars right away. It was the rubber O-rings & gaskets in carburetors and older fuel injection systems that were at risk over the longer term.
To make biodiesel, about one pound of methanol is used to make 5 lbs of biodiesel. No methanol is left over in the biodiesel and is recycled back to be used in the next batch.
Quote:
"Biodiesel is a renewable fuel produced by the chemical reaction of methanol and vegetable oils or animal fats that is used a replacement or blender for diesel fuel. Biodiesel can be blended with conventional diesel and used in cars, trucks, buses, and farm equipment. Compared to petroleum based fuels, biodiesel demonstrates decreased global warming impacts, reduced emissions, greater energy independence, and a positive impact on domestic economies. HOW IS IT PRODUCED? There are many feedstocks used to make biodiesel. Soybean and recycled cooking oils are used in the United States, rapeseed is commonly used in Europe, while palm oil and jatropha oil are popular biodiesel feedstocks in Asia and Africa. The main reaction for converting oil to biodiesel is called transesterification. The transesterification process reacts methanol with the triglyceride oils contained in vegetable oils, animal fats, or recycled greases, forming fatty acid methyl esters (biodiesel) and glycerin. Some feedstocks must be pretreated before they can go through the transesterification process. In this step, the feedstock is reacted with methanol in the presence of a strong acid catalyst (sulfuric acid), converting the free fatty acids into biodiesel. The remaining triglycerides are converted to biodiesel in the transesterification reaction. The methanol is typically removed after the biodiesel and glycerin have been separated, to prevent the reaction from reversing itself. The methanol is cleaned and recycled back to the beginning of the process. Generally, 20 pounds of methanol is used for every 100 pounds of biodiesel produced."
Pierce
My 1999 had aeroquip fuel lines
That was the very same article I found Pierce.
My fuel lines were fine in the middle 98% but the last foot was sucking air. System was able to manage but it's a matter of time before it damages the pump or your stranded. It's a rubber product, it has a life limit
Scott
My fuel lines on the engine and generator were working fine when I changed them. My thinking was all my tools were at home and plenty of equipment to change them without getting stuck out on the road. Also whether true or not my fuel lines pre dated the new fuel blends and I wanted a product that was designed for the new fuels. I over paid for the Goodyear hoses I bought at a local hose supply house but that was my luck to not have found out on the Forum about buying in bulk online.
Unlikely. Foretravel in that era was not known to cheap out on anything. As you know, in 1995 FT changed over to a bus-front design. Who knows what component, manufacturing, design, etc. changes that caused. Could even have been a process change at the fuel line manufacturer.
I am currently changing the lines of our 1998 U320.
A quick glance showed only a crack in the line that feeds the fuel filter. When I touched that spot with a knife, the line easily separated into two pieces - like a razor blade on a taut rubber band. Numerous visible cracks on the send and return lines, at the ends, on the engine lines. The line from primary filter to the engine was previously replaced - there is a sign.
The engine and generator lines are very stiff. They did not visibly crack when I bent them sharply, but what did the inside do? Aqua Hot lines still seem supple, but will be replaced as well.
I had no symptoms before starting the project - no hard starts, no junk in the filters. I do think my timing is right, after seeing the lines closely. I would rather do them all in my driveway, that splice one in the emergency lane.
I hope this helps.
To bad the fuel lines don't have 4 ft or so laying in the run.. Just pull a couple feet each way cut and reconnect. Then again I can see FT not "wasting" fuel line with each build. Sure makes you want to pull on it and see if you can get enough doesn't it.All that work over a couple feet of bad hose.
Mine had a good bit of slack IIRC
What's wrong with splicing in a piece of hose? It's done all the time. Usually goes bad at the end exposed to heat. Amazon.com : fuel line splice (https://www.amazon.com/fuel-line-splice/s?k=fuel+line+splice)
Pierce
I thought about that, but I like a challenge. Maybe it is an investment in my future too!
If I were to answer the question:
My fuel lines were not bad at the sources of heat. The worst spot was at the fuel filter above my batteries, not cool, but open and ventilated. Second worst was at the tank fittings. The line from the filter to the engine had been replaced, so it may have failed.
On my coach, I had to remove the tank to get to the lines ends at the tank. After that, replacing the lines is a lot easier. Hook new on to old, and feed it through a section at a time.
I was surprised by the dirt, grit and gravel that had worked between the lines under the coach. I could see a line failing from friction. I HAD a line on our previous coach nearly worn through. If my coach dumped the coolant from a failed heater line, I could pinch the line off with a vice-grip, refill with the water hose, and limp along. A diesel leak might be more of a problem - when does that become a hazard? I guess 187 gallons would qualify!
I guess some of the reason to replace the lines is to conform to the community. If/when I sell, "I replaced all of the fuel lines" sounds more conscientious than "I spliced new ends on."
I have not yet finished and refueled, so I may disavow all of that later!
I wasn't talking about a splice. Talking about after pulling the hose out to where hose is good then putting a new end on it and screw into the filter base. I wouldn't trust a splice.Best to replace the lines like everyone is doing but most say all the hose that is protected in the hose Run is "good hose". Maybe good maybe not.
I've had hose go bad on a diesel truck where black crud.. rubber would be in the filter.. The 2 or 3 we had ,the hose wouldn't drip but instead weep and dampen the hose.. We travel to far in the quest to have a good time to patch on the equipment. Money well spent on hoses that are 20 years old even if they are still working.
I had a return line go last winter and spliced in a new section and this spring
I replaced all the fuel lines. I don't want any trouble on the road.
I can't tell if mine have been replaced in its life or not..Looks good but to know for sure of the integrity I would probably need to take loose and bend.. Hate to do that since having no problems but I'm like you and others about being proactive about maintenance.first sign of air I will follow suit and start replacing.
Look for cracks where the fuel line is expanded to go over the fittings at the primary fuel filter.
Blocking at the tank end and using a MityVac is a good way of telling if air is getting in. Probably not worth the effort unless you suspect the hose.
Pierce
Air in a fuel system will show itself real quick in boost and performance. For new diesel owners a dead give away is slow rpm fall immediately after getting off the fuel. Obviously slow to take fuel and respond in conjunction.
May show itself as a smooth idle but looses boost and power going on to the highway or in hills. Starting is worse after sitting overnight. Filter restriction usually starts and idles OK.
Air in the generator is indicated by having to open the "T" handled return valve to get the generator to run right. With the valve open, the fuel pump is able to return the air to the tank. Closed, the fuel pump can't push the air past the overflow/return valve. Not all generators have the hand valve.
Pierce