602 Coolant Capacity Discrepancy
 

Can you guys help me resolve a coolant capacity discrepancy?

I have a 91 and a 92 300D. Engine is 602.962.

In the FSM section 2080 "Replacing Coolant," it says that for Model 124 Engine 602.96, the total capacity is 9.5 liters.

http://www.w124performance.com/service/w124CD1/Program/Maintenance/My81/2080.pdf

But, in section 20-010 "Draining and Pouring In Coolant" it lists the capacity as 8 liters.

http://www.w124performance.com/service/w124CD1/Program/Engine/602_603/20-010.pdf

It refers, of course, to 602.96, not 602.962. And I noticed that, for 602 with AC and ACC, it says 9.5.

Maybe I'm just reading it wrong....can you guys clear up my confusion?

Thanks.

I can't make sense of it either but do know that when you drain coolant (or engine oil, or transmission fluid) you don't get all of it out. So the "total capacity" is always more than the "drain and refill" amount. Cars with air conditioning often get larger radiators, which may affect capacity and there may be other factors. To be safe, measure the amount that you drain and put that much back in.

On top of that, I have noticed that there are discrepancies in the amounts quoted, depending on which Mercedes manual (owner's, service, engine, etc.) you look in. These may be just plain errors in one or another of the manuals -- over the years I've seen plenty.

The main reason I was trying to make sure I have an accurate number is in the event that I briefly cleanse the system with 100% water. Knowing the correct capacity would be helpful in making sure that, at the end of the process, I have a 50/50 mix of coolant and water.

A 50/50 mix is not critical; anything in the ballpark will do unless you have very unusual operating conditions. When I drain my cooling systems, I add 1 gallon of Mercedes coolant and then add distilled water (usually a little less than 1 gallon) until it's full.

The best you can do is mix coolant before filling. I'm familiar with filling with an amount of coolant, an equal amount of water and hoping the water doesn't overflow :)

Sixto
87 300D