Changed out my shutoff valve and all fuel line o-rings with viton today.

The o-rings on the end of the fuel lines which seal to the fuel filter housing (x4) are a different size than the typical fuel line o-ring.

Does anyone know what size those 4 are?

Additionally, has anyone measured the pre-filter o-ring or delivery valve o-rings?

For reference the OM606.962 uses:
shutoff valve 2.5mm x 12mm ID
typical fuel line 2.5mm x 8mm ID

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Terry Allison
N. Calif. & Boca Chica, Panama

09' E320 Bluetec 77k (USA)
09' Hyundai Santa Fe Diesel 48k (S.A.)

Revising the above data for future reference:

1 shutoff valve 2.5mm x 12mm ID
9 fuel line 2.5mm x 8mm ID (1 located at fuel filter housing)
3 fuel filter housing 2.5mm x 10mm ID
1 pre-filter 3mm x 18mm ID

The above applies to the OM606.962. The OM606.912 should have a very similar count.

Would like size of Delivery Valve o-rings (6) if anyone knows.

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Terry Allison
N. Calif. & Boca Chica, Panama

09' E320 Bluetec 77k (USA)
09' Hyundai Santa Fe Diesel 48k (S.A.)

What about the lift pump o-ring size???

I'm impressed there Viton o-rings available for that fit the E300's..... I'm excited

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#dieselFLEET
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'97 E300
'99 E300

Where does one purchase these o-rings?

http://www.mcmaster.com/ ???

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#dieselFLEET
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'97 E300
'99 E300

Correct.

Can't say how long they will last but is hopefully longer than buna.

My last set of OEM 's only lasted 2.5 years.

I don't know about the lift pump or if there is even an o-ring there or not; suspect it may be a gasket as have not seen it discussed on the forum as a source of leaks often.

***edit***

The lift (fuel) pump appears to rely on a gasket for its seal to the side of the IP although there are two o-rings that show up on the EPC inside the pump.

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Terry Allison
N. Calif. & Boca Chica, Panama

09' E320 Bluetec 77k (USA)
09' Hyundai Santa Fe Diesel 48k (S.A.)

If there is a minimum number you need to buy and it's more than you would like to stock, let me know and I'll take some off your hands.

__________________
Len
'59 220S Cabriolet-SOLD and living happily in Malta
'83 240D 351,500 miles original owner-SOLD
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https://sites.google.com/site/mercedesstuff/home
'99 E300 turbo 227,500 miles
'03 SLK320 40,000 miles - gave to my daughter
'14 Smart electric coupe 28,500 miles
'14 Smart electric cabriolet 28,500 miles
'15 Smart electric coupe 28,000 miles

TMAllison, I looked up DV o-ring from a 630.960 and the part number is A0179974148. According to EPC parts search this same part number fits many 601, 602, 603, 616, 617 (but not all) engines. I ordered one and it measures 2x15id.
I am in the process of replacing all my orings with viton ones. It's too bad you can't just buy the amount you need (except from fryerpower $27.50) I had to buy 10 of the 2.5x12 & 3x18 just to get one. Your post says that 9-2.5x8id orings are needed but I can only find where 8 of them go. The part number is A6019970345 and the EPC only shows 8 required, can you show or tell me where these size orings go? Thank you

Attached Thumbnails

 

Been a long time since I wrote that. Haven't had a leak since switching.

I believe the 9th oring went on the fuel canister bolt. #11 or 14 on your diagram.

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Terry Allison
N. Calif. & Boca Chica, Panama

09' E320 Bluetec 77k (USA)
09' Hyundai Santa Fe Diesel 48k (S.A.)

Thanks, Good to hear the oring replacements are holding up. I'll take that one off and measure it (I just replaced fuel filter last month so it shouldn't be too stretched out of shape).

Thanks for this thread - I got my required no. of O rings.. I hope these sizes are also for a OM606.910, I got them in Viton 75 Duro Black color from an O ring supply. Anyone care to chime what to lube them with when installing.. diesel, silicone grease??

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)

I think you'll have a couple of extra's on your .910.

I used some silicone grease on a couple of mine. Seemed fine.

The viton is much stiffer than the buna materail and some of them will be really tight.

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Terry Allison
N. Calif. & Boca Chica, Panama

09' E320 Bluetec 77k (USA)
09' Hyundai Santa Fe Diesel 48k (S.A.)

I am having lots of trouble with the viton rings from mcmaster.

either they shear off on install or don't stay sealed for very long.

one spot in particular keeps letting air in after just a few long cycles - i have replaced it 3 times already.

Does the buna seal up better, even if it doesn't last as long?

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You most likely have a leak @ another source. I have sourced the o-rings from McMaster and not had any issue(s). Check ALL of your lines, hard fuel lines, injector return lines, etc......

The DV threads are very sharp if that is what you are doing. Easy to nick an o-ring. Try lubricating with Diesel or silicone grease possibly.

The Buna is a much softer and pliable material.

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Terry Allison
N. Calif. & Boca Chica, Panama

09' E320 Bluetec 77k (USA)
09' Hyundai Santa Fe Diesel 48k (S.A.)

What do you mean they shear off? Shear as in cut or do you mean slip off? Try soaking them in boiling water before install which softens them a bit.

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