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What r the steps for draining coolant & refiling

I want to change out all the fluids myself. I'm thinking it can't hurt to change out coolant since I don't know how well the previous owner took care of the engine.

Is this a fairly easy project? (Change the oil last weekend. It was a mess doing it in the backyard but not a problem).

What are the steps for draining out coolant & putting in new coolant in a 1998 Detroit Diesel 12. 7 L.

  • Where is/are the drain plugs?
  • Do you need to flush system to get all the old coolant out? If so how?
  • How many gals of coolant are required?
  • Where do you fill at? The coolant tank or the radiator? Both I'm thinking.

Is there anything else I need to be aware of?

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Use the drain plug at the bottom of the bottom rad hose , 2 , 5 gal buckets is enough , and take it to your local oil recycling place .

Take the rad cap off when draining .

Now use tap water and run it thru the system , you can just flush that into the ground,

If you think it needs cleaning fill it with water and about a cup of dishwasher soap , then run the truck up to operating temp till it idles with the thermostats open a while , you may want to put cardboard in front of the rad to help it heat .

Drain all that soapy water out and flush again with fresh water twice, heating it up for at least one of the flushes .

Then refill the rad with new coolant and put the cap on , then fill the top tank to level, run it up to temp again and check your level, carry a spare gal of coolant with you as you may have a bubble in the system somewhere that should sort it self out in a day or two.

When you have the coolant out its a good time to change any hoses that are old .

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Be sure to turn heater controls to highest temp, to allow flushing of the heater cores as well. Don't forget the sleeper heater too. While coolant is out, now is a good time to change thermostat too. To hold your fluids, go by a truck garage and get one of those 55 gallon plastic drums that many fluids come in. Cut it down, to a level that will slide under your truck. Being plastic, you can wipe it out and use it for all fluids (oil; coolant; fuel; etc.) Many places will give the drum to you (Smile, take dozen donuts, cold drink, etc.) Not a good idea to let ANY of these fluids loose into the environment. There will always be traces of your fluid in the flush solution. Very bad for wildlife!!! You might consider changing the heater control valve, while the coolant is out of the system. Doesn't cost much and a whole lot easier than having it go at a unplanned time, when coolant is in system and hot!!! Good time to change sleeper heater hoses too. It's amazing how fast a truck can pump ALL the coolant onto the ground, when a hose lets go!!!:-) Use GOOD clamps too!!

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Mike will be eternally grateful.
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