Need help identifying a hose leaking what I think is coolant ‘80 300SD

[avantbenz]

While under my hood trying to isolate a rattle from my newly installed Meyle air cleaner housing bracket I noticed a steady leak of what looked like coolant. I checked the coolant reservoir and it was running low so that further indicated it was coolant.

Can anyone please help me figure out what hose this is so I can order and install a new one? Thank you for your patience with the newbie. :-)

Link to picture: https://imgur.com/gallery/kmmer5f

I think it's somehow connected to the servo (a/c doesn't work in my car at all but that's a whole 'nother post and potential diagnosis).

Also, has anyone had any trouble with the meyle air cleaner housing bracket and noise? Everything has been tightened - twice - and I used locking nuts and rubber mounts from Ken's MercedesSource but it still rattles during idle and its driving me crazy. Link to rattle video: https://youtu.be/D9Q3XPldSCk

Thanks for help in advance.

[Squiggle Dog]

I think the leaking hose is the one going from the servo and then through the firewall to the heater core. If so, the hose is part number 1168310994. It looks like your servo is cracked, though, so that could be a source of coolant leaks.

I'm not sure on the air cleaner rattling, but it looks like your engine has a cyclonic oil separator in the air cleaner. You might check the oil drain pipe underneath the air cleaner to see if it's rattling. There is supposed to be an O-ring (part number 0069972645) on the nipple that goes into this pipe.

[avantbenz]

I think the leaking hose is the one going from the servo and then through the firewall to the heater core. If so, the hose is part number 1168310994. It looks like your servo is cracked, though, so that could be a source of coolant leaks.

I'm not sure on the air cleaner rattling, but it looks like your engine has a cyclonic oil separator in the air cleaner. You might check the oil drain pipe underneath the air cleaner to see if it's rattling. There is supposed to be an O-ring (part number 0069972645) on the nipple that goes into this pipe.

Thanks for the part numbers - both of them are reasonably priced so I'll pull the trigger on them. Any ideas on how to install the hose?

I'm not sure about rattle - it's driving me crazy trying to figure it out. I tried to take the air cleaner housing off to get at the o-ring to see if it was still there but the locking nuts that came with Ken B.'s kit for the Meyle bracket are giving me a hard time. They're there to lock and that's great but I don't want them to be impossible to get off either. Learning is so fun. :-/

[Squiggle Dog]

I'm ordering new hoses as well, but sadly the lower radiator hose is no longer available. Also, according to a Mercedes parts dealership, the 180 degree hose between the servo and the return pipe going to the engine (1168313394, labeled 314K in the diagram I showed you) has been replaced by part number 1168310994, which is the part number for the hose that goes from the heat exchanger to the servo. How can this be? They are very different in both length and shape. They also claim that the hose going from the bottom of the coolant expansion tank to the bottom of the radiator has been replaced by a part number which is for the expansion tank itself. Here's hoping you get what you need.

In order to replace the hose in question, you first need to remove the aluminum cowl trim where the wiper arms are. Remove the wiper arms and then you have to drill out the metal or plastic rivets at the front of the cowl trim and pull off the cowl trim and the screen underneath. Then you can access the hose where it is clamped to the heat exchanger. It will probably be stuck on there good. You can try twisting the hose to break it free, but the most effective way to loosen it is to carefully pry against the end of the hose with a flatblade screwdriver in a few places until it starts to move and slide forward. It's not an easy task, and what's worse is that the firewall grommet for this hose is no longer available, so don't damage it.

[xaliscomex]

I'm ordering new hoses as well, but sadly the lower radiator hose is no longer available. Also, according to a Mercedes parts dealership, the 180 degree hose between the servo and the return pipe going to the engine (1168313394, labeled 314K in the diagram I showed you) has been replaced by part number 1168310994, which is the part number for the hose that goes from the heat exchanger to the servo. How can this be? They are very different in both length and shape. They also claim that the hose going from the bottom of the coolant expansion tank to the bottom of the radiator has been replaced by a part number which is for the expansion tank itself. Here's hoping you get what you need.

In order to replace the hose in question, you first need to remove the aluminum cowl trim where the wiper arms are. Remove the wiper arms and then you have to drill out the metal or plastic rivets at the front of the cowl trim and pull off the cowl trim and the screen underneath. Then you can access the hose where it is clamped to the heat exchanger. It will probably be stuck on there good. You can try twisting the hose to break it free, but the most effective way to loosen it is to carefully pry against the end of the hose with a flatblade screwdriver in a few places until it starts to move and slide forward. It's not an easy task, and what's worse is that the firewall grommet for this hose is no longer available, so don't damage it.

I read that you removed the rivets that secure the cowl.  Did you use screws when reinstalling the cowl or did you use rivets again?

[Squiggle Dog]

I read that you removed the rivets that secure the cowl.  Did you use screws when reinstalling the cowl or did you use rivets again?

I haven't yet reattached it, but in the past I've purchased plastic rivets from The Classic Center. The originals were steel. When I reattach it, I'm probably going to use screws as I think using rivets is dumb and it discourages regular maintenance of cleaning the cowl.

[daantjie]

Just buy them from amazon, nice and cheap:

https://www.amazon.com/gp/product/B0040CWZKC/ref=oh_aui_detailpage_o00_s00?ie=UTF8&p&sc=1

[raueda1]

I read that you removed the rivets that secure the cowl.  Did you use screws when reinstalling the cowl or did you use rivets again?

I haven't yet reattached it, but in the past I've purchased plastic rivets from The Classic Center. The originals were steel. When I reattach it, I'm probably going to use screws as I think using rivets is dumb and it discourages regular maintenance of cleaning the cowl.

My car had plastic expansion plug rivets with a small core that expands the legs when pushed in.  The plug is a tiny plastic cylinder a little bigger than a pencil lead that gets lost the instant you push the plug through the rivet body to remove the rivet.  I found some pop-rivits, pulled off the flange and cut them to size.  They work perfectly to expand the rivet but have a small head on them so they can be easily pulled out with pliers.  A simple solution that makes life easy the next time.

[Squiggle Dog]

My car had plastic expansion plug rivets with a small core that expands the legs when pushed in.  The plug is a tiny plastic cylinder a little bigger than a pencil lead that gets lost the instant you push the plug through the rivet body to remove the rivet.  I found some pop-rivits, pulled off the flange and cut them to size.  They work perfectly to expand the rivet but have a small head on them so they can be easily pulled out with pliers.  A simple solution that makes life easy the next time.

Clever!

[Squiggle Dog]

Today I received a new hose of the same part number (116 831 09 94). My original hose had part number 116 831 28 94 on it, but it was superseded by the new part number. Putting it up against the old hose, the new hose looks like they cut it too short! I guess it will stretch to reach, but it makes me wonder if there was a mistake.