When I changed the head gasket two years ago on my 300SE I replaced all the freeze plugs, except for the psg rear one with the hex screw and it now starts to leak coolant. Found this at pelican parts, is it the right part for the early m103, would think they are all the same? What's the best way to replace it, I can reach it without taking off the exhaust manifold, but I'm afraid the old plug will break when taking it out because of rust. Any pointers on how to tackle this and keep it simple?

https://www.pelicanparts.com/More_Info/1179970230MBZ.htm?pn=117-997-02-30-MBZ&bt=Y&fs=0&SVSVSI=3353&fbclid=IwAR25SL-qju1fW9Mb4gurnQ4wkBQMDOLc_LLV2GhRuMzkjJdK35ZCu4ToSX8

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1979 Black on Black, 300CD (sold), 1990 Black 300SE, Silver 1989 Volvo 780, 1988 300CE (vanished by the hands of a girlfriend), 1992 300CE (Rescue).

If it's just seepage try dropping a couple of Bar's Leaks tablets or liquid into the cooling system . A friend of mine who managed the Viper plant before the DB merger said it was SOP to add a couple of tablet to the Viper cooling system at the plant and most automotive plants did the same.

Duke

It's more than seeping unfortunately. The coolant reservoir was empty after a couple of hours of city driving.

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1979 Black on Black, 300CD (sold), 1990 Black 300SE, Silver 1989 Volvo 780, 1988 300CE (vanished by the hands of a girlfriend), 1992 300CE (Rescue).

Got a new freeze plug from the dealer, unfortunately the correct O-ring needs to come from Germany. Is there anything specific about this MB-ring, or can I just use a generic one from the shelf?

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1979 Black on Black, 300CD (sold), 1990 Black 300SE, Silver 1989 Volvo 780, 1988 300CE (vanished by the hands of a girlfriend), 1992 300CE (Rescue).

Wait for the correct O-ring unless you know what material it is made from and can match it.

Good luck!!!

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"Rudeness is a weak man's imitation of strength" - Eric Hoffer

Makes sense with the coolant and heat from the engine. Thanks!

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1979 Black on Black, 300CD (sold), 1990 Black 300SE, Silver 1989 Volvo 780, 1988 300CE (vanished by the hands of a girlfriend), 1992 300CE (Rescue).

If I was me, any o-ring would do. Put some teflon tape for good measure.

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Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

W124 Keyless remote, PM for details. http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/334620-fs-w124-chasis-keyless-remote-%2450-shipped.html

1 X 2006 CDI
1 x 87 300SDL
1 x 87 300D
1 x 87 300TDT wagon
1 x 83 300D
1 x 84 190D ( 5 sp ) - All R134 converted + keyless entry.

This is the part and its location .pic to follow .

this one

Attached Thumbnails

 

Yep, that's the one.

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1979 Black on Black, 300CD (sold), 1990 Black 300SE, Silver 1989 Volvo 780, 1988 300CE (vanished by the hands of a girlfriend), 1992 300CE (Rescue).

Okay, I have a problem. It's leaking in the inside of the plug and for some reason the hex is rounded, can't get a grip with a 22mm socket, it will slip. What to do now?

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1979 Black on Black, 300CD (sold), 1990 Black 300SE, Silver 1989 Volvo 780, 1988 300CE (vanished by the hands of a girlfriend), 1992 300CE (Rescue).

I've had success epoxying internal hex drivers into rounded fasteners. Did this on a W123 diesel starter bolt and it worked. The epoxy fills the gaps and prevents the hex from slipping.

Good luck!!!

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"Rudeness is a weak man's imitation of strength" - Eric Hoffer

The trick is to use a chisel and start with tight socket on hex and punch it on the outer most lip, use plenty of wd- 40 or other lube eventually loosens it will get distorted , and worse case dremel tool it in half (the plug)with out damaging the block

Thanks for the tips. I have to work a couple of days and will continue Friday again. I report back.

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1979 Black on Black, 300CD (sold), 1990 Black 300SE, Silver 1989 Volvo 780, 1988 300CE (vanished by the hands of a girlfriend), 1992 300CE (Rescue).