OK, so i have a good deal of diesel experience but it all with marine diesels and they have a slightly different setup for the return line (they dont link the injectors), so coming from the filter to the first injector, then 2, 3, 4 and 5 on the last injector on my car has a blocked off line, where is that line supposed to go? I would assume the filter housing or is it supposed to be blocked off?

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1984 300D Turbo 169k

"Twenty years from now you will be more disappointed by the things you didn't do than by the ones you did. So throw off the bowlines. Sail away from the safe harbor. Catch the trade winds in your sails. Explore. Dream. Discover."
-----Mark Twain

it's supposed to be blocked off.

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1985 300D cali 190K

http://mercedes.thatchermathias.com/mw300d.jpg

alright then that answers that. thanks!

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1984 300D Turbo 169k

"Twenty years from now you will be more disappointed by the things you didn't do than by the ones you did. So throw off the bowlines. Sail away from the safe harbor. Catch the trade winds in your sails. Explore. Dream. Discover."
-----Mark Twain

since all the injectors are identical, they each have two smaller nipples for returns. They cascade one to the other and return via the line off number 1. Number 4 or 5's rear nipple is capped and thats all she wrote.

Yes, the flow out of the injectors is very small. The pressure in those lines is from the relief valve of the injection pump and the bleeder bypass hole in the filter housing.