41 V12 coolant system questions

[bwanapete]

I'm new to this '41 Continental.  Today was a 25 mile drive, first since my acquisition.  Got home and the car leaked coolant in a puddle 3' diameter on the concrete garage floor but seems not to have leaked on the way into the garage.  Gauge had been about 3/4 to hot.

 

1.  With aluminum heads, what antifreeze to use?

2.  If the leak came from the overflow pipe, as I suspect, does this mean I need a new cap, and if so, I'd need advice on selection.  Since there is also leaked antifreeze on the panel in front of the bottom of the radiator, maybe the overflow pipe is not the source, but there is also a little antifreeze behind the radiator.  The lower hose does not look as new as the upper hoses but I don't think that if it leaked, there would be the mess in front of the radiator.

3.  Maybe it was simply overfilled by the seller.  After it cooled down, I looked and could see liquid about 4 or 5 inches down.  Is that considered full?

 

 

[38ShortopConv.]

Could be close to normal!  But  you need to have good head gaskets w/pumps and hoses to start with and a clean radiator. 
If you start with a full radiator and  give  the motor a good drive 10 miles highway speed and stop it will have lost some fluid even drop some coolant on the spot and find its happy level .
  Mine settles   half way up top outlet holes. On a hot day mine will run 3/4 to hot on temp.  gauge.  I run thermostats and zero pressure cap. Used to run 4 Lb. cap and higher  with  recycle  bottle but  still ended up with same fluid level. I gave up on antifreeze, some of that stuff seems to track  thru all sorts of non gaps,  keep it in the garage when frosty. I use soluble oil, very small amount, 24 to 1? ratio, get right grade? engineers cutting oil, they are not all the same. The block stays clean the aluminum heads and pump bushes love it, no  squealing  bushes. I drain my coolant if Im not using car for several weeks, no weeping gaskets, no rusty water. I  can drive all day and finish up with the same level I started with. 

Edited May 31, 2019 by 38ShortopConv. (see edit history)

[19tom40]

Use a Ethelyn Glycol (Prestone, Zerox Peak are some brands) or a Propylene Glycol (Sierra) are both recommended for your engine. Do not use any of the extended life products, just a green colored antifreeze. Save some money and don't buy the premixed, buy the antifreeze and then buy distilled water at the grocery store. You will need approximately 3 1/3 gallons of anti freeze and the same amount of water to fill your system.

 

Feel around the bottom of the hoses to see if they are leaking.

[bwanapete]

Thanks to both of you.  Today I drove a fair amount, without adding coolant.  The temperature stayed in the middle of the gauge.  Must be it had been overfilled by the seller’s agent.  Also I was not aware that it is not a pressurized system.  I have much to learn. Thanks, both of you.  

 

 

[detroitsoul]

Just curious-does the 41 have a reservoir?  I ran into this while finally getting to drive my 38.  There is no reservoir so the overflow comes out a tube that runs down the side of the radiator.

[bwanapete]

The 41 Continental sounds like it is the same as yoursThe 41 is like yours, a tube running down on theback of the radiator on the left side of the car.