Coolant recovery tanks

[Scarlett]

Do any of you have coolant recovery/expansion tanks on your DD engines and if so what are the advantages or disadvantages. John

 

[eze2bme]

On my 1979 43DC with DD 6-71N's I have recovery tanks - I like being able to check the levels of the coolant without having to open the engine access floor panels to get to the pressure caps and look. Mine are marked HOT and COLD with appropriate level marks.

 

[racclarkson@gmail.com]

I do, John. One plus is no overflow in the bilge if the HE is overfilled. Another is I have a visual on coolant condition when coolant expands into the tank. I also have a good indicator that all is well when the coolant is sucked backed as the motors cool. In other words, the system reaches an equilibrium and you quantify it visually every time you run the boat.

I always know I have the maximum coolant my systems can take. Since I installed ball valves to quickly and neatly drain the coolant, I can also refill with a pump (with HE cap on) with no overflow; i.e., when the HE is full the recovery tank will start to fill.


The tanks are about a 3/4 to 1 gallon and are all you need for my motors. Looks like I stenciled the tanks on dyslexia day.

 

[Scarlett]

Thanks guys, Robert it looks like a fairly long run on the hose works ok. The hose from the filler cap to the bottle goes in on the bottom, is the top hose just a vent line or where does it go?

 

[racclarkson@gmail.com]

John, I don't think the length is of particular importance as long as the hose is good. Very observant. The hoses at top are the overflows. I used to have them go into a gallon jug in the ER sump, but short enough not to siphon back. Now, they just terminate in the sump. If, in my case, the HE is full and the recovery tanks are empty cold, there is not enough coolant to overflow the system.

 

[Scarlett]

Thanks Robert!!!

 

[Westfield 11]

Did you change radiator caps when you added the coolant recovery bottles?

 

[racclarkson@gmail.com]

Did you change radiator caps when you added the coolant recovery bottles?

I did not.

 

[jim rosenthal]

Now why would you need disposable gloves in an engine room that sanitary? Really, RAC.

 

[racclarkson@gmail.com]

Now why would you need disposable gloves in an engine room that sanitary? Really, RAC.

I don't want to infect the machinery.

 

[Seapig100]

Can you please take some more pictures of this system? I would like to see where they are attached to the radiators please.

 

[SEVEN]

Now why would you need disposable gloves in an engine room that sanitary? Really, RAC.

Good question Jim.

 

[racclarkson@gmail.com]

Can you please take some more pictures of this system? I would like to see where they are attached to the radiators please.

Here you go. #1 HE to recovery tank.



#2 in at recovery tank.



#3 overflow out to bilge

 

[Scarlett]

Just got mine and installed them, you need a 1/4 x 3/8 hose barb screwed into the fitting that used to have the copper tube in it as Roberts photo shows. Make sure if you get one of the units from an auto parts store to buy some better hose, don’t use the hose that comes with it, it is crap. John

 

[racclarkson@gmail.com]

Just got mine and installed them, you need a 1/4 x 3/8 hose barb screwed into the fitting that used to have the copper tube in it as Roberts photo shows. Make sure if you get one of the units from an auto parts store to buy some better hose, don’t use the hose that comes with it, it is crap. John

Very true re hose.

 

[Top Hatt Craig]

I did not.

Hi Robert, just curious as I know you know your stuff, but do the caps you’re using have the second seal in them to allow coolant to be drawn back into the heat exchangers at cool down? Do your reservoir levels go up when warm and down again when cool? I assume they do, so where’d you get your caps? Thanks, Craig

 

[racclarkson@gmail.com]

Hi Robert, just curious as I know you know your stuff, but do the caps you’re using have the second seal in them to allow coolant to be drawn back into the heat exchangers at cool down? Do your reservoir levels go up when warm and down again when cool? I assume they do, so where’d you get your caps? Thanks, Craig

Vented cap, 7PSI from any auto parts store. Hot coolant to the recovery tank, cold coolant back into the HE.

 

[Seapig100]

Thank you for the additional pictures. This should be an easy Saturday morning project.

 

[Dreamboat]

Hi Robert

Where did you get the coolant recovery tanks? Do you have a make and model number?

 

[racclarkson@gmail.com]

Hi Robert

Where did you get the coolant recovery tanks? Do you have a make and model number?

A local auto parts store. Don't have the number, but you should be able to get close with the pics.