|
|
|
#1
|
|||
|
|||
Proper Fuel Hose Inner Diameter
I want to replace my fuel hoses with some of the transparent Tygon type style. With the regular black auto parts store stuff I use 5/16 with a clamp, but it does fit a little loose. If I am using no clamp with the Tygon stuff, should I go down to maybe 1/4 ID? Thanks.
__________________
1993 300d - Von Strudel 1987 190e (RIP) - Duke 1983 230e (sold) - Helga 1982 240d (sold) - Igor 1973 280 (sold and missed ) |
#2
|
||||
|
||||
Assuming you're talking about the rubber fuel hose to the lift pump and return? Original size is 7mm which is just a hair smaller than 5/16". A lot of people use 5/16, I had bad luck with air ingress when I tried it and ordered the correct 7mm size and have had 0 issues since.
__________________
Current stable: 1995 E320 149K (Nancy) 1983 500SL 120K (SLoL) Black Sheep: 1985 524TD 167K (TotalDumpster™) Gone but not forgotten: 1986 300SDL (RIP) 1991 350SD 1991 560SEL 1990 560SEL 1986 500SEL Euro (Rusted to nothing at 47K!) |
#3
|
|||
|
|||
Yes, the hose to the lift pump, plus the hose from the IP to the main filter.
I guess 1/4 inch would be ok, since that is only slightly smaller than 7mm.
__________________
1993 300d - Von Strudel 1987 190e (RIP) - Duke 1983 230e (sold) - Helga 1982 240d (sold) - Igor 1973 280 (sold and missed ) |
#4
|
|||
|
|||
1/4 inch works fine for me.
__________________
1973 220D ~135k Mi 1979 Ford F100 300 I6 - 225k Mi |
#5
|
|||
|
|||
Thank you, I'll go for 1/4.
__________________
1993 300d - Von Strudel 1987 190e (RIP) - Duke 1983 230e (sold) - Helga 1982 240d (sold) - Igor 1973 280 (sold and missed ) Last edited by 903hblue; 01-12-2018 at 12:34 PM. |
#6
|
||||
|
||||
Which car is this on? Is this on the '93? If so, you might want to consider sticking with the correct size hose. The lift pump on the 60x engines moves quite a lot more volume than the one fitted to the 61x engines and it is known for causing vapor bubbles in the fuel when used with smaller diameter hoses (too high of suction pressure will cause vapor bubbles in diesel). It's a controversial subject, but some folks claim that the fuel lines used in the Mercedes were less than that specified by Bosch and marginal to begin with.
__________________
Current stable: 1995 E320 149K (Nancy) 1983 500SL 120K (SLoL) Black Sheep: 1985 524TD 167K (TotalDumpster™) Gone but not forgotten: 1986 300SDL (RIP) 1991 350SD 1991 560SEL 1990 560SEL 1986 500SEL Euro (Rusted to nothing at 47K!) |
#7
|
|||
|
|||
Thanks for all the info Diseasel! Yes, this is for the 93, the only benz I currently have.
Wow, that's very interesting and makes a lot of sense. Maybe I will get the factory size for the line to the lift pump and do the rest 1/4 inch Tygon.
__________________
1993 300d - Von Strudel 1987 190e (RIP) - Duke 1983 230e (sold) - Helga 1982 240d (sold) - Igor 1973 280 (sold and missed ) |
#8
|
||||
|
||||
On W123s a whole buch of us use 5/16" hose on the fuel inlet. Never had air in the line issues since I used it since 2007. In fact the same hose is on the Car and working fine.
Of course I used clamps.
__________________
84 300D, 82 Volvo 244Gl Diesel |
#9
|
|||
|
|||
Read up on Tygon. I recall that people who tried it for the small injector over-flow hoses found it didn't last a year. Viton is the best alternative for that (instead of M-B woven type), but you won't find Viton large enough. I used Goodyear Barricade (NAPA), stamped "bio-diesel" at the lift pump in my W123. Probably 5/16", but could be 1/4". I used fuel-injection style clamps, though M-B screw ones should work.
__________________
1984 & 1985 CA 300D's 1964 & 65 Mopar's - Valiant, Dart, Newport 1996 & 2002 Chrysler minivans |
#10
|
|||
|
|||
The real stuff is awfully cheap. Why on earth would you not use it?
|
#11
|
||||
|
||||
Quote:
Are the same hose diameters that are used on the 617 cars correct for the 603, and particularly the later W140 603? I’d be curious about the lines that connect the prefilter and the hard lines, as well as the lines that go between the injectors… Thanks!!
__________________
Current Diesels: 1981 240D (73K) 1982 300CD (169k) 1985 190D (169k) 1991 350SD (113k) 1991 350SD (206k) 1991 300D (228k) 1993 300SD (291k) 1993 300D 2.5T (338k) 1996 Dodge Ram CTD (442k) 1996 Dodge Ram CTD (265k) Past Diesels: 1983 300D (228K) 1985 300D (233K) |
#12
|
||||
|
||||
Clear Fuel Hose
Can't you google / Amazon /E-Bay the correct size in Metric ? .
I don't know of there's clear metric hose out there but it's definitely worth looking for . 1/4" is too small I.D. .
__________________
-Nate 1982 240D 408,XXX miles Ignorance is the mother of suspicion and fear is the father I did then what I knew how to do ~ now that I know better I do better |
#13
|
|||
|
|||
Not sure, but I suspect the clear fuel hose that M-B used is nylon. Many rubbers and plastics don't stand up to diesel, and especially bio-diesel. I saw where one guy used PEX plastic tubing (Home Depot), but it is stiff. As I stated, 5/16" ID hose fit for me (=7.9 mmID). I used Goodyear Barricade, which I think has a Viton liner (hence the name).
__________________
1984 & 1985 CA 300D's 1964 & 65 Mopar's - Valiant, Dart, Newport 1996 & 2002 Chrysler minivans |
#14
|
||||
|
||||
Quote:
__________________
84 300D, 82 Volvo 244Gl Diesel |
#15
|
|||
|
|||
|
Bookmarks |
|
|