Guidance on Hose Change

[Spruce500e]

I have had my 500 for a very long time. When i bought it i was cautioned about a hose running from the block to through the firewall. I dont know what its called but I have the part and can see where its located. Looks like PN1248307696. I was told its prone to failure and there is another hose at back of motor that can suffer from same fate and a must to swap out.

Can someone confirm if this is true and what the other hose would be? I know its a long shot but wanted to ask while Im building my shopping list. I already have the one hose and was thinking bout swapping it when I drain the block and change thermostat wondering if other folks have replaced these hoses. Below is pic of the hose I do have is there another one and is this a critical hose at risk of rupturing in same general area?

 

[gerryvz]

There are two hoses that go from the back of the engine on our cars.

One goes from the rear of the engine to the heat exchanger inside the dashboard area. This is what transfers engine heat in the coolant to the interior of the car. There are two different versions of this hose, depending on if you have an earlier or a later car. By "early car" I mean cars with VIN number ending in 096886 or lower (which would make the "early cars" hose appropriate for cars produced up to the mid-January 1994 time frame).

The early cars' part number is: 124 830 76 96

The later cars' (Feb 1994 & later production) part number is: 124 830 74 96

The other line goes from the back of the engine to the coolant recirculating pump (which circulates coolant to the monovalve under low engine RPM as well as to the heating element inside the windshield washer tank).

The part number for this hose is: 124 830 54 96

Hope this helps.
Cheers,
Gerry

 

[Spruce500e]

Thank you Gerry for prompt reply

 

[samiam44]

Prone to failure??

I know at some point 93 ish the rubber hoses were improved. Maybe those hoses get more stress when engine is on bad motor mounts?

M

 

[Klink]

Prone to failure??

I know at some point 93 ish the rubber hoses were improved. Maybe those hoses get more stress when engine is on bad motor mounts?

M

The material was indeed changed to something hyper durable around that timeframe, but I haven't seen a VIN break point. IIRC, there was a part number change, but I won't have access to that information for a day or so. The bad part numbers used to be shown in the EPC with a "no longer to be used" footnote, and they may still be.

 

[gerryvz]

That notation is not present in my "civilian" EPC - either the MBUSA provided one and also not in the 2013 local one I have on my hard drive.

 

[emerydc8]

Here's a good link on this job. http://www.500eboard.com/forums/showthread.php?t=3254

Last spring the hose on the passenger side of my 95 E420 had rubbed up against the air filter mount stud so much that it sprung a leak. I didn't realize until after I had replaced it that the coolant ran under the plastic cover for the spark plugs and into the #4 cylinder, causing a severe misfire.

If you are going to do the driver's side, I took a picture of where it connects to the pipe that runs across the back of the engine, horizontally. It is much easier to get to if you remove some of the plastic. Even with that removed, you won't be able to see the pipe while you connect the hose to it. You just have to feel for it.