Bleeding air out of a 300D

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Ninny659
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Bleeding air out of a 300D

Post by Ninny659 » Wed 08 Aug, 2018 6:04 pm

Hi, this may be a silly question, but I was wondering what the best method for bleeding air out of a W123 Engine. I've look around and what I've read seems to indicate that the 300D is self bleeding? I don't know if this is true however.
Thanks

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John Green
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Re: Bleeding air out of a 300D

Post by John Green » Wed 08 Aug, 2018 10:03 pm

Hello and welcome to OZBENZ. Ultimately they are self bleeding, however you can speed things up by loosening the line at the injector end and cranking it over until you see a little fuel come out of the joint, then tighten and away you go.
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mathuisella
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Re: Bleeding air out of a 300D

Post by mathuisella » Thu 09 Aug, 2018 1:04 am

Ah yes, you'll drain a battery or two completely if you try to use the starter to bleed the system without cracking the injector lines at the injector.


If you've just replaced filters do the following


1.Fill the 'main" fuel filter with fuel before you reattach it, rt you'll be using the hand primer pump for years... Hand prime like normal.

2. at the top of the fuel injectors, use a 17mm spanner and just slightly undo the connection of the fuel hardline to the injector. ( yes i know this seems strange, just trust me on this ) You may not be able to do all 5 ( 300D) or all 4 ( 240D ), but do at least 2 or 3.

3. using the starter motor start the engine for about 5 seconds. and then stop.

4. go back to engine back and on those loose injector lines, look on them and see if they are leaking a tiny bit of fuel, If Yes, then tighten them up, if no go back and crank the starter for another 5 seconds.

5. tighten them up as they start to leak fuel and use a bit of 'right foot' when the engine is sputtering " almost running" when you've got all hard lines tightened/closed and in a few moments your engine will growl/purr like normal once the last bit of air bubble has gone through.

if unsure i'm happy to make a quick video on this tomorrow.

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John Green
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Re: Bleeding air out of a 300D

Post by John Green » Thu 09 Aug, 2018 9:41 am

also easier done with two people, one person cranks the engine while the other watches and tightens up the injector line when the fuel shows.
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mathuisella
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Re: Bleeding air out of a 300D

Post by mathuisella » Sat 11 Aug, 2018 5:31 pm

Here's a short playlist i made today for this. hope it helps

https://www.youtube.com/watch?v=_X4geXR ... xo&index=5

Ninny659
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Re: Bleeding air out of a 300D

Post by Ninny659 » Sun 12 Aug, 2018 12:30 pm

Thank you. I got it working with my father. Got it started after a few cranks and the Engine was shaking side to side due to the air. We cracked open the injectors and after all the air was bleed out of the engine it idealed perfectly. Great advice!

mathuisella
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Re: Bleeding air out of a 300D

Post by mathuisella » Sun 12 Aug, 2018 11:47 pm

Ninny659 wrote:
Sun 12 Aug, 2018 12:30 pm
Thank you. I got it working with my father. Got it started after a few cranks and the Engine was shaking side to side due to the air. We cracked open the injectors and after all the air was bleed out of the engine it idealed perfectly. Great advice!


You're most welcome.

I find it easier with pictures/video myself, when working on things like this, so i thought i'd make one to help.

Glad you got it going.

Throw up a few pictures/video of her :D

Always love a W123

P.S if your father is looking for one of his own.... :whistle: ;) i may have one....

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