Water Pump or Something Else? - Page 2 - PeachParts Mercedes-Benz Forum

dkr · #16 08-20-2017, 11:39 AM

I pressurized this morning and there are no leaks. I think my original leak was actually coming out of the gasket on the cylinder head (or lack thereof). There was very little of it left when I pulled everything apart.

Dkr.

tangofox007 · #17 08-20-2017, 11:52 AM

Quote:

Originally Posted by ROLLGUY

The thermostat is located on the engine inbound coolant path, rather than the outbound (like the old American made engines I was used to).

Considering that it's a bypass thermostat, one could argue that it's located on both sides of the "coolant path." In any case, it's the flow on the back side that matters most when it comes to temperature regulation.

ROLLGUY · #18 08-20-2017, 12:03 PM

Quote:

Originally Posted by tangofox007

Considering that it's a bypass thermostat, one could argue that it's located on both sides of the "coolant path." In any case, it's the flow on the back side that matters most when it comes to temperature regulation.

True, but in the context of filling the cooling system, it is not "bypassing", thus both sides of the thermostat need to be filled.

ROLLGUY · #19 08-20-2017, 12:12 PM

Quote:

Originally Posted by tangofox007

Considering that it's a bypass thermostat, one could argue that it's located on both sides of the "coolant path." In any case, it's the flow on the back side that matters most when it comes to temperature regulation.

When I first learned about the thermostat location on these engines, I thought it was weird and backwards (cooled coolant flows past the Tstat into the hot engine, rather than out of the hot engine through the Tstat into the top of the radiator). Evidently this technology is superior, as other manufacturers use it as well.

tangofox007 · #20 08-20-2017, 01:12 PM

Quote:

Originally Posted by ROLLGUY

True, but in the context of filling the cooling system, it is not "bypassing", thus both sides of the thermostat need to be filled.

There is actually a bypass passage in the housing that is intended to enable "self bleeding." Whether said passage is open or not (ie: not obstructed) is another matter.

dkr · #21 08-20-2017, 04:36 PM

I saw on one of the howtos mention replacing the banjo hose for the water pump. I've had several W123s and have never touched it. Can anyone explain to me what that does and whether I should be concerned about it?

Dkr.

Diesel911 · #22 08-20-2017, 09:25 PM

Quote:

Originally Posted by dkr

I saw on one of the howtos mention replacing the banjo hose for the water pump. I've had several W123s and have never touched it. Can anyone explain to me what that does and whether I should be concerned about it?

Dkr.

If someone would post the website that has the Factory Service Manual there is a good description in it as to how the Coolant System works.

When you refill the Coolant System it is notorious for getting a trapped air pocket some where in it. There is variou methods to burp it.

Alec300SD · #23 08-20-2017, 11:32 PM

Here it is: W123 FSM