[Rollingstone]

Hi folks,

When our W126s are left standing for almost a couple of years, does the coolant rest mostly in the radiator? I ask because mine had been standing and not driven for around this amount of time, and when I started her up tonight, the level in the reservoir looked very low.

1) Does it take more than 5 mins. for the plastic coolant reservoir to fill after a prolonged non-use of the car?

2) The driveway of my home is on a slight incline downwards - does this make the reservoir look lower than it actually is?

3) What line should it be at to be correctly and amply filled?

Cheers in advance,
RS

 

[281lxm]

Hi folks,

When our W126s are left standing for almost a couple of years, does the coolant rest mostly in the radiator? I ask because mine had been standing and not driven for around this amount of time, and when I started her up tonight, the level in the reservoir looked very low.

1) Does it take more than 5 mins. for the plastic coolant reservoir to fill after a prolonged non-use of the car?

2) The driveway of my home is on a slight incline downwards - does this make the reservoir look lower than it actually is?

3) What line should it be at to be correctly and amply filled?

Cheers in advance,
RS

Much can depend on how long it takes for the Tstat to open with the heater running. If the car was sitting and not run for two years, I would most likely drain and flush the system, start fresh. Even if you had proper MB coolant, it cannot be good for it to sit stagnant in the engine block or radiator for 24 months. I am no expert, but I did just replace my water pump and all the hoses etc and radiator. When I finally got the water pump off the block I had about 1 gallon of fluid that spashed to the ground (I raised the car in the rear when I did it so it would all fall out). I also think there is some small amount of evaporation that could occur. but in your case, I bet the heater core and the block are holding on to most of your coolant. The level, on level ground should be right even with the center seam of the coolant tank. Once you hit about 85C that Tstat should open up for you and let the fluid flow. When I refilled mine, I had the car raised up almost enough to let the tires off the ground, and I ran the car with the cap off, carefully squeezing the top hose to burp the air out of the system, and kept adding fluid after I got to temp. So I would fill with distilled water until the overlfow is level and run to temp and evaluate. Then I would flush the old and put in new Zerex or MB coolant/distilled water.

 

[Rmac58]

Does the heater core have fluid when its not turned on?

 

[281lxm]

I would logically think that even when you request that heat is shut off, some residual fluid would remain in the heater core. I know there is a pump, and a delay for that reason on shut off, but the inlet and outlet are horizontal I think so at best, it is going to be moist. I use my heater primarily for radiator flush purposes, and maybe for 20 minutes combined per year, and that is to just be sure the pipes stay fresh so I "think" it does, but I am not going to find out lol.

 

[Rmac58]

Yeah, I imagine there will be some in the heater.

 

[MBL87560SEC]

Hi Rollingstone & Rmac58,

Yes the heater core is totally full with coolant even when the engine is shut off and sitting for prolonged periods.

My concern would be coolant loosing its anti corrosion capabilities as the coolant Ph changes.. The only time I have ever had a heater core fail was on my Volvo which sat for two years unattended.. That was a big job to rectify.

Years ago.. i.e. many… we were discussing with our Volvo district service rep the topic of heater core failure.. He said here in the US (at the time) the only place this occurred was hot areas of the country where the heater was never used.. i.e. coolant never flushed through it regularly as is the case here in the new england region where heater usage is a three season affair generally.

Just a thought..

Cheers & good luck, MBL

 

[Rmac58]

^ Thanks for the clarification.