Coolant for 8V-71

[treeplanter]

Info on capacity of coolant and would power cool 50 50 be acceptable 8v-71(1971)

[richard5933]

Not sure on your model specifically, but mine takes 23 gallons if I'm replacing all the coolant from tip to tail. That's for the engine, the heater & defroster loop. Might help for comparison.

Isn't Power Cool Detroit Diesel's own product?

[treeplanter]

Yes power cool is a DD product, I believe your correct on the capacity it just seemed a lot,  I know this amount is not accounting for any still remaining in the system. Thank you!

[richard5933]

When you drain the system, in order to get all the old coolant out, keep in mind that there are drain petcocks at both the main heater core and the defroster core.

When you refill, there is an air bleeder at both of these as well, and if you don't bleed the system properly you can get a huge air pocket in the front of the bus, which can be quite problematic.

If you have a circulation boost pump, the seal is lubricated by the coolant. Important to keep that in mind so you don't run it dry for any amount of time. That happened on mine the first time, due to the huge air pocket up front from not bleeding properly. Seal in the pump failed and had to be replaced, which was a royal PITA.

Follow the manual for the specific steps to get the air bled from your system. Makes it much easier.

[dtcerrato]

On our IL671 that we'd been maintaining since 1979 recently we found that when draining the coolant even following da book with all petcocks & vents open to get coolant removed from the hvac & defroster system - if compressed air is used in moderation (just to create a slight pos. Pressure) we can get an additional almost 4 gallons out of the system. Really surprised us after all those years of coolant changes...

[buswarrior]

If that is am mci/upright engine, take clear note of the bleeder on the crossover pipe.

You start changing coolant, you finish with an engine rebuild...

Follow the book.

Happy coaching!
Buswarrior

[luvrbus]

Power Cool is great stuff but you pay for water with the 50/50 mix the 50/50 is great to carry for topping off,it is costly for refills though ask yourself do I need a 50/50 mix,here in Az a 70/30 mix works for us in Alaska it wouldn't

[chessie4905]

Do you really need Power cool on a 1971 8v-71? Green of good brand along with Nalcool should be fine.

[TomC]

Since the 71 series has dry cylinder liners, using good old Prestone green anti-freeze is enough. Get the concentrated stuff and then buy bottled distilled water and mix it 50/50. Good Luck, TomC

[luvrbus]

Since the 71 series has dry cylinder liners, using good old Prestone green anti-freeze is enough. Get the concentrated stuff and then buy bottled distilled water and mix it 50/50. Good Luck, TomC

Why 50/50 if not needed Detroit has never said a 50/50 mixture is the only way ,Advantage with the Power Cool is no additives,no chemial water filters and a longer life,plus if you catch it on sale from a Detroit dealer like WW Williams it cost about 1/2 of what you pay for the green stuff at box stores 

[dtcerrato]

We run a 30/70 mix - the other way around for Alaska in case we get stuck there for a winter! Been running the extended life Prestone green for 40 years w/o issue at 50/50. Just the last couple years started running heavier concentrate for deeper freeze protection... Was wondering if that would be ok (or nasty) on the coolant O rings between head & block?

[treeplanter]

Thank you everyone!