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Topic: Fuel lines to engine and genny need replaced? (Read 590 times) previous topic - next topic

Fuel lines to engine and genny need replaced?

All original as far as I know from 1996. No leaks. Any ideas if I should be concerned? Coach was in Colorado summer and Tucson winter, pretty much NO rust anywhere. Any costs idea if and when I have them replaced?
Thanks
1996 U295-36, Cummins 300hp, 8.3. Build number 4864. Vin number 1F97D536XTNO54271. Purchased October 31, 2019.

Re: Fuel lines to engine and genny need replaced?

Reply #1 –
This subject has been exhaustively discussed many times on this Forum.

For general questions of this sort, might I suggest that you first try the Forum Search function?  It is a powerful tool.

Simply enter "fuel line replacement" in the box.  To see the most recent threads, set "Search Order" to:  Most recent topics first.  When I just did this I got 8 pages of hits.  Reading prior threads will most likely answer your question, plus you will learn a lot about your coach fuel system.

https://www.foreforums.com/index.php?action=search
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Fuel lines to engine and genny need replaced?

Reply #2 –
I'm sure there is differing opinions, but my coach is a 99 and fuel lines are in good condition.  I will wait until they need replacing.
Jerry & Nanci
1999 U270 34'WTFI
2011 Malibu
A smart man knows what to say, a wise man knows when to say it.

Re: Fuel lines to engine and genny need replaced?

Reply #3 –
I agree with Jerry (Reply #2)

However I just had all my fuel lines replaced last summer at MoT.  My generator fuel line definitely had an air leak.  Since the fuel tank would have to be partially pulled out to replace the generator fuel line, I decided to have all fuel lines replaced at that time.  The total price was about two coach bucks ($2,000). 

As it turned out, there was a splice in the generator fuel line that had been made by the previous owner.  I had not known of the splice which was way up above and behind the front axle.  I am pretty sure the air leak originated at the splice.  All the removed lines appeared to be in decent shape. 

I wish I had found the splice and saved myself two grand. 

Richard
Jan & Richard Witt
1999 U-320  36ft WTFE
Build Number: 5478 Motorcade: 16599
2011 Jeep Wrangler Unlimited w/Air Force One
Jan: NO5U, Richard:KA5RIW
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Re: Fuel lines to engine and genny need replaced?

Reply #4 –
I had a similar situation with a splice and it was definitely the air source. PO used 3/8 hose and 5/16 fittings.
40ft 1997 U320

Re: Fuel lines to engine and genny need replaced?

Reply #5 –
Richard,
Our 99' fuel lines were replaced in 2014 (about $2k at FOT). The generator fuel supply was the canary in the coal mine... the removed fuel lines looked to be in good shape. That is, until you took a really close look with a magnifying instrument of some kind. When bending it in a small radius, I could see microscopic cracks wherever I looked. I think the only way to be sure would be to put a vacuum on the line and see how well it holds. Just not worth the hassle to have the air leaks get bad when you are either not in a place to get the work done. As you no doubt know, aged out fuel lines on the supply side will always let air in before you see fuel leaking out. This may seem counter intuitive to folks new to these coaches, but as all the high pressure happens after the fuel injection pump after which the fuel is contained in preformed steel tubing, it does make sense. Of course, sometimes the steel lines can rust or the sealing washers at the banjo bolts can start leaking, and that can be a deadly fire hazard. Fortunately, that does not seem to be a common issue, unlike the rubber hose used between tank and the lift pump.
Don
Quote from: Jan & Richard –

As it turned out, there was a splice in the generator fuel line that had been made by the previous owner.  I had not known of the splice which was way up above and behind the front axle.  I am pretty sure the air leak originated at the splice.  All the removed lines appeared to be in decent shape. 

I wish I had found the splice and saved myself two grand. 

Richard
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Don & Tys
1999 U270 3602 WTFE #5402
Xtreme Stage 1 w/Headlight, Step Conversion, etc.
2009 Honda Fit Sport with Navi
Freedom is NOT "just another word for nothing left to lose"... with apologies to Kris Kristofferson

Re: Fuel lines to engine and genny need replaced?

Reply #6 –
Like Don's our coach only was pulling air at the generator. After changing all my fuel lines, the cracks at the fittings were obvious and it was just a matter of time before the engine would suck air. Also after reading about the changes in diesel over the last 20 years I wanted lines to be compatible with current fuel. It is a DIY job if you have room and time. Not rocket science.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Fuel lines to engine and genny need replaced?

Reply #7 –
Jerry the ULSD fuel cracks rubber fuel lines.  You have rubber fuel lines.  Not if but when.  If I parked downhill the engine lost prime and I had to use the Winn manual pump to get the motor to run.  Full tank.  Tank up hill.  Not as noticeable.

Hopefully your damaged lines do not leave you stranded somewhere.

Plus replaced the leaking Winn.  Round file equipment
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: Fuel lines to engine and genny need replaced?

Reply #8 –
Good stuff. It all works great, I'll pass this year.
1996 U295-36, Cummins 300hp, 8.3. Build number 4864. Vin number 1F97D536XTNO54271. Purchased October 31, 2019.
 

Re: Fuel lines to engine and genny need replaced?

Reply #9 –
When and if you choose to do it, search the forum.
My cost was several hundred bucks.
Not that hard if your tank is almost empty.
'99 U320 40 WTFE
Build #5462,
1500 Watts Solar 600 amp Victron lithium
2012 Jeep Grand Cherokee Overland Hemi
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Retired