Clear Fuel Tubing - Page 2 - PeachParts Mercedes-Benz Forum

Beagle · #16 05-05-2009, 04:28 PM

Quote:

Originally Posted by Diesel911

With Rubber hose you only need a Screwdriver and a knife to cut the Rubber Hose to fix it and the Hose is available at any Autoparts store at close to $1 a foot.

So obviously you are not worried about the rubber residue and debris from fuel breaking down your cheap "dollar-a-foot" hose getting into your pump elements and injectors trashing them?? Your gonna need a lot more than a screwdriver and knife and the few $'s you saved to fix that! I hope no-one here is naive enough to take that advice

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Diesel911 · #17 05-05-2009, 05:38 PM

Quote:

Originally Posted by Beagle

So obviously you are not worried about the rubber residue and debris from fuel breaking down your cheap "dollar-a-foot" hose getting into your pump elements and injectors trashing them?? Your gonna need a lot more than a screwdriver and knife and the few $'s you saved to fix that! I hope no-one here is naive enough to take that advice

.

Of course if you do not choose to use it don't. I have it on both my Mercedes and the Volvo Diesel.

The $1 a foot hose is rated for Diesel Fuel and I have seen it in use on many of the other Diesel Engines I have encountered since 1975 and I have never found a Fuel System problem due to rubber particle contamination due to a deteriorating hose (I cannot say the same for deteriorating O-rings or the carless use of Teflon Pipe Sealing Tape).

I also do not remember the older Mercedes Diesels that I encountered a work between 1975-1980 using the plastic tubes or the Thermo King Gen Sets that used Mercedes Engines using plastic Tubing.

The close to a $1 a foot hose made by GoodYear (SAE 30R7) that is also rated for Diesel Fuel- http://www.goodyearep.com/ProductsDetail.aspx?id=10526

You can pay a little more and get this (SAE 30R9; about $3 per foot) which in one of the other threads said it is lined with somethin similar to Viton and rated for Diesel and Bio Diesel Fuels- http://www.goodyearep.com/ProductsDetail.aspx?id=5144

Diesel911 · #18 05-05-2009, 10:52 PM

LOL Tygon makes a lot of different tubing.

http://www.professionalplastics.com/TygonTubingProducts?gclid=CM7m8s_WppoCFQ6jagodoi0J0w

http://www.usplastic.com/catalog/category.asp?catalog_name=USPlastic&Category_Name=29331&Page=1&gclid=COj85KvXppoCFQkzawodOQ780Q&cookie%5Ftest=1

Diesel911 · #19 05-05-2009, 11:12 PM

Strange; I would swear that I read Tygon on one of the plastic hoses but the one I too off of my spare IP has: DIN-78878-PA-TECALAN-79 a arrow and a bunch of widley spaced 2 digit numbers?

Nashvillecat · #20 05-06-2009, 08:31 AM

I purchased some nylon 5/8 tubing from a hydraulics supply store to make a fuel pressure gauge and it seems to have worked pretty well. I used the smallest hose clamps and it did not leak. The only drawback I have seen so far is that the tubing is normally sold in 100 foot lengths. They had some left over.

Oldwolf · #21 05-06-2009, 09:48 AM

What pressure is the clear tubing subjected too?

WD8CDH · #22 05-06-2009, 12:19 PM

Roughly 10 to 20 psi.

Oldwolf · #23 05-12-2009, 10:03 PM

Can metal tubing be used to replace the clear tubing? That way we could just forget about it as a possible failure point.

rcounts · #24 05-13-2009, 11:23 AM

Quote:

Originally Posted by Oldwolf

Can metal tubing be used to replace the clear tubing? That way we could just forget about it as a possible failure point.

Not necessarily. Injector lines are steel and a search will show that having one of them fail due to cracking isn't unheard of. The vibrations these diesels put out can be a real killer - which is why the steel injector lines have the anti-vibration "bridge" clips between lines...

I was wondering about using some clear vinyl tubing like you find at hardware stores (REAL hardware stores - NOT sLowes or Home Creapo). The only possible problem I can see would be excessive heat. Though I have used it for return lines - connected to the injectors - on my 86 F250 and it has held up just fine...

Diesel911 · #25 05-13-2009, 11:39 AM

Quote:

Originally Posted by Oldwolf

Can metal tubing be used to replace the clear tubing? That way we could just forget about it as a possible failure point.

I have seen Copper and Steel Tubing used on other types of Diesel Engines.
However, they use fittings that use tubbing in conjunction with Ferrules or they use fittings in conjunction with flared tubing.
Even these are not trouble free as over time vibration gets to them causing leaks around Ferrules or cracks tubing.

Then there is the problem of how do you connect the metal tubing to the existing Banjos. (A compromise could be to use short lengths of the best quality rubber/viton tubing on each end with metal tubing in between.)

Even though I replaced my plastic tubing with Rubber Hose (if you can get the plastic tubing back on the Banjos tight) the correct Plastic tubing is the best.

WD8CDH · #26 05-13-2009, 02:25 PM

Quote:

Originally Posted by rcounts

I was wondering about using some clear vinyl tubing like you find at hardware stores (REAL hardware stores - NOT sLowes or Home Creapo). The only possible problem I can see would be excessive heat. Though I have used it for return lines - connected to the injectors - on my 86 F250 and it has held up just fine...

The clear vinyl tubing gets hard and brittle. I have had very good success with transparent blue polyurathane tubing with diesel and biodiesel.

rcounts · #27 05-13-2009, 02:53 PM

Quote:

Originally Posted by WD8CDH

The clear vinyl tubing gets hard and brittle. I have had very good success with transparent blue polyurathane tubing with diesel and biodiesel.

LOL, so does the original - which is why this discussion was started in the first place

FWIW, I've had it on the return line of my F250 for about a year and a half and no signs of it getting harder or more brittle. It is yellowing just slightly from the fuel, but at the rate it is going, I'd bet on it lasting at least 10 years.

If it will hold up that long/well, I'd say it it a pretty decent substitute for the original material, and at about a buck to a buck fiddy a foot its cheap enough to replace every 10 years or so...

bart_dood · #28 05-13-2009, 03:53 PM

Quote:

Originally Posted by WD8CDH

The clear vinyl tubing gets hard and brittle. I have had very good success with transparent blue polyurathane tubing with diesel and biodiesel.

Is the polyurethane tubing from home depot or ace hardware? they have clear tubing but I'm not sure what polymer its made from.

Diesel Dan · #29 05-13-2009, 04:12 PM

I've used the "blue" stuff from procycle - but the walls are too thin, and it eventually leaks air due to poor seal and crimping by the hose clamp. I got some thicker clear polyurethane stuff from mcmaster.com, but the jury is still out. I have seen the "yellowing" as well, and one particular stretch of hose broke down and cracked. This hose was in between the lift pump and injector pump. Not sure why it broke down here and not in other places, except perhaps closer proximity to the heat of the engine. I do run 100% biodiesel and straight veggie oil BTW, so my fuel is often over 160 degrees in the hose before it even reaches the engine. The hose I got is rated to 200 degrees. I really do like having translucent hose though. Troubleshooting air leaks is so much easier.

WD8CDH · #30 05-14-2009, 03:52 PM

Quote:

Originally Posted by rcounts

"Originally Posted by WD8CDH
The clear vinyl tubing gets hard and brittle. I have had very good success with transparent blue polyurathane tubing with diesel and biodiesel."

LOL, so does the original - which is why this discussion was started in the first place

FWIW, I've had it on the return line of my F250 for about a year and a half and no signs of it getting harder or more brittle. It is yellowing just slightly from the fuel, but at the rate it is going, I'd bet on it lasting at least 10 years.

If it will hold up that long/well, I'd say it it a pretty decent substitute for the original material, and at about a buck to a buck fiddy a foot its cheap enough to replace every 10 years or so...

True, the origional does get hard but it's not nearly as brittle as hardened PVC.

BTW, I get my polyurathane tubing from McMaster